Building the COllaborative Carbon Column Observing Network (COCCON): Long term stability and ensemble performance of the EM27/SUN Fourier transform spectrometer

Abstract. In a 3.5 year long study, the long term performance of a mobile Bruker EM27/SUN spectrometer, used for greenhouse gases observations, is checked with respect to a co-located reference Bruker IFS 125HR spectrometer, which is part of the Total Carbon Column Observing Network (TCCON). We find that the EM27/SUN is stable on timescales of several years, qualifying it as an useful supplement for the existing TCCON network in remote areas. For achieving consistent performance, such an extension requires careful testing of any spectrometers involved by application of common quality assurance measures. One major aim of the COllaborative Carbon Column Observing Network (COCCON) infrastructure is to provide these services to all EM27/SUN operators. In the framework of COCCON development, the performance of an ensemble of 30 EM27/SUN spectrometers was tested and found to be very uniform, enhanced by the centralized inspection performed at the Karlsruhe Institute of Technology prior to deployment. Taking into account measured instrumental line shape parameters for each spectrometer, the resulting average bias across the ensemble in XCO2 is 0.20 ppm, while it is 0.8 ppb for XCH4. As indicated by the executed long-term study on one device presented here, the remaining empirical calibration factor deduced for each individual instrument can be assumed constant over time. Therefore the application of these empirical factors is expected to further improve the EM27/SUN network conformity beyond the raw residual bias reported above.

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Application of electrochemical methods in the development of models for fuel dissolution and container corrosion under nuclear waste disposal conditions

Canadian Journal of Chemistry ◽

10.1139/v97-188 ◽

1997 ◽

Vol 75 (11) ◽

pp. 1566-1584 ◽

Cited By ~ 7

Author(s):

D.W. Shoesmith ◽

W.H. Hocking ◽

B.M. Ikeda ◽

F. King ◽

J.J. Noël ◽

...

Keyword(s):

Nuclear Fuel ◽

Anodic Dissolution ◽

Nuclear Waste ◽

Chloride Solutions ◽

Long Term Stability ◽

Waste Container ◽

Transport Barriers ◽

Long Term Performance ◽

Term Performance

The permanent disposal of nuclear fuel wastes requires the development of models that can assess the performance of a disposal vault over long periods of time. Models to assess the long-term stability of the nuclear fuel (UO2) and the corrosion performance of the waste container (either copper or titanium) have been based on electrochemical principles. Here we review the chemical/electrochemical performance of fuel and the two candidate container materials, and describe some of the electrochemical studies undertaken either to develop the mechanistic understanding upon which these models are based or to measure the values of parameters required to evaluate long-term performance. These include the following: the anodic dissolution of UO2; the reduction of O2 on various specimens of UO2; the crevice corrosion of various titanium alloys; the impedance characteristics of passive films on Ti alloys; the anodic dissolution of copper in chloride solutions; the reduction of O2 on copper; the effect of various transport barriers on the corrosion of copper; and the prediction of the corrosion potential of copper in aerated chloride solutions. Keywords: uranium dioxide, copper, titanium, nuclear waste, oxygen.

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Long-term stability and reusability of molecularly imprinted polymers

Polymer Chemistry ◽

10.1039/c6py01853j ◽

2017 ◽

Vol 8 (4) ◽

pp. 666-673 ◽

Cited By ~ 79

Author(s):

Jozsef Kupai ◽

Mayamin Razali ◽

Sibel Buyuktiryaki ◽

Rustem Kecili ◽

Gyorgy Szekely

Keyword(s):

Molecularly Imprinted Polymers ◽

Functional Monomer ◽

Molecularly Imprinted ◽

Imprinted Polymers ◽

Adsorption Studies ◽

Term Stability ◽

Long Term Stability ◽

Long Term Performance ◽

Term Performance

The effect of crosslinker, functional monomer and extraction on the long-term performance and degradation of molecularly imprinted polymers was investigated through adsorption studies, NMR, SEM, TGA and BET.

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Sintered Glass Monoliths as New Supports for Affinity Columns

10.20944/preprints202103.0298.v1 ◽

2021 ◽

Author(s):

Marco Wilke ◽

Bettina Röder ◽

Martin Paul ◽

Michael G. Weller

Keyword(s):

