Photothermal Conversion Characteristics of Silver Nanoparticle Dispersions

This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.Nanoparticle-based direct absorption system is a recent development, which employs nanoparticles to absorb and convert solar energy directly into thermal energy within the fluid volume. This work reports for the first time the use of plasomic nanoparticles (PNPs) to improve the direct photo-thermal conversion efficiency. Rod-shaped silver nanoparticles are synthesized and used as an example to illustrate the photo-thermal conversion characteristics of PNPs and the effect of particle shape. The result reveals a significant role of particle morphology on the photo-thermal conversion efficiency (PTE). For spherical silver particles, constant specific absorption rate (SAR), ~0.14 kW/g, is observed and the PTE increases nearly linearly with the particle concentration. For rod-shaped silver nanoparticles, much higher SARs (2~5 kW/g) are obtained, and the PTE increases from 43% (pure DI water) to 61% at a low concentration of 0.0028%. It is suggested that the increased specific surface area and the absorption spectrum variation are the two main reasons for the strong heating effect of rod-shaped silver nanoparticles

Appropriateness in the Utilization of Emergency Department Services In Hospital Kota Sharu and Hospital Universiti Sains Malaysia

The prime concern in the inappropriate utilization of emergency departments (FD) is compromised management of patients requiring emergency treatment. Kesan utama penyalahgunaan jabatan kecemasan adalah gangguan terhadap perjalanan perkhidmatan ini kepada pesakit yang benar-benar didalam kecemasan atau tenat. Kajian menunjukkan penggunaan jabatan kecemasan bagi kes-kes bukan kecemasan adalah signifikan dibeberapa negara

Calcium isotope fractionation during microbially induced carbonate mineral precipitation

We report the calcium isotope fractionation during the microbially-induced precipitation of calcium carbonate minerals in pure cultures of the marine sulfate-reducing bacterium Desulfovibrio bizertensis. These data are used to explore how the calcium isotope fractionation factor during microbially-induced carbonate mineral precipitation differs from the better-constrained calcium isotope fractionation factors during biogenic or abiotic carbonate mineral precipitation. Bacterial growth was then modulated with antibiotics, and the evolution of δ44Ca in solution was monitored under different microbial growth rates. The faster the microbial growth rate, the larger the calcium isotope fractionation during carbonate mineral precipitation, ranging from Δ44Ca(s-f) between -1.07‰ and -0.48‰. The reported calcium isotope fractionation can help us understand the link between calcium isotope fractionation and microbial metabolism in carbonate minerals precipitated during sedimentary diagenesis.The work was supported by ERC 307582 StG (CARBONSINK) to AVT and NERC 700 NE/R013519/1 to HJ

Application of hepatitis B virus (HBV) DNA sequence polymorphisms to the study of HBV transmission

Short sequences in hypervariable regions of the hepatitis B virus (HBV) genome can be used to identify different strains, providing a novel approach to the study of HBV transmission. The nucleotide sequence in positions 2551-2650 (1: EcoRI site) was determined for serum HBV DNA from 96 Chinese children living in Hong Kong and from 38 of their parents. HBV DNA was extracted and sequenced after amplification with the polymerase chain reaction, using as primers oligonucleotides corresponding to two conserved sequences. Among 82 unrelated children, 32 HBV DNA variants were present. One sequence was present in 33 children and 31 variants were found among the other 49. Siblings within each of nine families had the same variant; in three families siblings had different variants. Six of the eight fathers and 28 of the 30 mothers had HBV DNA sequences identical to those of their offspring. A total of 34 variants were found among the 134 individuals. The hypothesis of random assortment of sequences in parents and children was rejected (P < .00005). Thus, this new approach proves the occurrence of intrafamilial transmission of HBV among Chinese.published_or_final_versio

Association of the Lumican Gene Functional 3 '-UTR Polymorphism with High Myopia

[[abstract]]PURPOSE. The lumican gene (LUM) encodes a major extracellular component of the fibrous mammalian sclera. Alteration in the expression levels of extracellular matrix components may influence scleral shape, which in turn could affect visual acuity. Single-nucleotide polymorphisms (SNPs) in the LUM gene were determined in an investigation of whether LUM gene polymorphisms correlate with high myopia. METHODS. Sequences spanning all three exons, intron-exon boundaries, and promoter regions were determined in 50 normal individuals. Five SNPs were identified, one of which was found to be a newly identified polymorphism. Genomic DNA was prepared from peripheral blood obtained from 201 patients with high myopia and 86 control subjects. Genotypes of the SNPs -1554 T/C (rs3759223), -628 A/-(rs17018757), -59 CC/-(rs3832846), c. 601 T/C (rs17853500), and the novel SNP c. 1567 C>T were determined by polymerase chain reaction. RESULTS. Of the five SNPs, one showed a significant difference between patients and control subjects (c. 1567 C>T, P = 0.0016). Haplotype analysis revealed a significantly higher presence of polymorphisms in patients with myopia (P < 0.0001). Moreover, the c. 1567 T polymorphism was determined to have lower reporter gene activity than that of c. 1567 C. CONCLUSIONS. These observations suggest that LUM gene polymorphisms contribute to the development of high myopia. (Invest Ophthalmol Vis Sci. 2010; 51: 96-102) DOI: 10.1167/iovs.09-361

Muscarinic acetylcholine receptor 1 gene polymorphisms associated with high myopia

