An extended period of episodic northern mid-latitude glaciation on Mars during the Middle to Late Amazonian: Implications for long-term obliquity history

Geology ◽  
2014 ◽  
Vol 42 (9) ◽  
pp. 763-766 ◽  
Author(s):  
Caleb I. Fassett ◽  
Joseph S. Levy ◽  
James L. Dickson ◽  
James W. Head
Keyword(s):  
2021 ◽  
Vol 30 ◽  
pp. 096368972110360
Author(s):  
Daniel Lysak ◽  
Michaela Brychtová ◽  
Martin Leba ◽  
Miroslava Čedíková ◽  
Daniel Georgiev ◽  
...  

Cryopreserved haematopoietic progenitor cells are used to restore autologous haematopoiesis after high dose chemotherapy. Although the cells are routinely stored for a long period, concerns remain about the maximum storage time and the possible negative effect of storage on their potency. We evaluated the effect of cryopreservation on the quality of peripheral stem cell grafts stored for a short (3 months) and a long (10 years) period and we compared it to native products.The viability of CD34+ cells remained unaffected during storage, the apoptotic cells were represented up to 10% and did not differ between groups. The clonogenic activity measured by ATP production has decreased with the length of storage (ATP/cell 1.28 nM in native vs. 0.63 in long term stored products, P < 0.05). Only borderline changes without statistical significance were detected when examining mitochondrial and aldehyde dehydrogenase metabolic activity and intracellular pH, showing their good preservation during cell storage. Our experience demonstrates that cryostorage has no major negative effect on stem cell quality and potency, and therefore autologous stem cells can be stored safely for an extended period of at least 10 years. On the other hand, long term storage for 10 years and longer may lead to mild reduction of clonogenic capacity. When a sufficient dose of stem cells is infused, these changes will not have a clinical impact. However, in products stored beyond 10 years, especially when a low number of CD34+ cells is available, the quality of stem cell graft should be verified before infusion using the appropriate potency assays.


2019 ◽  
Vol 11 (21) ◽  
pp. 6041 ◽  
Author(s):  
Zhang ◽  
Li ◽  
Buyantuev ◽  
Bao ◽  
Zhang

Ecosystem services management should often expect to deal with non-linearities due to trade-offs and synergies between ecosystem services (ES). Therefore, it is important to analyze long-term trends in ES development and utilization to understand their responses to climate change and intensification of human activities. In this paper, the region of Uxin in Inner Mongolia, China, was chosen as a case study area to describe the spatial distribution and trends of 5 ES indicators. Changes in relationships between ES and driving forces of dynamics of ES relationships were analyzed for the period 1979–2016 using a stepwise regression. We found that: the magnitude and directions in ES relationships changed during this extended period; those changes are influenced by climate factors, land use change, technological progress, and population growth.


2017 ◽  
Vol 2017 ◽  
pp. 1-9
Author(s):  
Beatriz Quintero Moreno ◽  
María Araque ◽  
Evelyn Mendoza

Objective. To produce two supplemented agar types in order to store pneumococci for several months at room temperature.Methods. Todd-Hewitt/Hemoglobin/Yeast/Charcoal/Agar (TH-HYC) and Todd-Hewitt/Skim-Milk/Yeast/Charcoal/Agar (TH-SYC) were used to prepare two supplemented agar types. Nineteen pneumococci isolated from patients or asymptomatic carriers displaying diverse serotypes and multilocus sequence types (MLST) were subcultured and stored onto supplemented agar types, in four different tests, at room temperature.Findings. At the end of all tests (4–6 months) all noncontaminated subcultures were viable and maintained all phenotypic characteristics. Survival-time curves revealed a slow decrease of viable CFU over time on agar types, but at the end the number of viable CFU was satisfactory (≥2+ of growth). Decreasing of CFU was significantly higher for clinical versus nasopharyngeal isolates. Subcultures contamination rates were 6.25% and 14.58% after 2 and 6 months of storage, respectively.Conclusion. TH-HYC and TH-SYC agar types allowed the viability of pneumococci with several serotypes, MLST, and genetic profiles, after 6 months of storage at room temperature. We consider that these agar types are a valid alternative to preserve pneumococci over an extended period, especially when methods as cryopreservation or lyophilization are not available, and are useful for transporting strains between laboratories.


2020 ◽  
pp. 99-112
Author(s):  
Melvin Delgado

The importance of education in a democracy can be measured from multiple perspectives, with those failing representing an opportunity lost with immediate and long-term ramifications. In global and technologically driven economies, education has ascended in significance to a point where a high school diploma is no longer a ticket to the middle class. Public education is a linchpin in the ultimate career success of students, with much expected of a system occupying such a prominent and extended period in their lives, daily and during key developmental phases. This chapter covers the usual urban public education and communities of color terrain. However, two pipelines will draw particular attention—school-to-prison and school-to-military—with an extension to include prison, too, highlighting state-sanctioned violence.


Nanoscale ◽  
2021 ◽  
Author(s):  
Ying-Hao Pai ◽  
Chun-Hua Chen

Hydrophobic Al2O3 columnar cappings have been demonstrated as promising candidates for comprehensive protection against severe rapid degradation of pristine black phosphorus even under a very high-humidity environment (RH = 85%) for an extended period.