Specific Binding ◽

Protein A ◽

Peak Shape ◽

Long Term Stability ◽

Sintered Glass ◽

One Step ◽

Pressure Resistance ◽

Long Term Performance ◽

Term Performance

A novel stationary phase for affinity separations is presented. This material is based on sintered borosilicate glass readily available as semi-finished filter plates with defined porosity and surface area. The material shows fast binding kinetics and excellent long-term stability under real application conditions due to lacking macropores and high mechanical rigidity. The glass surface can be easily modified with standard organosilane chemistry to immobilize selective binders or other molecules used for biointeraction. In this paper, the manufacturing of the columns and their respective column holders by 3D printing is shown in detail. The model system protein A/IgG was chosen as an example to examine the properties of such monolithic columns under realistic application conditions. Several specifications, such as (dynamic) IgG capacity, pressure stability, long-term performance, productivity, non-specific binding, and peak shape, are presented. It could be shown that due to the very high separation speed, 250 mg antibody per hour and column can be collected, which surpasses the productivity of most standard columns of the same size. The total IgG capacity of the shown columns is around 4 mg (5.5 mg/mL), which is sufficient for most tasks in research laboratories. The cycle time of an IgG separation can be less than 1 minute. Due to the glass material's excellent pressure resistance, these columns are compatible with standard HPLC systems. This is usually not the case with standard affinity columns, limited to manual use or application in low-pressure systems. The use of a standard HPLC system also improves the ability for automation, which enables the purification of hundreds of cell supernatants in one day. The sharp peak shape of the elution leads to an enrichment effect, which might increase the concentration of IgG by a factor of 3. The final concentration of IgG can be around 7.5 mg/mL without the need for an additional nanofiltration step. The purity of the IgG was > 95% in one step and nearly 99% with a second polishing run.

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Building the COllaborative Carbon Column Observing Network (COCCON): long-term stability and ensemble performance of the EM27/SUN Fourier transform spectrometer

Atmospheric Measurement Techniques ◽

10.5194/amt-12-1513-2019 ◽

2019 ◽

Vol 12 (3) ◽

pp. 1513-1530 ◽

Cited By ~ 15

Author(s):

Matthias Frey ◽

Mahesh K. Sha ◽

Frank Hase ◽

Matthäus Kiel ◽

Thomas Blumenstock ◽

...

Keyword(s):

Standard Deviation ◽

Total Carbon ◽

Data Sets ◽

Term Study ◽

Data Set ◽

Term Stability ◽

Long Term Stability ◽

Long Term Study ◽

Empirical Calibration

Abstract. In a 3.5-year long study, the long-term performance of a mobile, solar absorption Bruker EM27/SUN spectrometer, used for greenhouse gas observations, is checked with respect to a co-located reference Bruker IFS 125HR spectrometer, which is part of the Total Carbon Column Observing Network (TCCON). We find that the EM27/SUN is stable on timescales of several years; the drift per year between the EM27/SUN and the official TCCON product is 0.02 ppmv for XCO2 and 0.9 ppbv for XCH4, which is within the 1σ precision of the comparison, 0.6 ppmv for XCO2 and 4.3 ppbv for XCH4. The bias between the two data sets is 3.9 ppmv for XCO2 and 13.0 ppbv for XCH4. In order to avoid sensitivity-dependent artifacts, the EM27/SUN is also compared to a truncated IFS 125HR data set derived from full-resolution TCCON interferograms. The drift is 0.02 ppmv for XCO2 and 0.2 ppbv for XCH4 per year, with 1σ precisions of 0.4 ppmv for XCO2 and 1.4 ppbv for XCH4, respectively. The bias between the two data sets is 0.6 ppmv for XCO2 and 0.5 ppbv for XCH4. With the presented long-term stability, the EM27/SUN qualifies as an useful supplement to the existing TCCON network in remote areas. To achieve consistent performance, such an extension requires careful testing of any spectrometers involved by application of common quality assurance measures. One major aim of the COllaborative Carbon Column Observing Network (COCCON) infrastructure is to provide these services to all EM27/SUN operators. In the framework of COCCON development, the performance of an ensemble of 30 EM27/SUN spectrometers was tested and found to be very uniform, enhanced by the centralized inspection performed at the Karlsruhe Institute of Technology prior to deployment. Taking into account measured instrumental line shape parameters for each spectrometer, the resulting average bias across the ensemble with respect to the reference EM27/SUN used in the long-term study in XCO2 is 0.20 ppmv, while it is 0.8 ppbv for XCH4. The average standard deviation of the ensemble is 0.13 ppmv for XCO2 and 0.6 ppbv for XCH4. In addition to the robust metric based on absolute differences, we calculate the standard deviation among the empirical calibration factors. The resulting 2σ uncertainty is 0.6 ppmv for XCO2 and 2.2 ppbv for XCH4. As indicated by the executed long-term study on one device presented here, the remaining empirical calibration factor deduced for each individual instrument can be assumed constant over time. Therefore the application of these empirical factors is expected to further improve the EM27/SUN network conformity beyond the scatter among the empirical calibration factors reported above.

