bluuebunny/crossref_metadata_2025_split huggingface dataset:
Migration of carbon nanotubes from liquid phase to vapor phase in the refrigerant-based nanofluid pool boiling
Authors: Peng Hao , Ding Guoliang , Hu Haitao 
Published: March 2011

AbstractThe migration characteristics of carbon nanotubes from liquid phase to vapor phase in the refrigerant-based nanofluid pool boiling were investigated experimentally. Four types of carbon nanotubes with the outside diameters from 15 to 80 nm and the lengths from 1.5 to 10 μm were used in the experiments. The refrigerants include R113, R141b and n-pentane. The oil concentration is from 0 to 10 wt.%, the heat flux is from 10 to 100 kW·m-2, and the initial liquid-level height is from 1.3 to 3.4 cm. The experimental results indicate that the migration ratio of carbon nanotube increases with the increase of the outside diameter or the length of carbon nanotube. For the fixed type of carbon nanotube, the migration ratio decreases with the increase of the oil concentration or the heat flux, and increases with the increase of the initial liquid-level height. The migration ratio of carbon nanotube increases with the decrease of dynamic viscosity of refrigerant or the increase of liquid phase density of refrigerant. A model for predicting the migration ratio of carbon nanotubes in the refrigerant-based nanofluid pool boiling is proposed, and the predictions agree with 92% of the experimental data within a deviation of ±20%.
Thermal conductivity and viscosity measurements of ethylene glycol-based Al2O3 nanofluids
Authors: Pastoriza-Gallego María José , Lugo Luis , Legido José Luis , Piñeiro Manuel M 
Published: March 2011

AbstractThe dispersion and stability of nanofluids obtained by dispersing Al2O3 nanoparticles in ethylene glycol have been analyzed at several concentrations up to 25% in mass fraction. The thermal conductivity and viscosity were experimentally determined at temperatures ranging from 283.15 K to 323.15 K using an apparatus based on the hot-wire method and a rotational viscometer, respectively. It has been found that both thermal conductivity and viscosity increase with the concentration of nanoparticles, whereas when the temperature increases the viscosity diminishes and the thermal conductivity rises. Measured enhancements on thermal conductivity (up to 19%) compare well with literature values when available. New viscosity experimental data yield values more than twice larger than the base fluid. The influence of particle size on viscosity has been also studied, finding large differences that must be taken into account for any practical application. These experimental results were compared with some theoretical models, as those of Maxwell-Hamilton and Crosser for thermal conductivity and Krieger and Dougherty for viscosity.
Heterogeneous nanofluids: natural convection heat transfer enhancement
Authors: Oueslati Fakhreddine Segni , Bennacer Rachid 
Published: March 2011

AbstractConvective heat transfer using different nanofluid types is investigated. The domain is differentially heated and nanofluids are treated as heterogeneous mixtures with weak solutal diffusivity and possible Soret separation. Owing to the pronounced Soret effect of these materials in combination with a considerable solutal expansion, the resulting solutal buoyancy forces could be significant and interact with the initial thermal convection. A modified formulation taking into account the thermal conductivity, viscosity versus nanofluids type and concentration and the spatial heterogeneous concentration induced by the Soret effect is presented. The obtained results, by solving numerically the full governing equations, are found to be in good agreement with the developed solution based on the scale analysis approach. The resulting convective flows are found to be dependent on the local particle concentration φ and the corresponding solutal to thermal buoyancy ratio N. The induced nanofluid heterogeneity showed a significant heat transfer modification. The heat transfer in natural convection increases with nanoparticle concentration but remains less than the enhancement previously underlined in forced convection case.
Optimal synthesis and characterization of Ag nanofluids by electrical explosion of wires in liquids
Authors: Ju Park Eun , Won Lee Seung , Bang In Cheol , Park Hyung Wook 
Published: March 2011

AbstractSilver nanoparticles were produced by electrical explosion of wires in liquids with no additive. In this study, we optimized the fabrication method and examined the effects of manufacturing process parameters. Morphology and size of the Ag nanoparticles were determined using transmission electron microscopy and field-emission scanning electron microscopy. Size and zeta potential were analyzed using dynamic light scattering. A response optimization technique showed that optimal conditions were achieved when capacitance was 30 μF, wire length was 38 mm, liquid volume was 500 mL, and the liquid type was deionized water. The average Ag nanoparticle size in water was 118.9 nm and the zeta potential was -42.5 mV. The critical heat flux of the 0.001-vol.% Ag nanofluid was higher than pure water.
Extensive complement-dependent enhancement of HIV-1 by autologous non-neutralising antibodies at early stages of infection
Authors: Willey Suzanne , Aasa-Chapman Marlén MI , O'Farrell Stephen , Pellegrino Pierre , Williams Ian , Weiss Robin A , Neil Stuart JD 
Published: March 2011

