Self-Assembled Monolayers of Symmetrical and Mixed Alkyl Fluoroalkyl Disulfides on Gold. 1. Synthesis of Disulfides and Investigation of Monolayer Properties

The synthesis of a variety of symmetrical bis(alkyl) and bis(fluoroalkyl) disulfides as well as mixed alkyl fluoroalkyl disulfides containing ester or amide groups is described. Self-assembled monolayers of these compounds on gold formed by spontaneous adsorption from solution are studied by contact angle measurements and polarized grazing incidence Fourier transform infrared spectroscopy (FTIR). The contact angles indicate tight packing of the molecules and the incorporation of both alkyl and fluoroalkyl chains in the monolayers. By means of FTIR, the typical tilted orientation of the alkyl chains is confirmed for monolayers derived from symmetrical alkyl disulfides, whereas, in self-assembled monolayers of the symmetrical fluorocarbon and the mixed disulfides, the molecules are oriented much closer to the surface normal direction. The wetting properties and the FTIR spectra of monolayers formed by coadsorption of an n-alkanethiol and a perfluorinated thiol are comparable to those formed by the self-assembly of the corresponding mixed disulfide. There is no indication for phase separation in any of the systems studied at room temperature. The mixed alkyl fluoroalkyl disulfides promise to form suitable monolayers on gold for the investigation of heat-induced phase separation on the gold surface

Technology Enhances Literacy & Numeracy Skills in a Play-Based Preschool Classroom

This research project investigated how technology can improve literacy and numeracy skills in a play-based preschool setting. This study looked at four basic literacy skills and four basic numeracy skills that could be enhanced through the use of the KidsAcademy iPad app. This study used a quantitative approach with a dependent sample t-test to look at how literacy and numeracy scores changed from a pre-test to a post-test. Data was analyzed using an average means between the students that used the technology. Findings suggest that the use of technology in preschool can advance literacy and numeracy skills, thus aiding in meeting early childhood curriculum standards

Cost and Outcome Assessment of a Pharmaceutical Care Service for Cancer Patients treated with Capecitabine

Objective: The present study aimed at evaluating the costs and benefits of a pharmaceutical care (PC) service delivered to cancer patients treated with capecitabine compared to standard care (SC) from a health insurance perspective. Methods: An open, prospective, multi-centred cohort study with a preceding control group was chosen as the study design. Colorectal and breast cancer patients treated with capecitabine were included in the study. For a study period of six months control patients received SC whereas intervention patients received intensified PC. Endpoints among others were direct disease-related outpatient and inpatient costs and quality adjusted life years (QALYs). Utility scores were derived from the EQ-5D questionnaire. A cost-utility analysis was conducted with data from retrospectively matched patient pairs. Matching parameters were tumor entity, therapy setting (neoadjuvant, adjuvant or palliative), therapy regimen at time of inclusion and type of health insurance. Results: Thirty patients were analysed in the control group (CG) and 46 patients in the intervention group (IG). The retrospective finding of matched-pairs yielded eleven patient pairs. Costs for antineoplastic therapy played a dominant role in both patient groups (CG: 59 %, IG: 71 % of total direct costs), followed by costs for inpatient stays (CG: 19 %, IG: 14 % of total direct costs). PC was associated with a gain in mean QALYs compared to SC (0.40, SD: 0.14 versus 0.32, SD: 0.19), at lower mean costs (€ 15606, SD: 13816 versus € 16080, SD: 11308), demonstrating dominance of the PC service. The bootstrapping showed that in 87 % of all replications the PC service was associated with a gain in QALYs. According to the cost-effectiveness acceptability curve the probability that PC was a cost-effective strategy was 43 % at a WTP for an additional QALY of € 0, reaching 62 % probability at a WTP of € 29000 per additional QALY, which is about the implicit NICE cost-effectiveness threshold ratio. Conclusion: In terms of common understanding of cost-effectiveness the PC service was a cost-effective service in the studied patient population. The very small sample size of 22 patients included in the analysis limits the validity of the observed positive result. Further studies with a higher sample size are needed to confirm these findings

Penta­decyl­ammonium methyl sulfate

In the crystal of the title compound, C15H34N+·CH3SO4 −, the cations and anions are joined together via strong N—H⋯O hydrogen bonds into layers parallel to (001)

In search of suitable reference genes for gene expression studies of human renal cell carcinoma by real-time PCR