[[abstract]]Purpose: Numerous studies, including those using animal models of myopia development and human clinical trials, have shown that the non-selective muscarinic antagonist atropine is effective in preventing the axial elongation that leads to myopia development. Among all of the muscarinic acetylcholine receptors (mAChRs), mAChR 1 (M1) was the most effective in preventing myopic eye change. Our specific aim in this study was to examine the association between high myopia and polymorphisms within the muscarinic acetylcholine receptors 1 gene (CHRM1). Methods: The participants comprised of a high myopia group (n=194; age range, 17-24 years) having a myopic spherical equivalent greater than 6.5 diopters (D) and a control group (n=109; age range, 17-25 years) having a myopic spherical equivalent less than 0.5 D. Genotyping was performed using an assay-on-demand allelic discrimination assay. Polymerase chain reaction (PCR) was performed using 96 well plates on a thermal cycler. The polymorphisms detected were S1 (CHRM1 rs11823728), S2 (CHRM1 rs544978), S3 (CHRM1 rs2186410), and S4 (CHRM1 rs542269). Results: There was a significant difference in the distribution of S2 and S4 between the high myopia and control groups (p=2.40 x 10(-6) and 2.38 x 10(-8), respectively). The odds ratios of AA genotype of S2 and GG genotype of S4 were both 0.08 (95% confidence interval [CI]: 0.02-0.29 and 0.02-0.36, respectively). Logistic regression test revealed S1, S2, and S4 CHRM1 as all being significant in the development of high myopia. Moreover, the distributions of haplotype 4 (Ht4; C/A/A/A) differed significantly between the two groups (p=3.4 x 10(-5), odds ratio: 0.1, 95% CI: 0.03-0.34). Conclusions: Our results suggest that the S2 and S4 polymorphisms of CHRM1 are associated with susceptibility for developing high myopia. S1, S2, and S4 CHRM1 had a co-operative association with high myopia

Enhanced structural and magnetic ordering of FePt/Mn-oxide bilayers by ion-beam bombardment and annealing

This journal issue contain selected papers of APDSC'10Poster Session - A. Magnetic Recording Technologies: PA-7Structural and magnetic properties of FePt thin films were affected strongly by capped MnO x layers prepared by ion-beam bombardment and post-annealing. As-deposited FePt/MnO x bilayer exhibited a magnetically soft fcc phase, and it turned to an ordered fct FePt phase with large coercivity (∼8 kOe) after annealing at 550°C. Increasing the %O 2/Ar in capped MnO x layer during deposition resulted in smaller ordered FePt grains separated by grain boundaries of MnO x. We found that the superlattice (001) peak is broadened considerably with larger amount of MnO x incorporated into FePt, likely due to the hindered formation of hard phase. Our results indicate that FePt/MnO x films deposited with lower %O 2/Ar, the oxygen atoms may occupy the interstitial positions in the FePt lattice to induce a local strain thus enhancing the FePt ordering. Further increased %O 2/Ar in capped MnO x layer, the excess oxygen atoms act a diffusion barrier effectively to inhibit the FePt grain growth and ordering. © 2011 IEEE.published_or_final_versionThe Asia-Pacific Data Storage Conference (APDSC'10), Hualien, Taiwan, 27-29 October 2010. In IEEE Transactions On Magnetics, 2011, v. 47 n. 3, p. 501-50

Generalized Mittag-Leffler Distributions and Processes for Applications in Astrophysics and Time Series Modeling

Geometric generalized Mittag-Leffler distributions having the Laplace transform $\frac{1}{1+\beta\log(1+t^\alpha)},00$ is introduced and its properties are discussed. Autoregressive processes with Mittag-Leffler and geometric generalized Mittag-Leffler marginal distributions are developed. Haubold and Mathai (2000) derived a closed form representation of the fractional kinetic equation and thermonuclear function in terms of Mittag-Leffler function. Saxena et al (2002, 2004a,b) extended the result and derived the solutions of a number of fractional kinetic equations in terms of generalized Mittag-Leffler functions. These results are useful in explaining various fundamental laws of physics. Here we develop first-order autoregressive time series models and the properties are explored. The results have applications in various areas like astrophysics, space sciences, meteorology, financial modeling and reliability modeling.Comment: 12 pages, LaTe

BMP7 reduces inflammation and oxidative stress in diabetic tubulopathy

Bone morphogenetic protein 7 (BMP7) has been reported to confer renoprotective effects in acute and chronic kidney disease models, but its potential role in Type 2 diabetic nephropathy remains unknown. In cultured human proximal tubular epithelial cells (PTECs), exposure to advanced glycation end-products (AGEs) induced overexpression of intercellular adhesion molecule 1 (ICAM1), monocyte chemoattractant protein 1 (MCP1), interleukin 8 (IL-8) and interleukin 6 (IL-6), involving activation of p44/42 and p38 mitogen-activated protein kinase (MAPK) signalling. BMP7 dose-dependently attenuated AGE-induced up-regulation of ICAM1, MCP1, IL-8 and IL-6 at both mRNA and protein levels. Moreover, BMP7 suppressed AGE-induced p38 and p44/42 MAPK phosphorylation and reactive oxygen species production in PTECs. Compared with vehicle control, uninephrectomized db/db mice treated with BMP7 for 8 weeks had significantly lower urinary albumin-to-creatinine ratio (3549±816.2 μg/mg compared with 8612±2037 μg/mg, P=0.036), blood urea nitrogen (33.26±1.09 mg/dl compared with 37.49±0.89 mg/dl, P=0.006), and renal cortical expression of ICAM1 and MCP1 at both gene and protein levels. In addition, BMP7-treated animals had significantly less severe tubular damage, interstitial inflammatory cell infiltration, renal cortical p38 and p44/42 phosphorylation and lipid peroxidation. Our results demonstrate that BMP7 attenuates tubular pro-inflammatory responses in diabetic kidney disease by suppressing oxidative stress and multiple inflammatory signalling pathways including p38 and p44/42 MAPK. Its potential application as a therapeutic molecule in diabetic nephropathy warrants further investigation.postprin