Author(s):  
A. V. Chambers ◽  
W. R. Rodwell ◽  
M. Kelly ◽  
A. R. Hoch ◽  
A. J. Baker

In the UK, the need for the long-term management of intermediate-level radioactive wastes arises from the absence of an established deep disposal option. As a consequence there is a requirement to demonstrate the ‘passive safety’ of waste packages in stores over a necessarily lengthy period (perhaps 150 years or more). ‘Passive safety’ is taken here to imply that the waste packages themselves would remain safe without intervention; it is assumed however, that the store building and associated infrastructure would need to be actively maintained and that the store may need to be ventilated. Importantly, methods for waste storage also need to ensure that possible future options for disposal are not foreclosed. An extended period of storage suggests that emphasis will need to be placed by waste producers on understanding a number of issues such as: • the impact of corrosion on container integrity; • the assessment of container vents and other features as a pathway for the release of radioactivity; • the extent to which wastes are conditioned for storage and the selection of appropriate methods; • the generation and behaviour of toxic or flammable gases in the storage facility; and the mitigating steps that might be needed to address adverse impacts (e.g. the type of ventilation that the store requires). In this paper, we review the requirements and current state of knowledge relevant to the assessment of operational releases of radioactive, flammable and toxic gases from wastes in long-term interim storage.


Author(s):  
Simone Amendola ◽  
Martin Plöderl ◽  
Michael P Hengartner

Abstract Background Ecological studies have explored associations between suicide rates and antidepressant prescriptions in the population, but most of them are limited as they analyzed short-term correlations that may be spurious. The aim of this long-term study was to examine whether trends in suicide rates changed in three European countries when the first antidepressants were introduced in 1960 and when prescription rates increased steeply after 1990 with the introduction of the serotonin reuptake inhibitors (SSRIs). Methods Data were extracted from the WHO Mortality Database. Suicide rates were calculated for people aged 10–89 years from 1951–2015 for Italy, 1955–2016 for Austria and 1951–2013 for Switzerland. Trends in suicide rates stratified by gender were analyzed using joinpoint regression models. Results There was a general pattern of long-term trends that was broadly consistent across all three countries. Suicide rates were stable or decreasing during the 1950s and 1960s, they rose during the 1970s, peaked in the early 1980s and thereafter they declined. There were a few notable exceptions to these general trends. In Italian men, suicide rates increased until 1997, then fell sharply until 2006 and increased again from 2006 to 2015. In women from all three countries, there was an extended period during the 2000s when suicide rates were stable. No trend changes occurred around 1960 or 1990. Conclusions The introduction of antidepressants around 1960 and the sharp increase in prescriptions after 1990 with the introduction of the SSRIs did not coincide with trend changes in suicide rates in Italy, Austria or Switzerland.


1984 ◽  
Vol 247 (3) ◽  
pp. R595-R599 ◽  
Author(s):  
H. Tsukamoto ◽  
R. D. Reidelberger ◽  
S. W. French ◽  
C. Largman

An improved methodology is described for long-term venous and gastric cannulation in the rat. The long-term efficacy of the cannulas for blood sampling and intragastric infusion of liquid diet was determined in 18 rats. No animals died after surgery, and weight gain was normal. During the first 6 wk, blood could be drawn repetitively in 94% of the rats, and continuous intragastric infusion of diet was maintained in all the animals. For an extended period of 11 wk, success rates for blood sampling and dietary infusion were 75 and 100%, respectively. Standard hematological, histopathological, and clinical laboratory tests showed no abnormal changes. Furthermore, plasma corticosterone levels were consistently low (0.5 +/- 0.11 to 1.52 +/- 0.55 micrograms/dl) from the third postoperative day throughout a period of 6 wk, indicating that animals were under minimal stress.


2010 ◽  
Vol 148-149 ◽  
pp. 439-442
Author(s):  
Xi Hong Li ◽  
Jing Wang ◽  
Ling Yan Ge ◽  
Sen Wan

In this study, effects of Modified Atmosphere (MA) packaging on the quality of rice after a long term storage at room temperature have been investigated. PVC films with different thicknesses and woven bag were used as the package materials for rice samples. Results showed that MA packaging had a significant effect on the quality of the rice. After an extended period of storage, the rice in woven bag showed most severe quality deterioration compared to those stored in PVC packages. Rice packed in 0.05 mm PVC film package has the lowest value of total acid among all samples. The increase of fatty acid content in rice packed in 0.03 mm film, 0.05 mm film, 0.08 mm film and 0.12 mm film was 38.58 mg KOH/100g, 18.96 mg KOH/100g, 26.83 mg KOH/100g and 32.64 mg KOH/100g, respectively. The volatile aldehyde components accumulated in the stored rice are mainly acetaldehyde, valeraldehyde and hexanal. Small package with a MA has obvious benefits in regulating the metabolism and accumulation of volatile aldehyde components in the rice. Rice samples stored in a package of 0.05mm film had the lowest value of volatile aldehyde, while those in 0.03mm film had the highest value. This study suggests that MA packaging with a PVC film of 0.05 mm shows the best effects in maintaining the quality of rice after an extended period of storage (3 to 5 years).


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