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Influence of Stabilization Techniques Used in the Treatment of Low Back Pain on the Level of Kinesiophobia

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18126393 ◽

2021 ◽

Vol 18 (12) ◽

pp. 6393

Author(s):

Przemysław Filipczyk ◽

Karolina Filipczyk ◽

Edward Saulicz

Keyword(s):

Low Back Pain ◽

Back Pain ◽

Manual Therapy ◽

Analogue Scale ◽

Low Back ◽

Term Study ◽

Long Term Study ◽

Long Term Performance ◽

Term Performance

The aim of this study was to try to compare the effectiveness of manual therapy techniques in combination with stabilization techniques: the so-called Australian method and the Neurac method in relation to pain sensations and the level of kinesiophobia. A total of 69 people were examined, divided into three groups of 23 people each. The Visual Analogue Scale was used to assess the antalgic effect, and the Kinesiophobia Causes Scale questionnaire was used to assess the level of kinesiophobia. Patients improved over four weeks, during which they were assessed three times. The evaluation of the desired parameters was also performed over a 24-week period to assess long-term performance. Stabilization techniques are an effective extension of manual therapy techniques in patients with low back pain. People in the groups additionally improved in terms of stabilization techniques, which are characterized by a lower level of kinesiophobia. Its lowest level was found in the group additionally improved with the Neurac method. In the long-term study, the level of kinesiophobia in this group was still maintained at a reduced level. The use of stabilization techniques involving patients in action may significantly affect the level of kinesiophobia, and thus have a much wider effect than just pain reduction.

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Sintered Glass Monoliths as Supports for Affinity Columns

Separations ◽

10.3390/separations8050056 ◽

2021 ◽

Vol 8 (5) ◽

pp. 56

Author(s):

Marco Wilke ◽

Bettina Röder ◽

Martin Paul ◽

Michael G. Weller

Keyword(s):

Specific Binding ◽

Protein A ◽

Peak Shape ◽

Long Term Stability ◽

Sintered Glass ◽

One Step ◽

Pressure Resistance ◽

Long Term Performance ◽

Term Performance

A novel stationary phase for affinity separations is presented. This material is based on sintered borosilicate glass readily available as semi-finished filter plates with defined porosity and surface area. The material shows fast binding kinetics and excellent long-term stability under real application conditions due to lacking macropores and high mechanical rigidity. The glass surface can be easily modified with standard organosilane chemistry to immobilize selective binders or other molecules used for biointeraction. In this paper, the manufacturing of the columns and their respective column holders by 3D printing is shown in detail. The model system protein A/IgG was chosen as an example to examine the properties of such monolithic columns under realistic application conditions. Several specifications, such as (dynamic) IgG capacity, pressure stability, long-term performance, productivity, non-specific binding, and peak shape, are presented. It could be shown that due to the very high separation speed, 250 mg antibody per hour and column can be collected, which surpasses the productivity of most standard columns of the same size. The total IgG capacity of the shown columns is around 4 mg (5.5 mg/mL), which is sufficient for most tasks in research laboratories. The cycle time of an IgG separation can be less than 1 min. Due to the glass material’s excellent pressure resistance, these columns are compatible with standard HPLC systems. This is usually not the case with standard affinity columns, limited to manual use or application in low-pressure systems. The use of a standard HPLC system also improves the ability for automation, which enables the purification of hundreds of cell supernatants in one day. The sharp peak shape of the elution leads to an enrichment effect, which might increase the concentration of IgG by a factor of 3. The final concentration of IgG can be around 7.5 mg/mL without the need for an additional nanofiltration step. The purity of the IgG was > 95% in one step and nearly 99% with a second polishing run.

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Storage Conditions of Conjugated Reagents Can Impact Results of Immunogenicity Assays

Journal of Immunology Research ◽

10.1155/2016/1485615 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 8

Author(s):

Robert J. Kubiak ◽

Nancy Lee ◽

Yuan Zhu ◽

William R. Franch ◽

Sophia V. Levitskaya ◽

...

Keyword(s):

Storage Conditions ◽

Drug Naïve ◽

Consistent Performance ◽

Storage Buffer ◽

Long Term Performance ◽

Immunogenicity Assays ◽

Term Performance ◽

Phosphate Buffered Saline ◽

Time Evaluation

Consistent performance of anti-drug antibody (ADA) assays through all stages of clinical development is critical for the assessment of immunogenicity and interpretation of PK, PD, safety, and efficacy. The electrochemiluminescent assays commonly employed for ADA measurement use drug conjugated with ruthenium and biotin to bind ADA in samples. Here we report an association between high nonspecific ADA responses in certain drug-naïve individuals and the storage buffer of the conjugated reagents used in a monoclonal antibody ADA assay. Ruthenylated reagents stored in phosphate-buffered saline (PBS) buffer had increased levels of aggregate and produced variable and high baseline responses in some subjects. Reagents stored in a histidine-sucrose buffer (HSB) had lower aggregate levels and produced low sample responses. In contrast to PBS, conjugated reagents formulated in HSB remained low in aggregate content and in sample response variability after 5 freeze/thaw cycles. A reagent monitoring control (RMC) serum was prepared for the real-time evaluation of conjugated reagent quality. Using appropriate buffers for storage of conjugated reagents together with RMCs capable of monitoring of reagent aggregation status can help ensure consistent, long-term performance of ADA methods.

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