bluuebunny/crossref_metadata_2025 huggingface dataset:
Interactive effect of biochar size and organic amendments on methane consumption in a tropical vertisol
Authors: Kollah B. , Dubey G. , Parasai P. , Saha J. K. , Gangil S. , Mohanty S. R.
Published: January 2015

Biochar (BC) application to agricultural soil has been proposed as an effective countermeasure to mitigate climate change. A laboratory incubation experiment was carried out to gain insight into the effectiveness ofBCon methane (CH4) consumption in a tropical clayey vertisol. Except for the control treatment,BCof two different sizes (<0.25 or 0.25–2.00 mm) was mixed with vermicompost (VC), poultry manure (PM) or farmyard manure (FYM).BCand organic amendment were added to soil at 10% w/w and 80 kg N/ha, respectively.BCincreasedCH4consumption rate,k, in soil, irrespective of organic amendment type. TheCH4consumption potential of soil was greater with the smaller sizeBC(<0.25 mm). Of the three organic amendments,VCexhibited the highestk(0.105) followed byFYM(0.093) andPM(0.072).BC(<0.25 mm) + PMwas the most effective of the organic amendments in enhancingCH4consumption (k = 0.242). The lag phase varied between 7.3 day (control) and 1.0 day (soil + VC). Results revealed that there was a significant (P < 0.0001) effect of organic amendment andBConCH4consumption,CO2production and microbial abundance. CumulativeCO2production (mg/g soil) varied between 2.15 (control) and 8.77 (soil + PM + BC < 0.25 mm). Pearson's correlation analysis showed significant correlation betweenCH4consumption and methanotrophs abundance (P < 0.001). The study shows thatBCenhancedCH4consumption potential in agricultural land on a tropical vertisol, particularly using the smaller size (<0.25 mm), and could be an effective strategy to mitigate atmosphericCH4.
Characterization of a new HLA allele: HLA‐A*29:49
Authors: Zhai P.‐C. , Zhang Y. , Li Y.‐L. , Zhu C.‐F.
Published: January 2015

The new A*29:49 differs from A*29:01:01:01 by one nucleotide at nt 368.
The novel HLA‐B*39:93 allele was identified by sequence‐based typing in a French family
Authors: Elsermans V. , Top I. , Farchi O. , Varlet P. , Labalette M.
Published: January 2015

A novel HLA‐B allele, B*39:93, was identified in a French family.
Identification of the novel allele, HLA‐B*27:131
Authors: Wang J. , Kostur C. , Stamm L. , Khan F. , Berka N.
Published: January 2015

The novel allele, HLA‐B*27:131, was identified and full genomic DNA was successfully cloned.
FCGR3B gene frequencies among ethnic Thai blood donors from a regional hospital in Eastern Thailand
Authors: Kongmaroeng C. , Kumkaen K.
Published: January 2015

The FCGR3B gene encodes three human neutrophil antigens which consist of HNA‐1a, HNA‐1b, and HNA‐1c. These antigens are encoded by three alleles in the FCGR3B locus: FCGR3B*01, FCGR3B*02, and FCGR3B*03 alleles, respectively. The frequencies of FCGR3B alleles have been reported in different ethnic populations. This study compared the FCGR3B gene frequencies among 230 unrelated healthy Eastern Thai blood donors in Rayong hospital with the previously published studies. The polymerase chain reaction‐sequence‐specific primers method was performed to determine FCGR3B genotypes. The results showed that the allele frequencies of FCGR3B*01, FCGR3B*02, and FCGR3B*03 were 0.722, 0.274, and 0.009, respectively. The FCGR3B*01 and FCGR3B*02 frequencies found in the Eastern Thais were similar to the previous reports investigating in Northern Thais, Chinese Han, Taiwanese, and Japanese populations. Interestingly, our data showed statistically significant difference (P < 0.05) to Central Thais, Korean, Indian, Turkish, Australian, Tunisian, American, German, and Italian populations. In addition, one FCGR3Bnull, which represents a gene deletion, was also found in this study. This information is important not only for the assessment of neutrophil antibody‐mediated clinical conditions and for disease association studies but also for anthropological studies.
Identification of a new non‐synonymous mutation in HLA‐B gene, HLA‐B*15:320, in a Chinese individual by sequence‐based typing
Authors: Dai D. P. , Zhou X. Y. , Cai J. P.
Published: January 2015

The novel allele HLA‐B*15:320 differs from HLA‐B*15:01:01:01 at position 709 in exon 4 (A>T, Ile>Phe).
Polymorphisms of HLA‐A, ‐B, ‐Cw and DRB1 antigens in Moroccan patients with ankylosing spondylitis and a comparison of clinical features with frequencies of HLA‐B*27
Authors: El Mouraghi I. , Ouarour A. , Ghozlani I. , Collantes E. , Solana R. , El Maghraoui A.
Published: January 2015

