Long-term Properties of Laser Sintered Parts of Polyamide 12 - Influence of Storage Time and Temperature on the Aging Behavior

Whole inshore male capelin (Mallotus villosus) were stored at −23 °C for 2 mo (C2), or 6 mo (C6) prior to thawing, beheading and eviscerating, and refreezing. Though the quality of the twice-frozen product was in both cases inferior to a once-frozen sample, it was still quite acceptable after 2 yr of refrozen storage. As expected, quality was superior in the C2 samples, but in both sets of samples taste deteriorated to a greater extent than texture. Chemical measurement of peroxide value indicated a possible development of rancidity that could not be detected by sensory analysis. Considerable lipid hydrolysis occurred, with the free fatty acids (FFA) at least doubling during storage; increases were greater in C6. In both experiments FFA production correlated with texture, taste, and with extractable protein nitrogen (EPN). Dimethylamine (DMA), trimethylamine (TMA), hypoxanthine, and EPN appeared to be good indicators of storage time and sensory quality. Key words: capelin, dimethylamine (DMA), extractable protein nitrogen (EPN), free fatty acids (FFA), hypoxanthine, peroxide value, refrozen storage, taste, texture, trimethylamine

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Long-term Room Temperature Instability in Thermal Conductivity of InGaZnO Thin Films

MRS Advances ◽

10.1557/adv.2016.142 ◽

2016 ◽

Vol 1 (22) ◽

pp. 1631-1636 ◽

Cited By ~ 2

Author(s):

Boya Cui ◽

D. Bruce Buchholz ◽

Li Zeng ◽

Michael Bedzyk ◽

Robert P. H. Chang ◽

...

Keyword(s):

Thin Films ◽

Thermal Conductivity ◽

Room Temperature ◽

Storage Time ◽

Laser Deposition ◽

Low Oxygen ◽

X Ray Diffraction ◽

3Ω Method ◽

X Ray

ABSTRACTThe cross-plane thermal conductivities of InGaZnO (IGZO) thin films in different morphologies were measured on three occasions within 19 months, using the 3ω method at room temperature 300 K. Amorphous (a-), semi-crystalline (semi-c-) and crystalline (c-) IGZO films were grown by pulsed laser deposition (PLD), followed by X-ray diffraction (XRD) for evaluation of film quality and crystallinity. Semi-c-IGZO shows the highest thermal conductivity, even higher than the most ordered crystal-like phase. After being stored in dry low-oxygen environment for months, a drastic decrease of semi-c-IGZO thermal conductivity was observed, while the thermal conductivity slightly reduced in c-IGZO and remained unchanged in a-IGZO. This change in thermal conductivity with storage time can be attributed to film structural relaxation and vacancy diffusion to grain boundaries.

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3′ MACE RNA-sequencing allows for transcriptome profiling in human tissue samples after long-term storage

Laboratory Investigation ◽

10.1038/s41374-020-0446-z ◽

2020 ◽

Vol 100 (10) ◽

pp. 1345-1355 ◽

Cited By ~ 2

Author(s):

Stefaniya Boneva ◽

Anja Schlecht ◽

Daniel Böhringer ◽

Hans Mittelviefhaus ◽

Thomas Reinhard ◽

...

Keyword(s):