AbstractBackgroundNon-neutralising antibodies to the envelope glycoprotein are elicited during acute HIV-1 infection and are abundant throughout the course of disease progression. Although these antibodies appear to have negligible effects on HIV-1 infection when assayed in standard neutralisation assays, they have the potential to exert either inhibitory or enhancing effects through interactions with complement and/or Fc receptors. Here we report that non-neutralising antibodies produced early in response to HIV-1 infection can enhance viral infectivity.ResultsWe investigated this complement-mediated antibody-dependent enhancement (C'-ADE) of early HIV infection by carrying out longitudinal studies with primary viruses and autologous sera derived sequentially from recently infected individuals, using a T cell line naturally expressing the complement receptor 2 (CR2; CD21). The C'-ADE was consistently observed and in some cases achieved infection-enhancing levels of greater than 350-fold, converting a low-level infection to a highly destructive one. C'-ADE activity declined as a neutralising response to the early virus emerged, but later virus isolates that had escaped the neutralising response demonstrated an increased capacity for enhanced infection by autologous antibodies. Moreover, sera with autologous enhancing activity were capable of C'ADE of heterologous viral isolates, suggesting the targeting of conserved epitopes on the envelope glycoprotein. Ectopic expression of CR2 on cell lines expressing HIV-1 receptors was sufficient to render them sensitive to C'ADE.ConclusionsTaken together, these results suggest that non-neutralising antibodies to the HIV-1 envelope that arise during acute infection are not 'passive', but in concert with complement and complement receptors may have consequences for HIV-1 dissemination and pathogenesis.
Disease-specific prospective family study cohorts enriched for familial risk
Authors: Hopper John L 
Published: March 2011

AbstractMost common diseases demonstrate familial aggregation; the ratio of the risk for relatives of affected people to the risk for relatives of unaffected people (the familial risk ratio)) > 1. This implies there are underlying genetic and/or environmental risk factors shared by relatives. The risk gradient across this underlying 'familial risk profile', which can be predicted from family history and measured familial risk factors, is typically strong. Under a multiplicative model, the ratio of the risk for people in the upper 25% of familial risk to the risk for those in the lower 25% (the inter-quartile risk gradient) is an order of magnitude greater than the familial risk ratio. If familial risk ratio = 2 for first-degree relatives, in terms of familial risk profile: (a) people in the upper quartile will be at more than 20 times the risk of those in the lower quartile; and (b) about 90% of disease will occur in people above the median. Historically, therefore, epidemiology has compared cases with controlsdissimilarfor underlying familial risk profile. Were gene-environment and gene-gene interactions to exist, environmental and genetic effects could be stronger for people with increased familial risk profile. Studies in which controls are better matched to cases for familial risk profile might be more informative, especially if both cases and controls are over-sampled for increased familial risk. Prospective family study cohort (ProF-SC) designs involving people across a range of familial risk profile provide such a resource for epidemiological, genetic, behavioural, psycho-social and health utilisation research. The prospective aspect gives credibility to risk estimates. The familial aspect allows family-based designs, matching for unmeasured factors, adjusting for underlying familial risk profile, and enhanced cohort maintenance.
Induction of Cyclooxygenase-2 Expression by Hepatitis B Virus Depends on Demethylation-associated Recruitment of Transcription Factors to the Promoter
Authors: Yue Xin , Yang Fang , Yang Yongbo , Mu Yongxin , Sun Wei , Li Wei , Xu Dongping , Wu Jianguo , Zhu Ying 
Published: March 2011

Abstract

Background
The hepatitis B virus (HBV) is a major etiological factor of inflammation and damage to the liver resulting in hepatocellular carcinoma. Transcription factors play important roles in the disordered gene expression and liver injury caused by HBV. However, the molecular mechanisms behind this observation have not been defined.

Results
In this study, we observed that circulating prostaglandin (PGE) 2 synthesis was increased in patients with chronic hepatitis B infection, and detected elevated cyclooxygenase (COX)-2 expression in HBV- and HBx-expressing liver cells. Likewise, the association of HBx with C/EBPβ contributed to the induction of COX-2. The COX-2 promoter was hypomethylated in HBV-positive cells, and specific demethylation of CpG dinucleotides within each of the two NF-AT sites in the COX-2 promoter resulted in the increased binding affinity of NF-AT to the cognate sites in the promoter, followed by increased COX-2 expression and PGE2 accumulation. The DNA methylatransferase DNMT3B played a key role in the methylation of the COX-2 promoter, and its decreased binding to the promoter was responsible for the regional demethylation of CpG sites, and for the increased binding of transcription factors in HBV-positive cells.