Ankylosing spondylitis (AS) is very often associated with human leukocyte antigen (HLA), particularly HLA‐B*27. However, the strength of this association and clinical features may vary in different ethnic groups. Our study aims to assess the distribution of HLA‐A, ‐B, ‐Cw and DRB1 alleles in Moroccan patients with AS and to compare the clinical features of AS and the frequencies of HLA‐B27 in patients from Morocco with other series. Seventy‐five patients diagnosed with AS and assessed for clinical manifestations were selected and compared to 100 healthy controls. HLA class I and II antigens were typed by polymerase chain reaction sequence‐specific oligonucleotide. HLA‐B27 subtypes were studied by polymerase chain reaction amplification with sequence‐specific primers. HLA‐B27 was found in 64% of patients. It was positively associated with younger age at disease onset, family history, and uveitis while it had a negative association with late onset. Six B*27 subtypes were identified in the AS group. HLA‐B*2705 and B*2702 were the most common observed subtypes. Among other HLA genes, a significant increase in the prevalence of HLA‐Cw*02 and HLA‐DRB*15 was found in AS patients. HLA‐B27 is involved in the predisposition of AS in the Moroccan population. HLA‐B*2705 and B*2702 were the predominant subtypes supporting previous reports in Caucasian spondyloarthropathies. Other HLA genes, HLA‐Cw*02 and HLA‐DRB1*15, seem to confer predisposing effect to the disease. However, the lower frequency of HLA‐B27 compared to the literature in our study suggests the existence of different genetic and/or environmental factors in Morocco.
B‐cell biomarkers in transplantation – from genes to therapy
Authors: Banham G. D. , Clatworthy M. R.
Published: January 2015

An increased understanding of the mechanisms by which the immune system mounts a response to transplanted organs has allowed the development of immunosuppressive regimens that limit acute T‐cell‐mediated rejection (TCMR). However, the treatment of acute and chronic antibody‐mediated rejection (ABMR) in kidney transplants remains sub‐optimal. The occurrence and severity of antibody‐mediated graft pathology are variable, and genetic polymorphisms that affect the magnitude and nature of the B‐cell response, as well as effector functions of antibody, are likely to contribute to such phenotypic variation. Here we review current efforts to understand and quantify the contribution of B cells to renal transplant pathology by studying variation in DNA, mRNA and proteins. Large genetic studies with information on B‐cell‐specific genetic variants are scarce. At a transcriptomic level, there is evidence that B cells are essential contributors to transplant tolerance and may protect against TCMR and ABMR. In contrast, at the protein level, the detection of donor‐specific human leukocyte antigen (HLA) antibodies and an assessment of their capacity to bind complement allow patients of high immunological risk to be identified. Other biomarkers, such as serum B‐cell‐activating factor (BAFF) or interleukin (IL)‐10‐producing B cells, may allow this risk stratification to be refined. An increased understanding of the significance of these biomarkers should allow a more accurate assessment of how an individual patient's B cells will impact allograft responses and thereby allow clinicians to adjust therapeutic strategies appropriately.
Export Survival in Global Production Chains
Authors: Córcoles David , Díaz‐Mora Carmen , Gandoy Rosario
Published: January 2015

In this paper, we examine the survival capacity of trade relationships in cross‐border production chains. Our main contribution is to show that there are differences in the probability of export interruption between intermediate and final stages along the global value chain, finding a lower sensitivity of intermediate goods to the increasing competition from lower‐income countries. In addition, the paper also makes a methodological contribution by using time‐discrete duration models with product‐country random effects to control for unobservable heterogeneity and by including interactions in the model, in order to identify the sources of these differences. Our estimates show that variables such asEUmembership, export experience, product and market diversification, initial trade value, destination market size, geographical proximity and economic proximity reduce the likelihood of export failure more for intermediate than for final goods, being the differential impact particularly higher for the two first variables. These results would suggest that factors that reduce uncertainty and search costs and increase trust and reliability among production partners are particularly relevant for intermediate stages, fostering the probability of remaining an active member of global production chains.
Experimental and Numerical Investigation of La2NiO4 Membranes for Oxygen Separation: Geometry Optimization and Model Validation
Authors: Habib Mohamed A. , Ahmed Pervez , Ben-Mansour Rached , Mezghani Khaled , Alam Zeeshan , Shao-Horn Y. , Ghoniem A. F.
Published: January 2015

The present work aims at developing a computational model for the prediction of oxygen separation through La2NiO4 disk shaped membranes. The influence of oxygen concentration on the permeation rate was studied experimentally. The model has been validated by comparing the numerical results with those of experiments. The optimal diameter of the inner tube for sweep gas and its distance (gap height) from the membrane surface for maximum oxygen permeation has been investigated. For the present geometry, the optimum gap height (P) is in the range of 0.85–1.25 mm and the optimum diameter (Di) is in the range of 1.5–2.5 mm. Finally it is concluded, as indicated by the numerical and experimental investigations, that with increase in the ratio of O2/N2 mixture on the feed side the oxygen permeation rate increases.
Concurrent Droplet Coalescence and Solidification on Surfaces With Various Wettabilities
Authors: Moghtadernejad Sara , Jadidi Mehdi , Tembely Moussa , Esmail Nabil , Dolatabadi Ali
Published: January 2015

An experimental study is performed to analyze the shear driven droplet shedding on cold substrates with different airflow speeds typical of those in the flight conditions. Understanding the mechanism of simultaneous droplet shedding, coalescence, and solidification is crucial to devise solutions for mitigating aircraft in-flight icing. To mimic this scenario, the experimental setup is designed to generate shear flow as high as 90 m/s. The droplet shedding at high-speed is investigated on a cold surface (0 and −5 °C) of different wettabilities ranging from hydrophilic to superhydrophobic. Result analyses indicate that on a hydrophilic substrate, the droplets form a rivulet, which then freezes on the cold plate. In contrast, on the superhydrophobic surface, there is no rivulet formation. Instead, droplets roll over the substrate and detach from it under the effect of high shear flow.
Investigation on Spray and Flame Lift-Off Length of Acetone–Butanol–Ethanol–Diesel Blend in a Constant Volume Chamber
Authors: Wu Han , Zhang Chunhua , Li Boqi , Lee Timothy H. , Lee Chia-fon F.
Published: January 2015

