scholarly journals Norwalk-Like Virus Sequences in Mineral Waters: One-Year Monitoring of Three Brands

2002 ◽  
Vol 68 (4) ◽  
pp. 1925-1931 ◽  
Author(s):  
Christian Beuret ◽  
Dorothe Kohler ◽  
Andreas Baumgartner ◽  
Thomas M. Lüthi
Keyword(s):  
Reverse Transcriptase ◽  
Water Samples ◽  
Room Temperature ◽  
Mineral Water ◽  
Mineral Waters ◽  
Long Term Stability ◽  
Test Sensitivity ◽  
Monitoring Study ◽  
One Year

ABSTRACT In a recent study, RNA with nucleotide sequeces specific for “Norwalk-like viruses” (NLV) was detected in 11 different brands of European mineral waters. To clarify this finding, a 1-year monitoring study was conducted. Samples of three European brands of mineral water without gas were monitored weekly by reverse transcriptase PCR using generic and genogroup-specific oligonucleotides. Additional analyses were performed to investigate a possible correlation between NLV sequence contamination and mineral water lot numbers, the long-term stability (persistence) of NLV sequences in mineral water, and the level of contamination. NLV sequences were detected in 53 of 159 samples analyzed (33%) and belonged entirely to genogroup II. Although all NLV strains identified were closely related, three mineral water brand-specific clusters could be identified for both primer systems by sequencing. Analyses of second samples from lots previously shown to be positive for NLV sequences gave corresponding results in 45 of 53 cases (85%) (within a six-pack). NLV persistence was tested by analyzing 10 positive samples after 6 and 12 months of storage in darkness at room temperature. After 6 months, all samples remained positive; after 12 months, 9 of 10 samples were still positive for NLV sequences. No NLV sequences could be detected by analysis of 0.1-liter aliquots of 53 samples shown to be positive by testing of 1-liter volumes. Based on this fact and a test sensitivity of approximately 10 viral units, levels of contamination in positive mineral water samples were estimated to be in the range of 10 to 100 genomic equivalents per liter.

Water repellent room temperature vulcanized silicone for enhancing the long-term stability of perovskite solar cells

Solar Energy ◽  
2021 ◽  
Vol 218 ◽  
pp. 28-34
Author(s):  
Mahmoud Samadpour ◽  
Mahsa Heydari ◽  
Mahdi Mohammadi ◽  
Parisa Parand ◽  
Nima Taghavinia
Keyword(s):  
Solar Cells ◽  
Room Temperature ◽  
Perovskite Solar Cells ◽  
Water Repellent ◽  
Term Stability ◽  
Long Term Stability

One-year long common view measurements with continuous gravimeters

2021 ◽  
Author(s):  
Franck Pereira Dos Santos ◽  
Pierre Vermeulen ◽  
Sylvain Bonvalot ◽  
Germinal Gabalda ◽  
Nicolas Le Moigne ◽  
...  
Keyword(s):  
Geodetic Network ◽  
Cold Atom ◽  
Superconducting Gravimeter ◽  
Common View ◽  
Long Term Stability ◽  
Earth Gravity ◽  
Measurement Session ◽  
One Year ◽  
Metrological Evaluation

<p>Since a few years, several laboratories, institutes or organizations through the world have acquired marketed quantum absolute gravimeters AQG developed by Muquans. Among their potentialities, these new generations of instruments are expected to complement the existing capabilities of long term monitoring of the Earth gravity field. A metrological evaluation of their performances for long-term measurements is thus a first step.</p><p>The LNE-SYRTE gravimetry laboratory in the suburb of Paris, has been designed to accommodate other gravimeters for metrological comparisons, tests and calibrations. Instruments of different classes operate in this well characterized laboratory: a laboratory-based absolute cold atom gravimeter (CAG) and a relative superconducting gravimeter iGrav. Both instruments allow for continuous measurements, Accuracy is guaranteed by the CAG and long-term stability by the iGrav.</p><p>We there have performed a more than one-year long measurement session with the initial version of the marketed quantum gravimeter AQG (AQG-A01).</p><p>An improved version of this AQG (AQG-B01) designed for outdoor measurement and recently acquired by RESIF (the French Seismologic and Geodetic Network) has been also implemented to close this session with a last month of simultaneous data recording involving all the instruments. Finally, we also performed supplementary accuracy tests, in particular to evaluate the Coriolis bias of the two AQG commercial sensors.</p><p>The talk will briefly present the different instruments to rapidly focus on the performances of the AQGs and results of the comparisons.</p>