Rna Sequencing ◽

Storage Time ◽

Transcriptome Profiling ◽

Rna Seq ◽

Fresh Tissue ◽

Long Term Storage ◽

Ffpe Samples ◽

The Impact ◽

Term Storage

Abstract This study aims to compare the potential of standard RNA-sequencing (RNA-Seq) and 3′ massive analysis of c-DNA ends (MACE) RNA-sequencing for the analysis of fresh tissue and describes transcriptome profiling of formalin-fixed paraffin-embedded (FFPE) archival human samples by MACE. To compare MACE to standard RNA-Seq on fresh tissue, four healthy conjunctiva from four subjects were collected during vitreoretinal surgery, halved and immediately transferred to RNA lysis buffer without prior fixation and then processed for either standard RNA-Seq or MACE RNA-Seq analysis. To assess the impact of FFPE preparation on MACE, a third part was fixed in formalin and processed for paraffin embedding, and its transcriptional profile was compared with the unfixed specimens analyzed by MACE. To investigate the impact of FFPE storage time on MACE results, 24 FFPE-treated conjunctival samples from 24 patients were analyzed as well. Nineteen thousand six hundred fifty-nine transcribed genes were detected by both MACE and standard RNA-Seq on fresh tissue, while 3251 and 2213 transcripts were identified explicitly by MACE or RNA-Seq, respectively. Standard RNA-Seq tended to yield longer detected transcripts more often than MACE technology despite normalization, indicating that the MACE technology is less susceptible to a length bias. FFPE processing revealed negligible effects on MACE sequencing results. Several quality-control measurements showed that long-term storage in paraffin did not decrease the diversity of MACE libraries. We noted a nonlinear relation between storage time and the number of raw reads with an accelerated decrease within the first 1000 days in paraffin, while the numbers remained relatively stable in older samples. Interestingly, the number of transcribed genes detected was independent on FFPE storage time. RNA of sufficient quality and quantity can be extracted from FFPE samples to obtain comprehensive transcriptome profiling using MACE technology. We thus present MACE as a novel opportunity for utilizing FFPE samples stored in histological archives.

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Long-Term Preservation of Rat Skin Tissue by Epigallocatechin-3-O-Gallate

Cell Transplantation ◽

10.1177/096368970901805-605 ◽

2009 ◽

Vol 18 (5-6) ◽

pp. 513-520 ◽

Cited By ~ 3

Author(s):

Hakhee Kim ◽

Takeshi Kawazoe ◽

Kazuaki Matsumura ◽

Shigehiko Suzuki ◽

Suong-Hyu Hyon

Keyword(s):

Storage Time ◽

Radical Scavenging ◽

Glucose Consumption ◽

Skin Grafts ◽

Dermal Matrix ◽

Skin Sample ◽

Biopsy Specimens ◽

Previously Treated ◽

Long Term Preservation

Skin grafts can be preserved by cryopreservation and refrigerated storage at 4°C. Epigallocatechin-3- O-gallate (EGCG) enhances the viability of stored skin grafts and also extends the storage time up to 7 weeks at 4°C. EGCG, the major polyphenolic constituent present in green tea, has potent antioxidant, antimicrobial, antiproliferative, and free radical scavenging effects. This study examined the effects of EGCG on skin cryopreservation. Skin sample biopsy specimens from GFP rats were previously treated with/without EGCG then moved to −196°C. Skin samples were transplanted to nude mice after 2, 8, and 24 weeks of preservation. Glucose consumption was measured after thawing to assess the metabolic activity. Two weeks later the transplanted skin grafts were excised and histologically analyzed. Histological examinations revealed the degeneration of the epidermal and dermal layers in all groups. In the EGCG groups, the grafts showed higher integrity in the epidermal layer and dermal matrix. The present findings suggest the future clinical usefulness of EGCG for skin preservation; however, the mechanism by which EGCG promotes skin preservation still remains unclear.

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Effects of Long-Term Storage Time and Original Sampling Month on Biobank Plasma Protein Concentrations

EBioMedicine ◽

10.1016/j.ebiom.2016.08.038 ◽

2016 ◽

Vol 12 ◽

pp. 309-314 ◽

Cited By ~ 29

Author(s):

Stefan Enroth ◽

Göran Hallmans ◽

Kjell Grankvist ◽

Ulf Gyllensten

Keyword(s):

Plasma Protein ◽

Storage Time ◽

Long Term Storage ◽

Term Storage

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Fertility of long-term-stored boar semen: Influence of extender (Androhep and Kiev), storage time and plasma droplets in the semen

Animal Reproduction Science ◽

10.1016/0378-4320(94)90061-2 ◽

1994 ◽

Vol 36 (1-2) ◽

pp. 145-151 ◽

Cited By ~ 59

Author(s):

D. Waberski ◽

S. Meding ◽

G. Dirksen ◽

K.F. Weitze ◽

C. Leiding ◽

...