Acetone–butanol–ethanol (ABE), as the intermediate product during producing biobutanol by fermentation, is considered as a promising alternative fuel due to its advanced properties and lower recovery cost. The spray and combustion process of ABE20 (20% ABE and 80% diesel) and pure diesel was investigated in a constant volume chamber. The tested ambient environments were set at different temperatures (1100 K, 900 K, and 700 K) and oxygen contents (21%, 16%, and 11%) to cover conventional combustion and low temperature combustion (LTC) conditions of diesel engines. The results show that with the addition of 20% ABE, blends exhibit an improved spray characteristics, shorter and narrower spray due to the low viscosity and high volatility of ABE components, and the spray performance impacted much less by environmental condition than that of neat diesel. In addition to the shorter spray penetration, ABE20 also exhibits a much longer flame lift-off length (FLoL) than that of neat diesel, which forms a much bigger gap from spray tip to flame area for ABE20 that will effectively reduce equivalence ratio of combustion region. As a result, the natural flame luminosity which represents the soot emission level of ABE20 is significantly lower than that of pure diesel (D100) at all tested conditions.
Direction-identical scratching method for fabricating nanostructures using a modified AFM nanoscratching system
Authors: Geng Yanquan , Yu Bowen , Yan Yongda , Hu Zhenjiang , Zhao Xuesen
Published: January 2015

To machine nanostructures with consistent depth and quality, a novel direction-identical scratching method based on a modified atomic force microscopy (AFM) probe-based machining system is proposed. During scratching, the optimized scratching direction is precisely maintained by rotating or/and moving the sample mounted on the stage of a modified AFM system. The specific procedures of this scratching method are described in detail and, compared to the conventional method, have the multiple advantages of optimized quality and consistent depth. Also, nanoline and nanochannel patterns are machined using this direction-identical scratching method, which is proved to be highly efficient.
IGF2 is an actionable target that identifies a distinct subpopulation of colorectal cancer patients with marginal response to anti-EGFR therapies
Authors: Zanella Eugenia R. , Galimi Francesco , Sassi Francesco , Migliardi Giorgia , Cottino Francesca , Leto Simonetta M. , Lupo Barbara , Erriquez Jessica , Isella Claudio , Comoglio Paolo M. , Medico Enzo , Tejpar Sabine , Budinská Eva , Trusolino Livio , Bertotti Andrea
Published: January 2015

Colorectal cancers that display reduced sensitivity to EGFR inhibition and strong IGF2 overexpression can be effectively treated by dual EGFR/IGF2 blockade.
Tracking donor-reactive T cells: Evidence for clonal deletion in tolerant kidney transplant patients
Authors: Morris Heather , DeWolf Susan , Robins Harlan , Sprangers Ben , LoCascio Samuel A. , Shonts Brittany A. , Kawai Tatsuo , Wong Waichi , Yang Suxiao , Zuber Julien , Shen Yufeng , Sykes Megan
Published: January 2015

Clonal deletion is a mechanism of graft tolerance after combined kidney and bone marrow transplantation in humans.
MYCing progress against immunosuppression-associated cancers
Authors: Gerber David E.
Published: January 2015

Molecular profiling provides insights into HIV-related lymphoma pathogenesis.
SORTing out lipid handling in atherosclerosis
Authors: Price Elvin
Published: January 2015

Sortilin mediates LDL uptake into macrophages, which contributes to foam cell formation and atherogenesis.
Breaking up is bad for the heart
Authors: White Nathan J.
Published: January 2015

Inhibition of dynamin-related protein 1 prevents cardiac mitochondria from splitting, prevents organ damage, and improves survival after cardiac arrest.
A Hierarchical Cascade of Second Messengers Regulates Pseudomonas aeruginosa Surface Behaviors
Authors: Luo Yun , Zhao Kun , Baker Amy E. , Kuchma Sherry L. , Coggan Kimberly A. , Wolfgang Matthew C. , Wong Gerard C. L. , O’Toole George A.
Published: January 2015

Biofilms are surface-attached multicellular communities. Using single-cell tracking microscopy, we showed that a
pilY1
mutant of
Pseudomonas aeruginosa
is defective in early biofilm formation. We leveraged the observation that PilY1 protein levels increase on a surface to perform a genetic screen to identify mutants altered in surface-grown expression of this protein. Based on our genetic studies, we found that soon after initiating surface growth, cyclic AMP (cAMP) levels increase, dependent on PilJ, a chemoreceptor-like protein of the Pil-Chp complex, and the type IV pilus (TFP). cAMP and its receptor protein Vfr, together with the FimS-AlgR two-component system (TCS), upregulate the expression of PilY1 upon surface growth. FimS and PilJ interact, suggesting a mechanism by which Pil-Chp can regulate FimS function. The subsequent secretion of PilY1 is dependent on the TFP assembly system; thus, PilY1 is not deployed until the pilus is assembled, allowing an ordered signaling cascade. Cell surface-associated PilY1 in turn signals through the TFP alignment complex PilMNOP and the diguanylate cyclase SadC to activate downstream cyclic di-GMP (c-di-GMP) production, thereby repressing swarming motility. Overall, our data support a model whereby P. aeruginosa senses the surface through the Pil-Chp chemotaxis-like complex, TFP, and PilY1 to regulate cAMP and c-di-GMP production, thereby employing a hierarchical regulatory cascade of second messengers to coordinate its program of surface behaviors.

