Radiocarbon dating of Chinese Ancient Tea Trees

Radiocarbon ◽  
2019 ◽  
Vol 61 (6) ◽  
pp. 1741-1748
Author(s):  
Jia Chen ◽  
Hongtao Shen ◽  
Kimikazu Sasa ◽  
Haihui Lan ◽  
Tetsuya Matsunaka ◽  
...  
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Radial Growth ◽  
Accurate Determination ◽  
Annual Rings ◽  
The World ◽  
Automated Sample Preparation ◽  
The University

ABSTRACTThe jungles of Linyun and Longlin Autonomous Prefecture, located in the heart of the southwestern Guangxi Zhuang Autonomous Region of China, are home to the oldest tea trees (Camellia sinensis) in the world. In the absence of regular annual rings, radiocarbon (14C) dating is one of the most powerful tools that can assist in the determination of the ages and growth rates of these plants. In this work, cores were extracted from large ancient tea trees in a central Longlin rain forest; extraction of carbon was performed with an automated sample preparation system. The 14C levels in the tree cores were measured using accelerator mass spectrometry (AMS) at the University of Tsukuba. These measurements indicated that contrary to conventional views, the ages of trees in these forests range up to ~700 years, and the growth rate of this species is notably slow, exhibiting a long-term radial growth rate of 0.039±0.006 cm/yr. It was demonstrated that 14C analyses provide accurate determination of ages and growth rates for subtropical wild tea trees.

Approach to Assessment of Corrosion Growth in Pipelines

2002 ◽  
Author(s):  
Bill Gu ◽  
Richard Kania ◽  
Sandeep Sharma ◽  
Ming Gao
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Assessment Tool ◽  
Accurate Determination ◽  
Soil Drainage ◽  
Corrosion Condition ◽  
Preliminary Corrosion ◽  
Corrosion Defects ◽  
Growth Assessment

Two key components of corrosion growth assessment in pipelines are accurate determination of corrosion growth rate and application of corrosion growth to future integrity of a pipeline. PII has developed a corrosion growth assessment tool, Run Comparison (RunCom) software that allows accurate determination of corrosion growth. RunCom compares the raw signals of the same defect present in two inspection runs to report the real active corrosion defects and their growth with less error. Since variations in corrosion growth along the pipeline can be significant, a single value of average or maximum corrosion growth rate does not represent the corrosion condition of the pipeline and could result in a conservative or non-conservative conclusion for future integrity. PII introduces a Decision Tree Analysis method to categorize the corroded regions along the pipeline and calculate the mean corrosion growth rates in these specific areas. Relationships between corrosion growth rate and defect geometry are also identified. The influence of soil, drainage, and topography on corrosion rates is examined to determine representative corrosion growth rates along the pipeline. A systematic approach incorporating statistical analysis with mechanistic understanding of corrosion for preliminary corrosion assessment of pipeline systems is discussed.

Unambiguous and Low-Cost Determination of Growth Rates and Ages of Tropical Trees and Palms

Radiocarbon ◽  
2014 ◽  
Vol 56 (1) ◽  
pp. 39-52 ◽  
Author(s):  
Jorge I del Valle ◽  
Juan R Guarín ◽  
Carlos A Sierra
Keyword(s):  
Growth Rates ◽  
Sustainable Forest Management ◽  
Low Cost ◽  
Accurate Determination ◽  
Tropical Trees ◽  
Forest Inventories ◽  
Management Plans ◽  
Cost Determination

The determination of the age of tropical trees and palms is of significant importance for ecological studies and designing sustainable forest management plans. Radiocarbon is a powerful tool that can potentially help the determination of ages and growth rates of these plants. However, the application of 14C analyses has one important problem for trees without annual rings and palms: the calibration of 14C measurements with common programs such as CALIBomb or OxCal gives erroneous determinations for wood formed between AD 1954 and 1964. This problem is illustrated here using samples from a tropical tree (Otoba gracilipes) and a tropical palm (Oenocarpus bataua). This study shows how the use of two adjacent samples can help to unambiguously determine the real age of the samples and their mean growth rates. For comparison, long-term growth measurements for both species were used and it was determined that 14C analyses provide accurate determination of growth rates for tropical trees and palms. Furthermore, the application of 14C analyses in palms allows the determination of the rosette stage, rarely quantified in forest inventories and life-history studies.