Conclusion
Our results indicate that upregulation of COX-2 by HBV and HBx is mediated by both demethylation events and recruitment of multiple transcription factors binding to the promoter.
Comparative analysis of oncogenic genes revealed unique evolutionary features of field Marek's disease virus prevalent in recent years in China
Authors: Tian Mingxing , Zhao Yang , Lin Yan , Zou Nianli , Liu Cheng , Liu Ping , Cao Sanjie , Wen Xintian , Huang Yong 
Published: March 2011

Abstract

Background
Marek's disease (MD) is an economically important viral disease of chickens caused by Marek's disease virus (MDV), an oncogenic herpesvirus. This disease was well controlled since the widespread use of commercial vaccines, but field MDVs have shown continuous increasing in virulence and acquired the ability to overcome the immune response induced by vaccines. Nowadays, MD continues to be a serious threat to poultry industry, isolation and characterization of MDVs are essential for monitoring changes of viruses and evaluating the effectiveness of existing vaccines.

Results
Between 2008 and 2010, 18 field MDV strains were isolated from vaccinated chicken flocks in Sichuan province, China. Three oncogenic genes including Meq, pp38 and vIL-8 genes of the 18 isolates were amplified and sequenced. Homology analysis showed that the deduced amino acid sequences of these three genes exhibit 95.0-98.8%, 99.3-100% and 97.0-98.5% homology respectively with these of other reference strains published in GenBank. Alignment analysis of the nucleotide and deduced amino acid sequences showed that four amino acid mutations in Meq gene and two amino acid mutations in vIL-8 gene displayed perfect regularity in MDVs circulating in China, which could be considered as features of field MDVs prevalent in recent years in China. In addition, one amino acid mutation in pp38 gene can be considered as a feature of virulent MDVs from USA, and three amino acid mutations in Meq gene were identified and unique in very virulent plus (vv+) MDVs. Phylogenetic analysis based on Meq and vIL-8 protein sequences revealed that field MDVs in China evolved independently. Virulence studies showed that CVI988 could provide efficient protection against the field MDVs epidemic recently in China.

Conclusions
This study and other published data in the GenBank have demonstrated the features of Meq, pp38 and vIL-8 genes of MDVs circulating in recent years in Sichuan, China. Mutations, deletions or insertions were observed in these three genes, and some mutations could be considered as the unique marks of the MDVs circulating presently in China. The paper supplies some valuable information concerning the evolution of MDV which is useful for the vaccine development and control of MD in China.
Efficient co-expression of bicistronic proteins in mesenchymal stem cells by development and optimization of a multifunctional plasmid
Authors: Krause Christopher D , Izotova Lara S , Ren Gwangwen , Yuan Zeng-Rong , Shi Yufang , Chen Chiann-Chyi , Ron Yacov , Pestka Sidney 
Published: March 2011

Abstract
Introduction
Local synthesis of interferon within B16 tumors mediates anti-tumor effects. Based on reports that stem cells are recruited to tumors, and because systemic administration of interferon causes dose-limiting undesirable side effects, we wanted to improve the anti-tumor effects of interferon while simultaneously minimizing its systemic side effects by employing mesenchymal stem cells (MSCs) as tumor-localized ectopic producers of interferon. Many vectors exist to fulfill this purpose, but their transfection efficiency and resulting expression levels vary considerably.

Methods
To follow both the recruitment to tumors and the synthesis of interferon by MSCs, we designed a bicistronic vector system that permits fluorescent visualization of vector-transfected and interferon-producing MSCs. We used Mu-IFNαA cDNA as the first cistron and the cherry fluorescent protein cDNA as the second cistron, whose translation requires the internal ribosome entry sequence (IRES) from the encephalomyocarditis virus 5' untranslated region. Observing inconsistent expression of these cistrons in various vectors and cell lines, especially compared with a control plasmid pmaxGFP, we optimized the expression of this bicistronic message by mutating pcDNA3 to facilitate exchange of the promoter and polyadenylation segments controlling both the gene of interest and the eukaryotic antibiotic resistance gene as well as the eukaryotic antibiotic resistance gene itself, and effectively compare the effects of these exchanges, creating plasmid pc3.5.

Results
Murine MSCs stably and ectopically expressing Mu-IFNαA inhibited the establishment of tumors in homogeneic C57/BL6 mice. Mu-IFNαA expressed from the bicistronic message is fully biologically active, but is expressed at only two-thirds of the level observed from a monocistronic message. Cap-dependent translation is threefold more efficient than IRES-driven translation in 293T, B16, and MSC cell lines. Both efficient expression and good transfection efficiency require strong expression of the gene of interest and a chimeric intron. High doses of Mu-IFNαA within tumors inhibited tumor establishment but may not inhibit tumor growth.