IMPORTANCE
Biofilms are surface-attached multicellular communities. Here, we show that a stepwise regulatory circuit, involving ordered signaling via two different second messengers, is required for
Pseudomonas aeruginosa
to control early events in cell-surface interactions. We propose that our studies have uncovered a multilayered “surface-sensing” system that allows P. aeruginosa to effectively coordinate its surface-associated behaviors
.
Understanding how cells transition into the biofilm state on a surface may provide new approaches to prevent formation of these communities.
Therapeutic guidelines for prescribing antibiotics in neonates should be evidence-based: a French national survey
Authors: Leroux Stéphanie , Zhao Wei , Bétrémieux Pierre , Pladys Patrick , Saliba Elie , Jacqz-Aigrain Evelyne
Published: January 2015

Objective

This survey aims to describe and analyse the dosage regimens of antibiotics in French neonatal intensive care units (NICUs).

Methods

Senior doctors from 56 French NICUs were contacted by telephone and/or email to provide their local guidelines for antibiotic therapy.

Results

44 (79%) NICUs agreed to participate in this survey. In total, 444 dosage regimens were identified in French NICUs for 41 antibiotics. The number of different dosage regimens varied from 1 to 32 per drug (mean 9, SD 7.8). 37% of intravenous dosage regimens used a unique mg/kg dose from preterm to full-term neonates. Doses and/or dosing intervals varied significantly for 12 antibiotics (amikacin, gentamicin, netilmicin, tobramycin, vancomycin administered as continuous infusion, ceftazidime, cloxacillin, oxacillin, penicillin G, imipenem/cilastatin, clindamycin and metronidazole). Among these antibiotics, 6 were used in more than 70% of local guidelines and had significant variations in (1) maintenance daily doses for amikacin, imipenem/cilastatin, ceftazidime and metronidazole; (2) loading doses for continuous infusion of vancomycin; and (3) dosing intervals for gentamicin and amikacin.

Conclusions

A considerable inter-centre variability of dosage regimens of antibiotics exists in French NICUs. Developmental pharmacokinetic–pharmacodynamic studies are essential for the evaluation of antibiotics in order to establish evidence-based dosage regimens for effective and safe administration in neonates.
Prevalence of severe childhood obesity in England: 2006–2013
Authors: Ells Louisa J , Hancock Caroline , Copley Vicky R , Mead Emma , Dinsdale Hywell , Kinra Sanjay , Viner Russell M , Rutter Harry
Published: January 2015

Background

International evidence shows that severe paediatric obesity results in an increased risk of ill health and may require specialised weight management strategies, yet there remains a lack of data on the extent of the problem.

Objective

To examine the prevalence of severe obesity in children aged 4–5 and 10–11 years, attending English schools between 2006/2007 and 2012/2013.

Design

A retrospective analysis of National Child Measurement Programme (NCMP) data.

Setting

Maintained schools in England.

Participants

All children aged 4–5 and 10–11 years included in the NCMP dataset.

Main outcome measures

Prevalence of severe childhood obesity, defined using the 99.6th centile of the British 1990 (UK90) growth reference for body mass index (BMI), analysed by sex, geography, ethnic group and deprivation.

Results

The key findings show that in 2012/2013, severe obesity (BMI ≥UK90 99.6th centile) was found in 1.9% of girls and 2.3% of boys aged 4–5 years, and 2.9% of girls and 3.9% of boys aged 10–11 years. Severe obesity prevalence varies geographically and is more prevalent in children from deprived areas, and among those from black ethnic groups.

Conclusions

The findings from this study should help to raise awareness of the prevalence of severe obesity and support the provision of adequate treatment and prevention services both to support children who are already severely obese and reduce the prevalence of extreme weight in the future.
Non-invasive prenatal testing for sex chromosome abnormalities: a source of confusion
Authors: Kalafat Erkan , Seval Mehmet Murat , Turgay Batuhan , Koç Acar
Published: January 2015

Cell-free fetal DNA has received significant attention for the purposes of prenatal genetic testing in the past decade. Fetal DNA testing is a new method and promising for many applications such as aneuploidy screening, prenatal diagnosis, prediction of preeclampsia and more. A 37-year-old primigravida, with a pregnancy conceived by intracytoplasmic sperm injection (ICSI), was offered non-invasive prenatal testing (NIPT) due to advanced maternal age. NIPT performed at 23 weeks’ gestation reported a diagnosis of monosomy X. She was offered an amniocentesis, which revealed a euploid fetus with no sex chromosome abnormalities. Even with single nucleotide polymorphism-based NIPT, positive predictive value for detection of sex chromosome abnormalities is around 50%. Positive results of NIPT should be heeded with caution and an invasive diagnostic procedure should be performed, especially for rare chromosomal abnormalities and sex chromosome abnormalities where NIPT performs subpar compared to its performance for detection of trisomy 21.
Comparison of Nottingham Prognostic Index and Adjuvant Online prognostic tools in young women with breast cancer: review of a single-institution experience
Authors: Hearne Benjamin Joseph , Teare M Dawn , Butt Mohammad , Donaldson Leslie
Published: January 2015

Objective

Accurately predicting the prognosis of young patients with breast cancer (<40 years) is uncertain since the literature suggests they have a higher mortality and that age is an independent risk factor. In this cohort study we considered two prognostic tools; Nottingham Prognostic Index and Adjuvant Online (Adjuvant!), in a group of young patients, comparing their predicted prognosis with their actual survival.