<p>Abstract</p> <p>Background</p> <p>Housekeeping genes are commonly used as endogenous reference genes for the relative quantification of target genes in gene expression studies. No conclusive systematic study comparing the suitability of different candidate reference genes in clear cell renal cell carcinoma has been published to date. To remedy this situation, 10 housekeeping genes for normalizing purposes of RT-PCR measurements already recommended in various studies were examined with regard to their usefulness as reference genes.</p> <p>Results</p> <p>The expression of the potential reference genes was examined in matched malignant and non-malignant tissue specimens from 25 patients with clear cell renal cell carcinoma. Quality assessment of isolated RNA performed with a 2100 Agilent Bioanalyzer showed a mean RNA integrity number of 8.7 for all samples. The between-run variations related to the crossing points of PCR reactions of a control material ranged from 0.17% to 0.38%. The expression of all genes did not depend on age, sex, and tumour stage. Except the genes TATA box binding protein (<it>TBP</it>) and peptidylprolyl isomerase A (<it>PPIA</it>), all genes showed significant differences in expression between malignant and non-malignant pairs. The expression stability of the candidate reference genes was additionally controlled using the software programs geNorm and NormFinder. <it>TBP </it>and <it>PPIA </it>were validated as suitable reference genes by normalizing the target gene <it>ADAM9 </it>using these two most stably expressed genes in comparison with up- and down-regulated housekeeping genes of the panel.</p> <p>Conclusion</p> <p>Our study demonstrated the suitability of the two housekeeping genes <it>PPIA </it>and <it>TBP </it>as endogenous reference genes when comparing malignant tissue samples with adjacent normal tissue samples from clear cell renal cell carcinoma. Both genes are recommended as reference genes for relative gene quantification in gene profiling studies either as single gene or preferably in combination.</p

Dynamic model and stationary shapes of fluid vesicles

A phase-field model that takes into account the bending energy of fluid vesicles is presented. The Canham-Helfrich model is derived in the sharp-interface limit. A dynamic equation for the phase-field has been solved numerically to find stationary shapes of vesicles with different topologies and the dynamic evolution towards them. The results are in agreement with those found by minimization of the Canham-Helfrich free energy. This fact shows that our phase-field model could be applied to more complex problems of instabilities.Comment: Accepted for publication in EPJE. 9 pages, 7 figure

n-Dodecyl­ammonium bromide monohydrate

In the title compound, C12H28N+·Br−·H2O, the ionic pairs formed by n-dodecyl­ammonium cations and bromide anions are arranged into thick layers; these layers are linked in a nearly perpendicular fashion [the angle between the layers is 85.84 (5)°] by hydrogen-bonding inter­actions involving the water mol­ecules. The methyl­ene part of the alkyl chain in the cation adopts an all-trans conformation. In the crystal structure, mol­ecules are linked by inter­molecular N—H⋯Br, O—H⋯Br and N—H⋯O hydrogen bonds

n-Tridecyl­amine chloride monohydrate

In the title compound, C13H30N+·Cl−·H2O, the C13H27 alkyl chain is in an all-trans conformation. In the crystal, inter­molecular N—H⋯Cl, N—H⋯O and O—H⋯Cl hydrogen bonds connect the components into layers parallel to (010), with the alkyl chains oriented approximately perpendicular to these layers

Bending radius limits of different coated REBCO conductor tapes - an experimental investigation with regard to HTS undulators

Compact FELs require short-period, high-field undulators in combination with compact accelerator structures to produce coherent light up to X-rays. Likewise, for the production of low emittance positron beams for future lepton colliders, like CLIC or FCC-ee, high-field damping wigglers are required. Applying high-temperature superconductors (HTS) in form of coated REBCO tape conductors allows reaching higher magnetic fields and larger operating margins as compared to low-temperature superconductors (LTS) like Nb-Ti or Nb~3~Sn. However, short undulator periods like 13 mm may require bending radii of the conductor smaller than 5 mm which induce significant bending strain on the superconducting layer and may harm its conducting properties. In this contribution, we present our designed bending rig and experimental results for coated REBCO tape conductors from various manufacturers and with different properties. Investigated bending radii reach from 20 mm down to 1 mm and optionally include half of a helical twist. To represent magnet winding procedures, the samples were bent at room temperature and then cooled down to T = 77 K in the bent state to test for potential degradation of the superconducting properties