Development of a 300°C capable SiC based operational amplifier

2010 ◽  
Vol 2010 (HITEC) ◽  
pp. 000305-000309 ◽  
Author(s):  
Vinayak Tilak ◽  
Cheng-Po Chen ◽  
Peter Losee ◽  
Emad Andarawis ◽  
Zachary Stum
Keyword(s):  
Silicon Carbide ◽  
High Temperature ◽  
Operational Amplifier ◽  
Room Temperature ◽  
Open Loop ◽  
Common Source ◽  
Loop Gain ◽  
Long Term Stability ◽  
Silicon Silicon

Silicon carbide based ICs have the potential to operate at temperatures exceeding that of conventional semiconductors such as silicon. Silicon carbide (SiC) based MOSFETs and ICs were fabricated and measured at room temperature and 300°C. A common source amplifier was fabricated and tested at room temperature and high temperature. The gain at room temperature and high temperature was 7.6 and 6.8 respectively. A SiC MOSFET based operational amplifier was also fabricated and tested at room temperature and 300°C. The small signal open loop gain at 1kHz was 60 dB at room temperature and 57 dB at 300°C. Long term stability testing at 300°C of the MOSFET and common source amplifiers showed very little drift.

scholarly journals One-Year Follow-Up of Spa Treatment in Older Patients with Osteoarthritis: A Prospective, Single Group Study

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Jolanta Zwolińska ◽  
Aneta Weres ◽  
Justyna Wyszyńska
Keyword(s):  
Quality Of Life ◽  
Social Relations ◽  
Mineral Waters ◽  
Spa Therapy ◽  
Spa Treatment ◽  
Short And Long Term ◽  
One Year

Introduction. Few studies evaluated the effects of spa therapy on pain perception and quality of life in older people with osteoarthritis. Therefore, the aim of the study was to evaluate the short- and long-term effects of spa therapy on quality of life and pain in patients aged 60 years and older with osteoarthritis. Materials and Methods. 70 patients with generalized osteoarthritis were enrolled in the study. Spa treatment lasted 3 weeks (15 days of treatment) and was applied during a session lasting 120 to 150 minutes a day. All the patients benefited from kinesiotherapy, physical agent modalities, massage, peloid therapy, hydrotherapy with mineral waters, and crenotherapy. Visual Analogue Scale (VAS) for pain, the Laitinen scale, and WHOQOL-BREF questionnaire were used to assess the condition of the patients. The examinations were performed three times: at the beginning of the spa treatment, after three months, and one year after the first examinations. Results. Statistically significant improvements were observed in pain (VAS) between consecutive assessments (p <.001). Laitinen scale also reported beneficial, statistically significant changes in the level of pain (p <.001). The WHOQOL-BREF questionnaire reported a statistically significant improvement in the domain of social relations in 2-3 and 1-3 periods (p = .025 and p = .011, resp.). A significant improvement was recorded in the domain of environment between 2-3 and 1-3 periods (p <.001). Conclusion. Spa treatment reduced the level of pain in majority of the patients in short- and long-term follow-up and contributed to improving the quality of life in the domain of social relations and environment. To confirm the results of this study, there is a need for a randomized controlled trial comparing spa treatment with usual care in the older population with osteoarthritis. Trial Registration Number. This trial was retrospectively registered on 3 January 2018 with NCT03388801.

Commercialization Conditions and Practices Influence the Microbiological Quality of Mineral Waters

2008 ◽  
Vol 71 (6) ◽  
pp. 1253-1257 ◽  
Author(s):  
SÉRGIO A. P. NUNES FILHO ◽  
ANDERSON S. SANT'ANA ◽  
ADRIANO G. CRUZ
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Water Samples ◽  
Mineral Water ◽  
Microbiological Quality ◽  
Mineral Waters ◽  
Fecal Coliforms ◽  
Street Vendors ◽  
Total Coliforms ◽  
Bottled Mineral Water

The objective of the present study was to determine the microbiological quality of bottled mineral water marketed in commercial establishments and by street vendors and to evaluate the influence of the storage and maintenance conditions on the microbiological quality of the product. Ten samples from the same batches of five different brands of water were analyzed, for a total of 50 samples. Of the five brands analyzed, only one (brand A), when collected in a commercial establishment, complied with the legal Brazilian standards for mineral water with respect to the presence of total coliforms, fecal coliforms, and Pseudomonas aeruginosa. The remaining samples failed to comply with these microbiological standards for at least one of the parameters evaluated. The water samples obtained from street vendors were inferior in microbiological quality to samples from the same batch that were obtained from commercial establishments.

scholarly journals A Room Temperature Gas Sensor Based on Sulfonated SWCNTs for the Detection of NO and NO2