Setting

North East England

Participants

Data was prospectively collected from the breast unit at a Hospital in Grimsby between January 1998 and December 2007. A cohort of 102 young patients with primary breast cancer was identified and actual survival data was recorded. The Nottingham Prognostic Index and Adjuvant! scores were calculated and used to estimate 10-year survival probabilities. Pearson's correlation coefficient was used to demonstrate the association between the Nottingham Prognostic Index and Adjuvant! scores. A constant yearly hazard rate was assumed to generate 10-year cumulative survival curves using the Nottingham Prognostic Index and Adjuvant! predictions.

Results

Actual 10-year survival for the 92 patients who underwent potentially curative surgery for invasive cancer was 77.2% (CI 68.6% to 85.8%). There was no significant difference between the actual survival and the Nottingham Prognostic Index and Adjuvant! 10-year estimated survival, which was 77.3% (CI 74.4% to 80.2%) and 82.1% (CI 79.1% to 85.1%), respectively. The Nottingham Prognostic Index and Adjuvant! results demonstrated strong correlation and both predicted cumulative survival curves accurately reflected the actual survival in young patients.

Conclusions

The Nottingham Prognostic Index and Adjuvant! are widely used to predict survival in patients with breast cancer. In this study no statistically significant difference was shown between the predicted prognosis and actual survival of a group of young patients with breast cancer.
Trends in antimicrobial resistance in equine bacterial isolates: 1999–2012
Authors: Johns I. C. , Adams E.‐L.
Published: January 2015

This study aimed to identify changing antimicrobial resistance patterns in isolates commonly obtained from equine clinical submissions. Laboratory records from 1999 to 2012 were searched for equine samples from which Escherichia coli or Streptococcus species was isolated. Susceptibility to enrofloxacin, ceftiofur, gentamicin, penicillin G, trimethoprim sulfamethoxazole (TMPS) and tetracyclines was noted. Isolates were divided into those identified between 1999 and 2004 (Early) and between 2007 and 2012 (Late). The proportion of isolates resistant to each antimicrobial and multiple drug‐resistant (MDR) isolates (≥3 antimicrobial classes) was compared between time periods. There were 464 isolates identified (242 Early; 222 Late). A significant increase in the percentage of E coli isolates resistant to ceftiofur (7.3–22.7 per cent, P=0.002), gentamicin (28.5–53.9 per cent, P<0.001), tetracyclines (48.4–74.2 per cent, P=0.002) and MDR (26.6–49.4 per cent, P=0.007) was identified. There was a significant increase over time in the percentage of all streptococcal species resistant to enrofloxacin, ranging from 0 per cent (Early) up to 63 per cent (Late) depending on species. For Streptococcus zooepidemicus, resistance over time to tetracyclines and MDR increased. There was also a decrease in the proportion of S zooepidemicus resistant to TMPS over time. An increase in resistance over time of common equine pathogens to a number of commonly used antimicrobials supports the responsible use of antimicrobials.
Modified Pauli matrix and spin algebra from the Z2-decomposition of the parafermionic Fock space
Authors: Chung Won Sang
Published: January 2015

In this paper the Z2-decomposition of the bosonic Fock space and the projection operators for each subspace are considered. Using these, we obtain two kinds of step operators obeying trilinear relation which resembles the parafermion algebra. The Z2-decomposition of the parafermionic Fock space is also investigated and a new kind of finite-dimensional algebra obeying the trilinear relation which resembles the parafermion algebra of order p. Finally, the modified Pauli matrices and the modified spin algebra are introduced from the Z2-decomposition of the parafermionic Fock space.
Theoretical analysis of terahertz generation in periodically inverted nonlinear crystals based on cascaded difference frequency generation process
Authors: Hu Chen-Fei , Zhong Kai , Mei Jia-Lin , Wang Mao-Rong , Guo Shi-Bei , Xu Wen-Zhong , Liu Peng-Xiang , Xu De-Gang , Wang Yu-Ye , Yao Jian-Quan
Published: January 2015

The characteristics of terahertz (THz) generation based on cascaded difference frequency generation (DFG) process in periodically inverted gallium arsenide ( GaAs ) and gallium phosphide ( GaP ) is calculated from coupled wave equations, in which the output enhancement factors are 5.4 and 3.9 in the two crystals, respectively, compared with DFG without cascading. The optimal interaction length, influence of crystal absorption, wave vector mismatch and pump intensity are analyzed. A short discussion on wavelength tuning is also given. The calculated optimal operating parameters and conclusions can provide good directions for the experimental design.
Dynamic simulation of energy consumption in mixed traffic flow considering highway toll station
Authors: Qian Yong-Sheng , Zhang Xiao-Long , Zeng Jun-Wei , Shao Xiao-Ming , Wang Neng
Published: January 2015

