Magnetoacoustic chemical sensors based on swellable polymer microspheres

The goal of this dissertation was to investigate chemical applications of magnetoacoustic sensors based on swellable polymer microspheres. The magnetoacoustic sensor was used to monitor viscosity of starch solution, water loading, and 2-hydroxyethyl methacrylate polymerization. Poly(vinylbenzyl chloride) (polyVBC) microspheres were prepared by suspension polymerization and then derivatized to introduce dicarboxylate groups onto the polymer backbone. Poly(vinylbenzyl chloride-trichlorophenyl acrylate) (polyVBC-TCPA) microspheres were prepared by dispersion polymerization and then derivatized to introduce amine groups onto the polymer backbone. These derivatized polymer microspheres swell and shrink with changing pH. They were entrapped in a hydrogel membrane and the membrane turbidity was investigated by UV/Vis spectrophotometry. Membrane turbidity increased with pH from 6.0 to 8.0 for entrapped aminated polyVBC-TCPA microspheres, and decreased with pH from 2.0 to 8.0 for entrapped dicarboxylated polyVBC microspheres. The change in turbidity with pH was subject to hysteresis that decreased with increasing water content of the hydrogel membrane. A magnetoelastic ribbon coated with a layer of hydrogel membrane with entrapped aminated polyVBC-TCPA or dicarboxylated polyVBC microspheres was used to monitor pH. A thin layer of polyurethane was pre-coated on the ribbon to prevent it from rusting and increase its adhesion to the pH sensitive membrane. The resonance frequency of the sensor increased as pH changed from 6.0 to 8.0 when aminated polyVBC-TCPA microspheres were used, or decreased as pH changed from 2.0 to 8.0 when dicarboxylated polyVBC microspheres were used. The magnitude of the frequency shift was linearly proportional to the particle concentration in the hydrogel membrane. Poly(vinyl alcohol) (PVA) and HYPAN hydrogels were used to make hydrogel membranes. HYPAN hydrogels are hydrophilic acrylate derivatives. They are good for magnetoacoustic sensors due to their high water content, high mechanical strength, and good adhesion to the polyurethane coated ribbon. The new magnetoacoustic sensors do not require any physical connections to the sensing elements. They are ideally suited for applications where physical connections are undesired or not possible

Homozygosity Mapping on Homozygosity Haplotype Analysis to Detect Recessive Disease-Causing Genes from a Small Number of Unrelated, Outbred Patients

Genes involved in disease that are not common are often difficult to identify; a method that pinpoints them from a small number of unrelated patients will be of great help. In order to establish such a method that detects recessive genes identical-by-descent, we modified homozygosity mapping (HM) so that it is constructed on the basis of homozygosity haplotype (HM on HH) analysis. An analysis using 6 unrelated patients with Siiyama-type α1-antitrypsin deficiency, a disease caused by a founder gene, the correct gene locus was pinpointed from data of any 2 patients (length: 1.2–21.8 centimorgans, median: 1.6 centimorgans). For a test population in which these 6 patients and 54 healthy subjects were scrambled, the approach accurately identified these 6 patients and pinpointed the locus to a 1.4-centimorgan fragment. Analyses using synthetic data revealed that the analysis works well for IBD fragment derived from a most recent common ancestor (MRCA) who existed less than 60 generations ago. The analysis is unsuitable for the genes with a frequency in general population more than 0.1. Thus, HM on HH analysis is a powerful technique, applicable to a small number of patients not known to be related, and will accelerate the identification of disease-causing genes for recessive conditions

A quantitatively-modeled homozygosity mapping algorithm, qHomozygosityMapping, utilizing whole genome single nucleotide polymorphism genotyping data

Homozygosity mapping is a powerful procedure that is capable of detecting recessive disease-causing genes in a few patients from families with a history of inbreeding. We report here a homozygosity mapping algorithm for high-density single nucleotide polymorphism arrays that is able to (i) correct genotyping errors, (ii) search for autozygous segments genome-wide through regions with runs of homozygous SNPs, (iii) check the validity of the inbreeding history, and (iv) calculate the probability of the disease-causing gene being located in the regions identified. The genotyping error correction restored an average of 94.2% of the total length of all regions with run of homozygous SNPs, and 99.9% of the total length of them that were longer than 2 cM. At the end of the analysis, we would know the probability that regions identified contain a disease-causing gene, and we would be able to determine how much effort should be devoted to scrutinizing the regions. We confirmed the power of this algorithm using 6 patients with Siiyama-type α1-antitrypsin deficiency, a rare autosomal recessive disease in Japan. Our procedure will accelerate the identification of disease-causing genes using high-density SNP array data

Online Survival Analysis Software to Assess the Prognostic Value of Biomarkers Using Transcriptomic Data in Non-Small-Cell Lung Cancer