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 1116 ◽  
Author(s):  
Eusebiu Ionete ◽  
Stefan Spiridon ◽  
Bogdan Monea ◽  
Elena Stratulat
Keyword(s):  
Room Temperature ◽  
Gas Sensing ◽  
Electrical Response ◽  
Long Term Stability ◽  
Sensing Applications ◽  
Specific Configuration ◽  
P Type ◽  
Walled Carbon Nanotubes ◽  
Type Response

The electrical response of sulfonated single-walled carbon nanotubes (SWCNTs) to NO and NO2, for gas sensing applications, at room temperature, is reported in this work. A specific configuration based on SWCNT deposition between double pair configuration gold electrodes, supported on a substrate, was considered for the sensing device; employed characterization technique where FTIR and SEM. The experimental results showed a p-type response of the sulfonated SWCNTs, with decrease in resistance, under exposure to NO gas (40–200 ppb) and NO2 (40–200 ppb). Also, the sensor responses to successive exposures at NO2 800 ppb together with investigation of long term stability, at 485 ppb for NO, are reported. The reaction mechanism in case of NO and NO2 detection with sulfonated SWCNTs is presented.

scholarly journals Development and test for long-term stability of a synthetic standard for a quantitative Cryptosporidium parvum LightCycler™ PCR assay

2005 ◽  
Vol 3 (1) ◽  
pp. 15-25 ◽  
Author(s):  
Renata Filkorn-Kaiser ◽  
Konrad Botzenhart ◽  
Albrecht Wiedenmann
Keyword(s):  
Cryptosporidium Parvum ◽  
Surrogate Marker ◽  
Target Sequence ◽  
Positive Trend ◽  
Long Term Stability ◽  
Synthetic Standard ◽  
One Year

A recently described quantitative rapid cycle real time PCR (LightCycler™) assay detects Cryptosporidium parvum after in vitro excystation, which is a surrogate marker for the viability of the organisms. In the original assay the quantification standard is a dilution series of C. parvum oocysts with a microscopically determined excystation rate. The need to keep suspensions of viable oocysts in stock and to continuously monitor their excystation rate, however, renders the assay impracticable for routine application. A synthetic standard was developed to replace the in vivo standard and was calibrated using oocysts with known excystation rates. The standard consists of a 486 bp DNA segment ranging from 229 bp upstream to 79 bp downstream of the actual PCR target site. Aliquots of the standard were frozen and stored at −20 °C and at −70 °C or lyophilised and stored at room temperature in the dark. For a period of one year samples preserved with each of the three methods were restored every four or five weeks. They were amplified in the LightCycler™ and the crossing points (CP) were monitored. No significant trend in the raw CP values could be observed for any of the three storage methods. However, when the methods were compared to each other by calculating the CP ratios (−20 °C/−70 °C; −20 °C/lyophilised; −70 °C/lyophilised) at the 10 monitoring dates, the CP ratios −20 °C/−70 °C and −20 °C/lyophilised showed a highly significant positive trend (p&lt;0.0001) while the CP ratio −70 °C/lyophilised did not differ from the null hypothesis (p=0.53). It can be concluded that the latter two preservation methods are both appropriate, while storage at −20 °C is less advisable. Calculations based on the molecular weight of the standard and on the assumption of an average yield of three sporozoites per oocyst led to the conclusion that the target sequence is probably located on a double copy gene

Lanthanide Refractory Semiconductors Based on the Th3P4 Structure

1987 ◽  
Vol 97 ◽  
Author(s):  
K. A. Gschneidner ◽  
J. F. Nakahara ◽  
B. J. Beaudry ◽  
T. Takeshita ◽  
Ames Laboratory
Keyword(s):  
Electrical Resistivity ◽  
Thermal Properties ◽  
Seebeck Coefficient ◽  
Thermoelectric Properties ◽  
Room Temperature ◽  
Type Structure ◽  
Term Stability ◽  
Long Term Stability ◽  
Phase Relationships

ABSTRACTThe phase relationships and the important structural, electrical and thermal properties of the R3X4-R2X3 (where R = lanthanides and X = S, Se and Te) phases having the Th3P4 -type structure are reviewed. The room temperature electrical resistivity and Seebeck coefficient of these materials are independent of R and only slightly dependent on X, but critically dependent on the X:R ratio. The long term stability of these phases is also reviewed. Although these materials have good thermoelectric properties there are some problems which need to be solved before these phases can be utilized in thermoelectric devices. These problems include long term stability, higher than desirable thermal conductivities, and low electron mobilities.

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