An improved model of energy consumption including toll station is presented in this paper. Using the model, we study the influences of mixed ratio, the idling energy consumption of vehicle, vehicle peak velocity, dwell time and random deceleration probability on energy consumption of Electronic Toll Collection or Manual Toll Collection mixed traffic flow on single lane under periodic condition. Simulating results indicate that the above five parameters are all increasing functions of total energy consumption, in which the idling energy consumption represents the major amounts with the increase of mixed ratio and occupancy rate. Thus, the existence of toll station has significant effect on the energy consumption of mixed traffic flow.
A NEW WAY TO OPTIMIZE DRUG RELEASE RATE OF DRUG ELUTING STENT (DES)
Authors: SUN ANQIANG , WANG ZHENZE , ZHAN FAN , XU ZAIPIN , DENG XIAOYAN
Published: January 2015

Local hemodynamic environment is a determinant factor in drug delivery from a drug eluting stent (DES) to the target arterial tissue. By using a simplified model of a DES, we demonstrated that if a DES had a drug release mode of uniform rate the drug released from the stent will distribute non-uniformly along the stent due to the flowing blood, with a significantly higher drug concentration at the distal part of the stent than that at the proximal one. This may explain why a DES could retard neointimal formation and vascular remodeling in downstream coronary segments. To solve this problem, we thereafter optimized the drug release mode of the DES as an exponential function. The simulation results showed that the optimized drug release mode could lead to a fairly uniform drug concentration distribution along the stent. Therefore, the present study suggested that to achieve a more effective result, optimization of drug eluting strategy (drug release mode) for the DES would be essential.
Exact Safety Verification of Hybrid Systems Based on Bilinear SOS Representation
Authors: Yang Zhengfeng , Lin Wang , Wu Min
Published: January 2015

In this article, we address the problem of safety verification of nonlinear hybrid systems. A hybrid symbolic-numeric method is presented to compute exact inequality invariants of hybrid systems efficiently. Some numerical invariants of a hybrid system can be obtained by solving a bilinear SOS programming via the PENBMI solver or iterative method, then the modified Newton refinement and rational vector recovery techniques are applied to obtain exact polynomial invariants with rational coefficients, which exactly satisfy the conditions of invariants. Experiments on some benchmarks are given to illustrate the efficiency of our algorithm.
On the Discovery of Declarative Control Flows for Artful Processes
Authors: Ciccio Claudio Di , Mecella Massimo
Published: January 2015

Artful processes are those processes in which the experience, intuition, and knowledge of the actors are the key factors in determining the decision making. They are typically carried out by the “knowledge workers,” such as professors, managers, and researchers. They are often scarcely formalized or completely unknown a priori. Throughout this article, we discuss how we addressed the challenge of discovering declarative control flows in the context of artful processes. To this extent, we devised and implemented a two-phase algorithm, named MINERful. The first phase builds a knowledge base, where statistical information extracted from logs is represented. During the second phase, queries are evaluated on that knowledge base, in order to infer the constraints that constitute the discovered process. After outlining the overall approach and offering insight on the adopted process modeling language, we describe in detail our discovery technique. Thereupon, we analyze its performances, both from a theoretical and an experimental perspective. A user-driven evaluation of the quality of results is also reported on the basis of a real case study. Finally, a study on the fitness of discovered models with respect to synthetic and real logs is presented.
GENESIS
Authors: Diamantopoulos Dionysios , Siozios Kostas , Xydis Sotirios , Soudris Dimitrios
Published: January 2015

Placement is though as the most time-consuming processes in physical implementation flows for reconfigurable architectures, while it highly affects the quality of derived application implementation, as it has impact on the maximum operating frequency. Throughout this article, we propose a novel placer, based on genetic algorithm, targeting to FPGAs. Rather than relevant approaches, which are executed sequentially, the new placer exhibits inherent parallelism, which can benefit from multicore processors. Experimental results prove the effectiveness of this solution, as it achieves average reduction of execution runtime and application’s delay by 67× and 16%, respectively.
Interactive Trace-Based Analysis Toolset for Manual Parallelization of C Programs
Authors: Lazarescu Mihai T. , Lavagno Luciano
Published: January 2015

Massive amounts of legacy sequential code need to be parallelized to make better use of modern multiprocessor architectures. Nevertheless, writing parallel programs is still a difficult task. Automated parallelization methods can be effective both at the statement and loop levels and, recently, at the task level, but they are still restricted to specific source code constructs or application domains. We present in this article an innovative toolset that supports developers when performing manual code analysis and parallelization decisions. It automatically collects and represents the program profile and data dependencies in an interactive graphical format that facilitates the analysis and discovery of manual parallelization opportunities. The toolset can be used for arbitrary sequential C programs and parallelization patterns. Also, its program-scope data dependency tracing at runtime can complement the tools based on static code analysis and can also benefit from it at the same time. We also tested the effectiveness of the toolset in terms of time to reach parallelization decisions and of their quality. We measured a significant improvement for several real-world representative applications.
Interval Analysis and Machine Arithmetic
Authors: Gange Graeme , Navas Jorge A. , Schachte Peter , Søndergaard Harald , Stuckey Peter J.
Published: January 2015