Engineering for good: A case of community driven engineering innovation

2018 ◽  
Vol 6 (1) ◽  
Author(s):  
Chinweike Eseonu ◽  
Martin A Cortes
Keyword(s):  
Engineering Students ◽  
Technology Innovation ◽  
Local Communities ◽  
First Year ◽  
Engineering Curriculum ◽  
Engineering Design Process ◽  
The World ◽  
The University ◽  
Social Consideration

There is a culture of disengagement from social consideration in engineering disciplines. This means that first year engineering students, who arrive planning to change the world through engineering, lose this passion as they progress through the engineering curriculum. The community driven technology innovation and investment program described in this paper is an attempt to reverse this trend by fusing community engagement with the normal engineering design process. This approach differs from existing project or trip based approaches – outreach – because the focus is on local communities with which the university team forms a long-term partnership through weekly in-person meetings and community driven problem statements – engagement.

scholarly journals Using MoS2/Fe3O4 as Ion-Electron Transduction Layer to Manufacture All-Solid-State Ion-Selective Electrode for Determination of Serum Potassium

Chemosensors ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 155
Author(s):  
Yan Su ◽  
Ting Liu ◽  
Caiqiao Song ◽  
Aiqiao Fan ◽  
Nan Zhu ◽  
...  
Keyword(s):  
High Performance ◽  
Accurate Determination ◽  
Water Layer ◽  
Ion Selective Electrode ◽  
Potential Response ◽  
Selective Electrode ◽  
Response Measurement ◽  
Long Term Stability

As an essential electrolyte for the human body, the potassium ion (K+) plays many physiological roles in living cells, so the rapid and accurate determination of serum K+ is of great significance. In this work, we developed a solid-contact ion-selective electrode (SC-ISE) using MoS2/Fe3O4 composites as the ion-to-electron transducer to determine serum K+. The potential response measurement of MoS2/Fe3O4/K+-ISE shows a Nernst response by a slope of 55.2 ± 0.1 mV/decade and a low detection limit of 6.3 × 10−6 M. The proposed electrode exhibits outstanding resistance to the interference of O2, CO2, light, and water layer formation. Remarkably, it also presents a high performance in potential reproducibility and long-term stability.

scholarly journals Visualizing the Bohr effect in hemoglobin: neutron structure of equine cyanomethemoglobin in the R state and comparison with human deoxyhemoglobin in the T state

2016 ◽  
Vol 72 (7) ◽  
pp. 892-903 ◽  
Author(s):  
Steven Dajnowicz ◽  
Sean Seaver ◽  
B. Leif Hanson ◽  
S. Zoë Fisher ◽  
Paul Langan ◽  
...  
Keyword(s):  
Structural Changes ◽  
Accurate Determination ◽  
Bohr Effect ◽  
Salt Bridges ◽  
Histidine Residues ◽  
Regions Of Stability ◽  
The Individual ◽  
T State

Neutron crystallography provides direct visual evidence of the atomic positions of deuterium-exchanged H atoms, enabling the accurate determination of the protonation/deuteration state of hydrated biomolecules. Comparison of two neutron structures of hemoglobins, human deoxyhemoglobin (T state) and equine cyanomethemoglobin (R state), offers a direct observation of histidine residues that are likely to contribute to the Bohr effect. Previous studies have shown that the T-state N-terminal and C-terminal salt bridges appear to have a partial instead of a primary overall contribution. Four conserved histidine residues [αHis72(EF1), αHis103(G10), αHis89(FG1), αHis112(G19) and βHis97(FG4)] can become protonated/deuterated from the R to the T state, while two histidine residues [αHis20(B1) and βHis117(G19)] can lose a proton/deuteron. αHis103(G10), located in the α1:β1dimer interface, appears to be a Bohr group that undergoes structural changes: in the R state it is singly protonated/deuterated and hydrogen-bonded through a water network to βAsn108(G10) and in the T state it is doubly protonated/deuterated with the network uncoupled. The very long-term H/D exchange of the amide protons identifies regions that are accessible to exchange as well as regions that are impermeable to exchange. The liganded relaxed state (R state) has comparable levels of exchange (17.1% non-exchanged) compared with the deoxy tense state (T state; 11.8% non-exchanged). Interestingly, the regions of non-exchanged protons shift from the tetramer interfaces in the T-state interface (α1:β2and α2:β1) to the cores of the individual monomers and to the dimer interfaces (α1:β1and α2:β2) in the R state. The comparison of regions of stability in the two states allows a visualization of the conservation of fold energy necessary for ligand binding and release.