Keyword(s):

Storage Time ◽

Boar Semen

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Comparison of long-term properties of laser sintered and injection molded polyamide 12 parts

Journal of Polymer Engineering ◽

10.1515/polyeng-2017-0227 ◽

2018 ◽

Vol 38 (6) ◽

pp. 573-582 ◽

Cited By ~ 3

Author(s):

Andreas Wörz ◽

Katrin Wudy ◽

Dietmar Drummer ◽

Andreas Wegner ◽

Gerd Witt

Keyword(s):

Degradation Mechanism ◽

Selective Laser Sintering ◽

Small Scale ◽

Scale Production ◽

Direct Transfer ◽

Degradation Behavior ◽

Polyamide 12 ◽

Characteristic Values ◽

Injection Molded

Abstract Selective laser sintering (SLS) of polymers is on the edge from a pure prototyping technique to a small-scale production. For this transition, characteristic values such as long-term properties, and thus the degradation mechanism, are crucial factors for enabling a series application. Due to the specific characteristics of SLS parts like porosity and rough surfaces, a direct transfer of known mechanisms and models for injection molded (IM) parts is not or just to a limited extent possible. This leads to the aim of this paper, which is to investigate and compare the degradation behavior of polyamide 12 parts produced by SLS and IM.

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Stability of Folate and Vitamin B12in Human Serum after Long-Term Storage: A Follow-Up after 13 Years

Journal of Nutrition and Metabolism ◽

10.1155/2018/9834181 ◽

2018 ◽

Vol 2018 ◽

pp. 1-4 ◽

Cited By ~ 5

Author(s):

Eugène H. J. M. Jansen ◽

Piet K. Beekhof

Keyword(s):

Human Serum ◽

Storage Time ◽

Vitamin B ◽

Serum Samples ◽

Long Term Storage ◽

Nutrition Research ◽

The Stability ◽

Term Storage

In epidemiological and nutrition research, it is very important to evaluate the stability of biomarkers as function of both storage time and temperature. In this study, the stability of folate and vitamin B12in human serum samples has been tested after long-term storage at −80°C up to 13 years. Serum samples of 16 individuals were used in this study. The concentration of folate and vitamin B12has been determined att=0and at 1, 8, and 13 years after storage at −80°C. The folate concentrations in serum samples remained stable at −80°C. The concentration of vitamin B12was decreasing during the time of the study to about 50%. The correlation of the folate and also of the vitamin B12concentrations in the stored samples compared with the starting values was still good. Therefore, although the concentration of vitamin B12decreased upon storage, reliable comparative analyses can still be performed.

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Long-Term Isothermal Aging Behavior of V-Modified 2.25Cr-1Mo Steels

Storage Tank Integrity and Materials Evaluation ◽

10.1115/pvp2004-3067 ◽

2004 ◽

Cited By ~ 2

Author(s):

H. Yaguchi ◽

S. Murakami ◽

N. Fujitsuna ◽

T. Shinya ◽

M. Yamada ◽

...

Keyword(s):

Aging Time ◽

Isothermal Aging ◽

Hydrogen Charge ◽

Temper Embrittlement ◽

Critical Factor ◽

Impurity Level ◽

Hydrogen Trapping ◽

Aging Behavior ◽

Diffusible Hydrogen

Long-term isothermal aging behavior up to 30,000h has been investigated in V-modified 2.25Cr-1Mo steels. When impurity elements were added, FATT in Charpy impact test vs. aging time curves showed basically of parabolic type, indicating the importance of segregation of impurities as the critical factor in controlling temper embrittlement. On the other hand, when the amount of impurities was small, FATT showed complex behavior with aging time. This suggests the importance of other factors in controlling temper embrittlement such as recovery of dislocations and enlargement of various carbide precipitates. When the degree of temper embrittlement after aging is compared in terms of the increase in FATT due to aging between the modified steels and the conventional 2.25Cr-1Mo steels, it is found to be small in the modified steel at the same impurity level (J-factor). It was also found that the modified steels showed no hydrogen embrittlement. No change was observed in FATT after hydrogen charge on the contrast to the conventional steel, which showed significant increase in FATT. This effect has been attributed to the small amount of diffusible hydrogen content in the modified steel by the presence of hydrogen trapping sites, which is present even after long-term isothermal aging.

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