Job strain and risk indicators for cardiovascular disease in young female nurses.

This study examined the possible effects of job demands, decision latitude, and job-related social support on risk indicators for cardiovascular disease (CVD) in 165 female nurses. Job strain was measured with the Job Content Questionnaire; CVD risk was measured with insulin, total cholesterol, triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), fibrinogen, tissue-type plasminogen activator (tPA) antigen, tPA activity, plasminogen activator inhibitor-1 antigen, and blood pressure. Multivariate analysis of covariance and regression analyses revealed no effects of either job strain or social support on these risk indicators. All risk indicators deteriorated with age and body mass index. Oral contraceptive use improved fibrinolytic potential and increased HDL-C but had adverse effects on TG levels. Results suggest that in healthy young women job strain is not associated with an unfavorable metabolic or fibrinolytic risk profile. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Improved SERS Intensity from Silver‐Coated Black Silicon by Tuning Surface Plasmons

An economical method of fabricating large‐area (up to a 100‐mm wafer) silver (Ag)‐coated black silicon (BS) substrates is demonstrated by cryogenic deep reactive ion etching with inductively coupled plasma. This method enables a simple adjustment of the spike structure (e.g., height, width, sidewall slope and density of the spikes) on the silicon substrate, which thus offers the advantages of accurate tuning the density and amplitude of the localized surface plasmons after Ag coating. Using this method, an enhancement factor of 10⁹ is achieved for the probe molecule of rhodamine 6G (around two orders of magnitude higher than previous results based on Ag‐coated BS) in surface‐enhanced Raman scattering (SERS) measurement. The presented results pave the way to make Ag‐coated BS substrates as economic and large‐area platforms for diverse surface plasmon related applications (such as SERS and surface plasmon based biosensors).     

Six years of operation of a fluidised bed reactor for denitrification.

At Himmerfj?rden wastewater treatment plant, a fluidised bed reactor for nitrogen removal has been operated since 1997. Despite its small footprint, the system enables a far-reaching nitrogen removal. The current nitrate reduction in the reactor is 95%. The reduction of total nitrogen at the wastewater treatment plant is 80-90% at normal operation. The concentration of nitrate in the effluent is easily controlled by changing the dose of carbon. As part of a series of full-scale experiments, the plant has, for the last two years, been operated without denitrification for a couple of months during spring/summer, in order to benefit a favourable N/P-ratio in the recipient and to counteract the growth of nitrogen fixing blue-green algae, When resuming the dosage of carbon, full denitrification was re-established in about two weeks. Important factors to take into consideration when operating the fluidised bed reactor are the abrasive characteristics of the carrier material (sand), the increased concentration of suspended solids in the effluent, and the importance of a suitable N/P-ratio in the influent, as lack of phosphorus might cause an uncontrolled microbiological growth.     

The effects of vibration loading on adipose stem cell number,viability and differentiation towards bone-forming cells

Mechanical stimulation is an essential factor affecting the metabolism of bone cells and their precursors. We hypothesized that vibration loading would stimulate differentiation of human adipose stem cells (hASCs) towards bone-forming cells and simultaneously inhibit differentiation towards fat tissue. We developed a vibration-loading device that produces 3g peak acceleration at frequencies of 50 and 100 Hz to cells cultured on well plates. hASCs were cultured using either basal medium (BM), osteogenic medium (OM) or adipogenic medium (AM), and subjected to vibration loading for 3 h d^–1 for 1, 7 and 14 day. Osteogenesis, i.e. differentiation of hASCs towards bone-forming cells, was analysed using markers such as alkaline phosphatase (ALP) activity, collagen production and mineralization. Both 50 and 100 Hz vibration frequencies induced significantly increased ALP activity and collagen production of hASCs compared with the static control at 14 day in OM. A similar trend was detected for mineralization, but the increase was not statistically significant. Furthermore, vibration loading inhibited adipocyte differentiation of hASCs. Vibration did not affect cell number or viability. These findings suggest that osteogenic culture conditions amplify the stimulatory effect of vibration loading on differentiation of hASCs towards bone-forming cells.     

Homogeneous single-label biochemical Ras activation assay using time-resolved luminescence

Mutations of the small GTP-binding protein Ras have been commonly found in tumors, and Ras oncogenes have been established to be involved in the early steps of cancerogenesis. The detection of Ras activity is critical in the determination of the cell signaling events controlling cell growth and differentiation. Therefore, development of improved methods for primary screening of novel potential drugs that target small GTPase or their regulators and their signaling pathways is important. Several assays have been developed for small GTPases studies, but all these methods have limitations for a high-throughput screening (HTS) use. Multiple steps including separation, use of radioactive labels or time-consuming immunoblotting, and a need of large quantities of purified proteins are decreasing the user-friendliness of these methods. Here, we have developed a homogeneous H-Ras activity assay based on a single-label utilizing the homogeneous quenching resonance energy transfer technique (QRET). In the QRET method, the binding of a terbium-labeled GTP (Tb-GTP) to small GTPase protein H-Ras protects the signal of the label from quenching, whereas the signal of the nonbound fraction of Tb-GTP is quenched by a soluble quencher. This enables a rapid determination of the changes in the activity status of Ras. The assay optimization showed that only 60 nM concentration of purified H-Ras protein was needed. The functionality of the assay was proved by detecting the effect of H-Ras guanine nucleotide exchange factor, Son of Sevenless. The signal-to-background ratio up to 7.7 was achieved with an average assay coefficient of variation of 9.1%. The use of a low concentration of purified protein is desirable and the signal-to-background ratio of 3.4 was achieved in the assay at a concentration of 60 nM for H-Ras and SOS proteins. The need of only one labeled molecule and the ability to decrease the quantities of purified proteins used in the experiments are valuable qualities in HTS showing the potential of the QRET method.     