scholarly journals Organizational and pedagogical conditions for arranging educational practice in the process of vocational training of future managers

2021 ◽  
pp. 40-53
Author(s):  
Mikhail Sergeevich Pasholikov
Keyword(s):  
Vocational Training ◽  
Practical Importance ◽  
Educational Practice ◽  
Educational Activity ◽  
Institutions Of Higher Education ◽  
State Pedagogical ◽  
Internship Programs ◽  
The University

This article is dedicated to determination of organizational and pedagogical conditions for arranging educational practice in the process of vocational training of future managers in the university. The relevance of this topic is substantiated by dissatisfaction of the pedagogues, students and employers’ representatives with the results of educational practice. The author compares the international models of management education, and highlights the key differences in the Russian and foreign approaches towards arranging educational practice for the bachelors in management. The author describes the basic organizational and pedagogical conditions for improving the effectiveness of educational activity, implemented in Herzen State Pedagogical University of Russia within the framework of the Bachelor’s Program in Management. The novelty of this research consists in the proposal of criteria and indicators for assessing the results of organization of educational practice from the perspective satisfaction of its subjects, as well in elucidation of the key mechanisms for improving the stages of training and conducting educational practice, such as individualization of the process of vocational training of future managers, establishment of long-term relations between the graduate departments and employers’ representatives, continuous improvement of the content and mechanisms of its organization. Practical importance of this work consists in the possibility of application of the selected organizational and pedagogical conditions for arranging educational practice in development and implementation by the institutions of higher education of the basic programs of vocational education for training future specialists; development of  the programs for educational, industrial and other types of practices; as well as creation of the corporate internship programs.

scholarly journals Prospects for Vietnam’s Economy in 2013

2013 ◽  
Vol 215 ◽  
pp. 02-11
Author(s):  
NGÂN TRẦN HOÀNG
Keyword(s):  
Economic Growth ◽  
Growth Rate ◽  
World Economy ◽  
Inflation Rate ◽  
Economic Restructuring ◽  
Short Term ◽  
Economic Growth Model ◽  
The World ◽  
Global Growth

In 2012, Vietnam?s economy faced great challenges. The world economy experienced more difficulties and complicated upheavals. International trade fell drastically while global growth rate was lower than predicted target, which affected badly the Vietnamese economy because of its full integration into the world economy and large openness. In this context, principal targets set for 2013 are macroeconomic stability, lower inflation rate, higher growth rate, three strategic breakthroughs associated with restructuring of the economy, and a new economic growth model. This paper analyzes obstacles to Vietnam?s economic growth, and offers short-term solutions to bottlenecks and long-term ones to the economic restructuring.

An Evaluation of RNA–DNA Ratio as a Measure of Long-Term Growth in Fish Populations

1973 ◽  
Vol 30 (2) ◽  
pp. 195-199 ◽  
Author(s):  
Terry A. Haines
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Growth Rates ◽  
Population Growth Rate ◽  
Environmental Changes ◽  
Age Distribution ◽  
Smallmouth Bass ◽  
Fish Populations ◽  
Population Growth Rates