Conclusions
Our modified vector and its derived plasmids will find use in stem cell therapeutics, gene expression, mRNA regulation, and transcription regulation. Local release of Mu-IFNαA within tumors may differently affect tumor establishment and tumor growth.
An Audit of the Quality of Endometrial Cancer Care in a Specialised Unit
Authors: De Parkin , Warraich Q , Fleming DJ , Chew GK , Cruickshank ME 
Published: March 2011

Background Endometrial cancer is the 5th most common female cancer in Scotland and though cure rates are good, 25% of women still die of their disease. Staging has been shown to be poorly performed in Scotland-wide audit and inadequate staging is a predictor of worse outcome. Only 12% of women with endometrial cancer in Scotland are operated upon by a specialist gynaecological oncologist. Aims To determine if the quality of staging information in endometrial cancer is improved in a region where all cases are managed by specialist gynaecological oncologists Methods All 108 women diagnosed and treated with endometrial cancer in Grampian in 2002 and 2003 had a retrospective case note assessment of the completeness of staging information. This was compared to previously published Scottish results. Results Completeness of staging was high. The International Federation of Gynecology and Obstetrics (FIGO) stage was available in 100% of women. Chest X Ray was performed in 85% and peritoneal cytology in 93%. Pelvic lymphadenectomy was performed in 28%. All these results were significantly better than in the Scottish audit. Conclusion Centralisation of women with endometrial cancer results in accurate staging information. However it is not yet known what effect this may have on outcome.
Vitamin D Deficiency in Outpatients: - a Scottish Perspective
Authors: Burleigh E , Potter J 
Published: March 2011

Vitamin D deficiency is common in older people and increases risk of falls, osteoporosis and fracture. This may be reduced with supplements. Recent Scottish guidelines recommend routine use of vitamin D and calcium for all older housebound, sunlight deprived or institutionalised people. Whilst many outpatients will undoubtedly meet these criteria, others who would benefit may not. We have determined the extent of vitamin D deficiency in older outpatients in our geographical area, to clarify further whether those found to be deficient, would receive supplementation under current guidelines Methodology 102 new patient referrals to outpatient clinics and day hospital were questioned over their social circumstances and activity levels, and had serum 25 - Hydroxy Vitamin D (25(OH)D) levels measured in wintertime Results Mean age was 79.6 (SD 7.3), 31.4% were housebound and 51.0% exposed their skin to sunlight. 72.6% had insufficient vitamin D levels [25(OH)D <50 nmol/l], 27.5% of whom levels were frankly deficient [25(OH)D <25 nmol/l]. Deficiency was significantly more common in females (p=0.002), those attending the falls clinic or day hospital (p=0.021), the housebound (p=0.012) or patients who never exposed their skin to sunlight (p=0.007). However, even in those patients who were outdoors frequently or who did expose their skin to the sun, the mean vitamin D levels remained insufficient [mean 25(OH)D = 45.6 (SD 26.2) nmol/l and 47.9 (SD 26.3) nmol/l respectively]. Conclusions The prevalence of vitamin D deficiency is high in older outpatients in this geographical area. These patients may benefit from routine vitamin D and calcium, but currently many would not be targeted in recent Scottish Executive recommendations because they are not housebound and sunlight deprived.
An Unusual Presentation of Metastatic Actinomycosis: A case report
Authors: Cheng Kenneth , Kinninmonth Andrew , Tansey Patrick 
Published: March 2011

We report a case of a 49-year-old man presenting with a history of painful swollen leg, due to a solitary metastatic deposit in the tibia. After investigation, it was found to be secondary to infection with Actinomycosis israelii, which is normally a commensal of the oral and buccal cavity. Actinomycosis israelii is the predominant organism causing infectious disease in humans3 and although soft tissue infections are well documented, osseous involvement is very rare.
Dietary and Social Characteristics of Children with Severe Tooth Decay
Authors: Cameron FL , Weaver LT , Wright CM , Welbury RR 
Published: March 2011

Background and Aims Dental decay remains a major public health problem in Scottish children. The aim of this study was to investigate the relationship between diet, bowel habit, social class, and body mass index (BMI) in children with severe tooth decay. Children and Methods A cross sectional study of 165 children aged 3 -11 years attending Glasgow Dental Hospital for extraction of teeth under dental general anaesthesia (DGA), was undertaken. A structured questionnaire was used to obtain information from each child on diet, bowel habit, and social status of their parents. Fibre and sugar scores were calculated from the frequency of consumption of a range of relevant foods. Results The children (mean age 5.7 (SD1.8) years) had between 1 and 20 decayed, missing or filled primary teeth (dmft) with a mean dmft of 7.9 (SD 3.5). 37% ate a chocolate bar daily, and 29% regularly drank a sugary drink after brushing their teeth. An excess of children were from the most deprived parts of the city and they had the worst decay. Children with the worst decay were also significantly thinner. No relationship was found between tooth decay and bowel habit. Conclusions In this selected group of children with poor dental health, those from deprived families were over-represented and had significantly more decay. Severe dental decay was also associated with underweight.