High sensitivity luminescence nanoparticle assay for the detection of protein aggregation

Nanoparticle assay utilizing time-resolved luminescence resonance energy transfer (TR-LRET) was developed for the detection of protein aggregation. This mix-and-measure nanoparticle assay is based on the competitive adsorption of the sample and the acceptor-labeled protein to donor europium(III) polystyrene particles. The protein aggregation was detected with the developed TR-LRET nanoparticle assay, UV240 absorbance and dynamic light scattering (DLS). All methods well equally detected the aggregation and aggregates, whose size ranged from single protein to more than 1000 nm aggregates. The developed method allowed the aggregation detection of the entire size range at more than 10,000 times lower concentration, 30 μg/L, compared to UV240 and DLS. The simple-to-use and sensitive nanoparticle assay with existing microtiter plate luminometric instrumentation can find use as a routine tool for protein aggregation studies in biochemical laboratories and for quality assessment of protein products in industry.     

A method for enabling real-time structural deformation in remote handling control system by utilizing offline simulation results and 3D model morphing

A full scale physical test facility, DTP2 (Divertor Test Platform 2) has been established in Finland for demonstrating and refining the Remote Handling (RH) equipment designs for ITER. The first prototype RH equipment at DTP2 is the Cassette Multifunctional Mover (CMM) equipped with Second Cassette End Effector (SCEE) delivered to DTP2 in October 2008. The purpose is to prove that CMM/SCEE prototype can be used successfully for the 2nd cassette RH operations. At the end of F4E grant “DTP2 test facility operation and upgrade preparation”, the RH operations of the 2nd cassette were successfully demonstrated to the representatives of Fusion For Energy (F4E).Due to its design, the CMM/SCEE robot has relatively large mechanical flexibilities when the robot carries the nine-ton-weighting 2nd Cassette on the 3.6-m long lever. This leads into a poor absolute accuracy and into the situation where the 3D model, which is used in the control system, does not reflect the actual deformed state of the CMM/SCEE robot. To improve the accuracy, the new method has been developed in order to handle the flexibilities within the control system's virtual environment. The effect of the load on the CMM/SCEE has been measured and minimized in the load compensation model, which is implemented in the control system software. The proposed method accounts for the structural deformations of the robot in the control system through the 3D model morphing by utilizing the finite element method (FEM) analysis for morph targets. This resulted in a considerable improvement of the CMM/SCEE absolute accuracy and the adequacy of the 3D model, which is crucially important in the RH applications, where the visual information of the controlled device in the surrounding environment is limited.     

Screening and identification of organophosphorus compounds related to the chemical weapons convention with 1D and 2D NMR spectroscopy

Two-dimensional 1H-31P Fast-HMQC was tested for determination of the presence in low concentrations of organophosphorus compounds related to the Chemical Weapons Convention. This method, based on inverse detection, demonstrated high sensitivity and selectivity. Background signals, such as solvent peaks, are suppressed with good efficiency, and organophosphorus compounds present at a concentration level 1-10 microg/mL can be detected within a few hours. In addition, phosphorus-selective one-dimensional 1H-31P HSQC-TOCSY was applied to produce a complete proton spectrum of selected organophosphorus compound from a sample containing intense background resonances. Application of the methods presented in this paper resulted in considerably improved performance of NMR spectroscopy as a complementary technique for screening as well as identification of chemical warfare agents in environmental samples.     

Novel mutant human fibronectin FIII9-10 domain pair with increased conformational stability and biological activity

The ninth and tenth type III domains (FIII9–10) in thecentral cell binding domain of human fibronectin contain integrinreceptor binding sites, including RGD in FIII10 and a synergysite, PHSRN, in FIII9. The specific amino acids that contributeto cell binding have been identified by the use of wild-typeand mutant fragments of human fibronectin containing the FIII9–10domain pair. At high concentrations FIII9–10 mimics, toa large extent, the biological activity of the full-length fibronectinmolecule. However, FIII9 is conformationally unstable, evenin the context of the FIII9–10 pair. Here we report theconstruction of a series of hybrid mouse–human FIII9–10pairs that confer varying degrees of conformational stabilityto FIII9. The conformational stability of the human FIII9 modulewas increased 2–3-fold by substitution of Leu1408 withPro. We demonstrate that the biological activity of this mutantis enhanced. The resulting FIII9–10 mutant has good solutionproperties and will provide a template into which further mutationscan be incorporated in order to probe the structure–functionrelationship of the cell binding module of fibronectin.     

A DDS Synthesizer with Digital Time Domain Interpolator

A DDS type circuit structure for producing numericallyprogrammable square wave clock signal is presented. The high speed D/Aconverter needed in conventional DDS systems is replaced by an tap delay line time domain interpolator thateffectively increases the sampling rate by a factor of . Thus the circuit can be used up to full clock rate withoutimage filtering. A prototype IC with clock frequency of 30 MHz, 5 bitinterpolator and SFDR of –40 dBc up to 10 MHz and –33 dBcup to 15 MHz has been designed and tested.