The most commonly used integer types have fixed bit-width, making it possible for computations to “wrap around,” and many programs depend on this behaviour. Yet much work to date on program analysis and verification of integer computations treats integers as having infinite precision, and most analyses that do respect fixed width lose precision when overflow is possible. We present a novel integer interval abstract domain that correctly handles wrap-around. The analysis is signedness agnostic. By treating integers as strings of bits, only considering signedness for operations that treat them differently, we produce precise, correct results at a modest cost in execution time.
Community Discovery from Social Media by Low-Rank Matrix Recovery
Authors: Zhuang Jinfeng , Mei Tao , Hoi Steven C. H. , Hua Xian-Sheng , Zhang Yongdong
Published: January 2015

The pervasive usage and reach of social media have attracted a surge of attention in the multimedia research community. Community discovery from social media has therefore become an important yet challenging issue. However, due to the subjective generating process, the explicitly observed communities (e.g., group-user and user-user relationship) are often noisy and incomplete in nature. This paper presents a novel approach to discovering communities from social media, including the group membership and user friend structure, by exploring a low-rank matrix recovery technique. In particular, we take Flickr as one exemplary social media platform. We first model the observed indicator matrix of the Flickr community as a summation of a low-rank
true
matrix and a sparse
error
matrix. We then formulate an optimization problem by regularizing the
true
matrix to coincide with the available rich context and content (i.e., photos and their associated tags). An iterative algorithm is developed to recover the
true
community indicator matrix. The proposed approach leads to a variety of social applications, including community visualization, interest group refinement, friend suggestion, and influential user identification. The evaluations on a large-scale testbed, consisting of 4,919 Flickr users, 1,467 interest groups, and over five million photos, show that our approach opens a new yet effective perspective to solve social network problems with sparse learning technique. Despite being focused on Flickr, our technique can be applied in any other social media community.
Modeling and Analysis of Fault Detection and Fault Tolerance in Wireless Sensor Networks
Authors: Munir Arslan , Antoon Joseph , Gordon-Ross Ann
Published: January 2015

Technological advancements in communications and embedded systems have led to the proliferation of Wireless Sensor Networks (WSNs) in a wide variety of application domains. These application domains include but are not limited to mission-critical (e.g., security, defense, space, satellite) or safety-related (e.g., health care, active volcano monitoring) systems. One commonality across all WSN application domains is the need to meet application requirements (e.g., lifetime, reliability). Many application domains require that sensor nodes be deployed in harsh environments, such as on the ocean floor or in an active volcano, making these nodes more prone to failures. Sensor node failures can be catastrophic for critical or safety-related systems. This article models and analyzes fault detection and fault tolerance in WSNs. To determine the effectiveness and accuracy of fault detection algorithms, we simulate these algorithms using ns-2. We investigate the synergy between fault detection and fault tolerance and use the fault detection algorithms’ accuracies in our modeling of Fault-Tolerant (FT) WSNs. We develop Markov models for characterizing WSN reliability and Mean Time to Failure (MTTF) to facilitate WSN application-specific design. Results obtained from our FT modeling reveal that an FT WSN composed of duplex sensor nodes can result in as high as a 100% MTTF increase and approximately a 350% improvement in reliability over a Non-Fault-Tolerant (NFT) WSN. The article also highlights future research directions for the design and deployment of reliable and trustworthy WSNs.
Joint WCET and Update Activity Minimization for Cyber-Physical Systems
Authors: Huang Yazhi , Zhao Mengying , Xue Chun Jason
Published: January 2015

A cyber-physical system (CPS) is a desirable computing platform for many industrial and scientific applications, such as industrial process monitoring, environmental monitoring, chemical processes, and battlefield surveillance. The application of CPSs has two challenges: First, CPSs often include a number of sensor nodes. Update of preloaded code on remote sensor nodes powered by batteries is extremely energy consuming. The code update issue in the energy-sensitive CPS must be carefully considered. Second, CPSs are often real-time embedded systems with real-time properties. Worst-case execution time (WCET) is one of the most important metrics in real-time system design. Whereas existing works only consider one of these two challenges at a time, in this article, a compiler optimization—joint WCET and update-conscious compilation, or WUCC—is proposed to jointly consider WCET and code update for CPSs. The novelty of the proposed approach is that the WCET problem and code update problem are considered concurrently such that a balanced solution with minimal WCET and minimal code difference can be achieved. The experimental results show that the proposed technique can minimize WCET and code difference effectively.
A Hybrid Task Mapping Algorithm for Heterogeneous MPSoCs
Authors: Quan Wei , Pimentel Andy D.
Published: January 2015

The application workloads in modern MPSoC-based embedded systems are becoming increasingly dynamic. Different applications concurrently execute and contend for resources in such systems, which could cause serious changes in the intensity and nature of the workload demands over time. To cope with the dynamism of application workloads at runtime and improve the efficiency of the underlying system architecture, this article presents a hybrid task mapping algorithm that combines a static mapping exploration and a dynamic mapping optimization to achieve an overall improvement of system efficiency. We evaluate our algorithm using a heterogeneous MPSoC system with three real applications. Experimental results reveal the effectiveness of our proposed algorithm by comparing derived solutions to the ones obtained from several other runtime mapping algorithms. In test cases with three simultaneously active applications, the mapping solutions derived by our approach have average performance improvements ranging from 45.9% to 105.9% and average energy savings ranging from 14.6% to 23.5%.
N
auti
LOD
Authors: Fionda Valeria , Pirrò Giuseppe , Gutierrez Claudio
Published: January 2015