In the last decade, optimized treatment for non-small cell lung cancer had lead to improved prognosis, but the overall survival is still very short. To further understand the molecular basis of the disease we have to identify biomarkers related to survival. Here we present the development of an online tool suitable for the real-time meta-analysis of published lung cancer microarray datasets to identify biomarkers related to survival. We searched the caBIG, GEO and TCGA repositories to identify samples with published gene expression data and survival information. Univariate and multivariate Cox regression analysis, Kaplan-Meier survival plot with hazard ratio and logrank P value are calculated and plotted in R. The complete analysis tool can be accessed online at: www.kmplot.com/lung. All together 1,715 samples of ten independent datasets were integrated into the system. As a demonstration, we used the tool to validate 21 previously published survival associated biomarkers. Of these, survival was best predicted by CDK1 (p<1E-16), CD24 (p<1E-16) and CADM1 (p = 7E-12) in adenocarcinomas and by CCNE1 (p = 2.3E-09) and VEGF (p = 3.3E-10) in all NSCLC patients. Additional genes significantly correlated to survival include RAD51, CDKN2A, OPN, EZH2, ANXA3, ADAM28 and ERCC1. In summary, we established an integrated database and an online tool capable of uni- and multivariate analysis for in silico validation of new biomarker candidates in non-small cell lung cancer

High expression of trimethylated histone H3 at lysine 27 predicts better prognosis in non-small cell lung cancer

Epigenetic parameters such as DNA methylation and histone modifications play pivotal roles in carcinogenesis. Global histone modification patterns have been implicated as possible predictors of cancer recurrence and prognoses in a great variety of tumor entities. Our study was designed to evaluate the association among trimethylated histone H3 at lysine 27 (H3K27me3), clinicopathological variables and outcome in early-stage non-small cell lung cancer (NSCLC). The expression of H3K27me3 and its methyltransferase, enhancer of zeste homolog 2 (EZH2) together with proliferating cell nuclear antigen (PCNA) were evaluated by immunohistochemistry in normal lung tissue (n=5) and resected NSCLC patients (n=42). In addition, the specificity of antibody for H3K27me3 was tested by western blot analysis. The optimal cut-off point of H3K27me3 expression for prognosis was determined by the X-tile program. The prognostic significance was determined by means of Kaplan-Meier survival estimates and log-rank tests. As a result, enhanced trimethylation of H3K27me3 was correlated with longer overall survival (OS) and better prognosis (P<0.05). Moreover, both univariate and multivariate analyses indicated that H3K27me3 level was a significant and independent predictor of better survival (hazard ratio, 0.187; 95% confidence interval, 0.066-0.531, P=0.002). Furthermore, H3K27me3 expression was positively correlated with DNA methylation level at CCGG sites while reversely related to EZH2 expression (P<0.05). In conclusion, H3K27me3 level defines unrecognized subgroups of NSCLC patients with distinct epigenetic phenotype and clinical outcome, and can probably be used as a novel predictor for better prognosis in NSCLC patients

Treasury services outsourcing : case of BOA

A study of the motivations for treasury services outsourcing with a case study on Bank of America (BOA)

Temperature field and dynamic types of shallow groundwater in the northwest inland basin: A case study of the Jiuquan East Basin

Temperature is an inherent property of groundwater.Groundwater temperature field and dynamic characteristics are objective manifestations of groundwater flow system.Based on multi-point, long series and high precision groundwater temperature monitoring data, the characteristics of shallow groundwater temperature distribution and dynamic type of water temperature in Jiuquan East Basin are studied, in order to reveal the relationship between the characteristics of shallow groundwater temperature field and groundwater flow system under the influence of human activities such as groundwater exploitation in northwest inland basin.The results show that the shallow groundwater temperature ranges from 9.33℃ to 20.77℃, and the average water temperature is 13.54℃.From the recharge area to the discharge area, the shallow groundwater temperature increases gradually along the direction of groundwater runoff, and the average groundwater temperature in January is higher than that in July.The comparison of different groundwater flow systems with similar circulation depth shows that the shallow groundwater temperature is negatively correlated with groundwater dynamic conditions.The average groundwater temperature of the water flow system with large surface water recharge and strong hydrodynamic conditions is lower, and that of the water flow system with small recharge and weak hydrodynamic conditions is higher.The temperature dynamics of shallow groundwater are affected by human activities such as natural groundwater circulation and groundwater exploitation.From groundwater recharge area to oasis area in the middle reaches and drainage area in the lower reaches, the temperature dynamic of shallow groundwater can be divided into four basic types, which are river recharge type, water temperature stability type, groundwater exploitation related type and sinusoidal fluctuation type respectively