The value of RNA–DNA ratio as a measure of long-term growth of fish populations under semi-natural conditions and when subjected to environmental manipulations was determined. Populations of carp and smallmouth bass of known age distribution were established in artificial ponds maintained at two fertility levels. After 15 months, population growth rates (as percent increase in weight) and RNA–DNA ratios of muscle tissue from selected fish were measured. Each species exhibited a range of population growth rates. The relation between population growth rate and individual fish RNA–DNA ratio for each species was significant. When reproduction occurred, the relation was not significant unless young-of-the-year fish were excluded from population growth rate calculations. Age of fish was also found to have an important effect on RNA–DNA ratio, with the ratio being higher in younger fish.RNA–DNA ratio can be a reliable indicator of long-term population growth in fish when population age structure is known and recruitment is controlled. The method has potential for use in detecting response to environmental changes before growth rate changes become severe.

ABSTRACT

PEDIATRICS ◽  
1996 ◽  
Vol 98 (1) ◽  
pp. 44-44
Keyword(s):  
Natural Disasters ◽  
Task Force ◽  
American Psychological Association ◽  
The United States ◽  
Psychological Needs ◽  
The World ◽  
Preparation Phase ◽  
Important Field ◽  
The University

Pediatricians throughout the world are becoming aware of the severe phychological reactions among children in man-made and natural disasters, especially in war-torn areas of the world. This paper is the second of two by a Task Force of the American Psychological Association and is focused especially on interventions. There has been relatively little attention to the needs of children, especially their psychological needs. The Task Force points out the need to have a predisaster preparation phase, a short-term intervention, and a long-term intervention phase. Most of the literature reviewed in this paper is related to natural disasters in the United States. However, it is likely that the same principles will apply to dealing with children in war-torn areas of the world. The Task Force makes a strong plea, however, for stronger evaluation of disaster-related interventions. The American Academy of Pediatrics is developing, in collaboration with Dr Karen Olness' program at Case Western Reserve University and Dr Fred Burkle's program at the University of Hawaii, a program that prepares a multidisciplinary team for crisis intervention in times of disaster, both natural and man-made. Interventions with children in disasters are clearly an emerging and very important field for all who care for children.

scholarly journals Radial Growth Patterns Associated with Tree Mortality in Nothofagus pumilio Forest

Forests ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 489 ◽  
Author(s):  
Milagros Rodríguez-Catón ◽  
Ricardo Villalba ◽  
Ana Srur ◽  
A. Park Williams
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Forest Dynamics ◽  
Radial Growth ◽  
Tree Mortality ◽  
Growth Patterns ◽  
Severe Drought ◽  
Nothofagus Pumilio ◽  
Total Size ◽  
Growth Trends

Tree mortality is a key process in forest dynamics. Despite decades of effort to understand this process, many uncertainties remain. South American broadleaf species are particularly under-represented in global studies on mortality and forest dynamics. We sampled monospecific broadleaf Nothofagus pumilio forests in northern Patagonia to predict tree mortality based on stem growth. Live or dead conditions in N. pumilio trees can be predicted with high accuracy using growth rate as an explanatory variable in logistic models. In Paso Córdova (CO), Argentina, where the models were calibrated, the probability of death was a strong negative function of radial growth, particularly during the six years prior to death. In addition, negative growth trends during 30 to 45 years prior to death increased the accuracy of the models. The CO site was affected by an extreme drought during the summer 1978–1979, triggering negative trends in radial growth of many trees. Individuals showing below-average and persistent negative trends in radial growth are more likely to die than those showing high growth rates and positive growth trends in recent decades, indicating the key role of droughts in inducing mortality. The models calibrated at the CO site showed high verification skill by accurately predicting tree mortality at two independent sites 76 and 141 km away. Models based on relative growth rates showed the highest and most balanced accuracy for both live and dead individuals. Thus, the death of individuals across different N. pumilio sites was largely determined by the growth rate relative to the total size of the individuals. Our findings highlight episodic severe drought as a triggering mechanism for growth decline and eventual death for N. pumilio, similar to results found previously for several other species around the globe. In the coming decades, many forests globally will be exposed to more frequent and/or severe episodes of reduced warm-season soil moisture. Tree-ring studies such as this one can aid prediction of future changes in forest productivity, mortality, and composition.

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