The Web of Linked Data is a huge graph of distributed and interlinked datasources fueled by structured information. This new environment calls for formal languages and tools to automatize navigation across datasources (nodes in such graph) and enable semantic-aware and Web-scale search mechanisms. In this article we introduce a declarative navigational language for the Web of Linked Data graph called N
auti
LOD. N
auti
LOD enables one to specify datasources via the intertwining of navigation and querying capabilities. It also features a mechanism to specify actions (e.g., send notification messages) that obtain their parameters from datasources reached during the navigation. We provide a formalization of the N
auti
LOD semantics, which captures both nodes and fragments of the Web of Linked Data. We present algorithms to implement such semantics and study their computational complexity. We discuss an implementation of the features of N
auti
LOD in a tool called swget, which exploits current Web technologies and protocols. We report on the evaluation of swget and its comparison with related work. Finally, we show the usefulness of capturing Web fragments by providing examples in different knowledge domains.
Raft Refloated
Authors: Howard Heidi , Schwarzkopf Malte , Madhavapeddy Anil , Crowcroft Jon
Published: January 2015

The Paxos algorithm is famously difficult to reason about and even more so to implement, despite having been synonymous with distributed consensus for over a decade. The recently proposed Raft protocol lays claim to being a new, understandable consensus algorithm, improving on Paxos without making compromises in performance or correctness.

In this study, we repeat the Raft authors' performance analysis. We developed a clean-slate implementation of the Raft protocol and built an event-driven simulation framework for prototyping it on experimental topologies. We propose several optimizations to the Raft protocol and demonstrate their effectiveness under contention. Finally, we empirically validate the correctness of the Raft protocol invariants and evaluate Raft's understandability claims.
Locating Arrays
Authors: Aldaco Abraham N. , Colbourn Charles J. , Syrotiuk Violet R.
Published: January 2015

The purpose of a screening experiment is to identify significant factors and interactions on a response for a system. Engineered systems are complex in part due to their size. To apply traditional experimental designs for screening in complex engineered systems requires either restricting the factors considered, which automatically restricts the interactions to those in the set, or restricting interest to main effects, which fails to consider any possible interactions. To address this problem we propose a locating array (LA) as a screening design. Locating arrays exhibit logarithmic growth in the number of factors because their focus is on identification rather than on measurement. This makes practical the consideration of an order of magnitude more factors in experimentation than traditional screening designs. We present preliminary results applying an LA for screening the response of TCP throughput in a simulation model of a mobile wireless network. The full-factorial design for this system is infeasible (over 1043 design points!) yet an LA has only 421 design points. We validate the significance of the identified factors and interactions independently using the statistical software JMP. Screening using locating arrays is viable and yields useful models.
Reconstructable Software Appliances with Kameleon
Authors: Ruiz Cristian , Harrache Salem , Mercier Michael , Richard Olivier
Published: January 2015

A software appliance builder bundles together an application with its needed middleware and an operating system to allow easy deployment on Infrastructure as a Service (IaaS) providers. These builders have the potential to address a key need in our community: the ability to reproduce an experiment. This paper reports the experiences on developing a software appliance builder called Kameleon that leverages popular and well tested tools. Kameleon simplifies the creation of complex software appliances that are targeted at research on operating systems, HPC and distributed computing. It does so by proposing a highly modular description format that encourages collaboration and reuse of procedures. Moreover, it provides debugging mechanisms for improving experimenter's productivity. To justify that our appliance builder stands above others, we compare it with the most known tools used by developers and researchers to automate the construction of software environments for virtual machines and IaaS infrastructures.
A program state machine based virtual processing model in SystemC
Authors: Schmidt Tim , Grüttner Kim , Dömer Rainer , Rettberg Achim
Published: January 2015

The Program State Machine (PSM) Model of Computation offers a rich set of modeling elements to describe behavioral and structural hierarchy, concurrency, synchronization, state transitions and timing. With the rising software complexity of today's embedded systems, the use of Real-Time Operating Systems (RTOS) has become state-of-the-art for nearly all System-on-Chip designs. Regrettably, the PSM model itself has insufficient support for the specification of the preemptive dynamic scheduling behavior of an RTOS. In this paper, we propose a model for dynamically dispatching PSM models on a virtual processing element. Our model aims to abstract from the targeted RTOS and the processor core through execution time annotations and a flexible preemptive scheduler model. Mapping a PSM model to a set of scheduled virtual processing elements only requires minor model transformation and enables early exploration of different processing element mappings and scheduling policies. Our virtual processing model for PSMs is realized on top of the SystemC library. We evaluate the proposed virtual processing model using a Canny edge detection filter.
Specific read only data management for memory hierarchy optimization
Authors: Vaumourin Gregory , Thomas Dombek , Alexandre Guerre , Barthou Denis
Published: January 2015

The multiplication of the number of cores inside embedded systems has raised the pressure on the memory hierarchy. The cost of coherence protocol and the scalability problem of the memory hierarchy is nowadays a major issue. In this paper, a specific data management for read-only data is investigated because these data can be duplicated in several memories without being tracked. Based on analysis of standard benchmarks for embedded systems, this analysis shows that read-only data represent 62% of all the data used by applications and 18% of all the memory accesses. A specific data path for read-only data is then evaluated by using simulations. On the first level of the memory hierarchy, removing read-only data of the L1 cache and placing them in another read-only cache improve the data locality of the read-write data by 30% and decrease the total energy consumption of the first level memory by 5%.