A new conceptual framework for the use of hydrogen isotopes in tree rings

2020 ◽  
Author(s):  
Marco M. Lehmann ◽  
Velentina Vitali ◽  
Philipp Schuler ◽  
Matthias Saurer
Keyword(s):  
Conceptual Framework ◽  
Tree Rings ◽  
Physiological Responses ◽  
Climatic Conditions ◽  
Environmental Research ◽  
Widespread Application ◽  
Local Climate ◽  
Biochemical Processes ◽  
Hydrogen Isotope Ratios ◽  
Set Up

<p>Carbon and oxygen stable isotopes in tree-rings are successfully used in climate and environmental research, for instance for the reconstruction of past climatic conditions and corresponding physiological responses of trees to local climate. In contrast, hydrogen isotope ratios (δ<sup>2</sup>H), available also in the cellulose molecule of tree-rings, have been largely neglected. Mostly due to methodological reasons, but also because various studies found a rather poor climate information in the δ<sup>2</sup>H of tree rings. Recent studies show that the latter might be caused by isotope fractionation mechanisms that are related to plant physiological and biochemical processes rather than to climate or hydrological changes. These results also suggest that a relative use of carbon reserves and photosynthetic assimilates may explain δ<sup>2</sup>H variations in tree-rings. We therefore investigated the literature and observed strong relationships between δ<sup>2</sup>H and tree growth chronologies across various species in Switzerland, Germany, Norway, China, and India. The relationships between tree-ring growth and δ<sup>2</sup>H show a dependence to site-specific factors, climatic conditions (e.g. temperature, precipitation), and competition/light effects. Based on our findings we set up a novel conceptual framework that may allow the reconstruction of physiological responses such as carbon use strategies under varying environmental conditions. This new tool may find widespread application to identify and date, with high resolution, stressful conditions or stress-release phases that a tree or a forest ecosystem has experienced in the past.</p>

Tree-Ring Formation, Radial Increment Periodicity, and Phenology of Tree Species from a Seasonal Semi-Deciduous Forest in Southeast Brazil

IAWA Journal ◽  
2008 ◽  
Vol 29 (2) ◽  
pp. 189-207 ◽  
Author(s):  
Claudio S. Lisi ◽  
Mário Tomazello Fo ◽  
Paulo C. Botosso ◽  
Fidel A. Roig ◽  
Vivian R.B. Maria ◽  
...  
Keyword(s):  
Tree Rings ◽  
Tree Species ◽  
Deciduous Forest ◽  
Growth Ring ◽  
Climatic Conditions ◽  
Dry Season ◽  
Tree Age ◽  
Radial Increment ◽  
Future Studies ◽  
Southeast Brazil

Many tropical tree species produce growth rings in response to seasonal environmental factors that influence the activity of the vascular cambium. We applied the following methods to analyze the annual nature of treering formation of 24 tree species from a seasonal semi-deciduous forest of southeast Brazil: describing wood anatomy and phenology, counting tree rings after cambium markings, and using permanent dendrometer bands. After 7 years of systematic observations and measurements, we found the following: the trees lost their leaves during the dry season and grew new leaves at the end of the same season; trunk increment dynamics corresponded to seasonal changes in precipitation, with higher increment (active period) during the rainy season (October–April) and lower increment (dormant period) during the dry season (May–September); the number of tree rings formed after injuries to the cambium coincided with the number of years since the extraction of the wood samples. As a result of these observations, it was concluded that most study trees formed one growth ring per year. This suggests that tree species from the seasonal semi-deciduous forests of Brazil have an annual cycle of wood formation. Therefore, these trees have potential for use in future studies of tree age and radial growth rates, as well as to infer ecological and regional climatic conditions. These future studies can provide important information for the management and conservation of these endangered forests.

scholarly journals Evaluation of Red Raspberry Cultivars Used for Breeding and Commercial Growing in the Baltic Region

2017 ◽  
Vol 71 (3) ◽  
pp. 203-210 ◽  
Author(s):  
Gunārs Lācis ◽  
Irita Kota-Dombrovska ◽  
Sarmīte Strautiņa
Keyword(s):  
Genetic Resources ◽  
Genetic Material ◽  
Climatic Conditions ◽  
Parent Material ◽  
Local Climate ◽  
Political Situation ◽  
Baltic Countries ◽  
Breeding Programmes ◽  
The Baltic ◽  
Local Advanced

Abstract The structure of raspberry cultivars and genetic resources in the Baltic countries have been influenced by the historical political situation in the 20th century and climatic conditions, especially winterhardiness. The genetic resources consist of some old European and American cultivars, but mostly of cultivars and hybrids bred in Russia. Currently, targeted breeding programmes are active only in Estonia and Latvia, which aim to develop winterhardy, disease-resistant cultivars, well adapted to the local climate. Therefore, parent material for hybridisation has been chosen from local advanced hybrids and introduced cultivars suitable to the regional climatic conditions. The aim of the study was to estimate the level of genetic diversity of Rubus germplasm and assess inter-specific and intra-specific relationships using phenotypical characterisation and molecular markers. Forty one Rubus genotypes were evaluated by 41 phenotypical traits and 15 previously described SSR markers. Both characterisation approaches discovered high correspondence with pedigree and a low level of diversity. A limited amount of the diversity of raspberry genetic material has been used in various breeding programmes, despite their broad geographical origin. The obtained results indicate the need for including local wild R. idaeus plant material into breeding programmes.

scholarly journals Improving Interior Environmental Quality Using Sustainable Design in Jordanian Hospital Bedrooms

2020 ◽  
Vol 9 (3) ◽  
pp. 443
Author(s):  
Saeed Hussein Alhmoud ◽  
Çiğdem Çağnan ◽  
Enis Faik Arcan
Keyword(s):  
Interior Design ◽  
Environmental Quality ◽  
Sustainable Design ◽  
Health Sector ◽  
Green Building ◽  
Climatic Conditions ◽  
Building Assessment ◽  
The World ◽  
Set Up ◽  
The One

As the wave of sustainability is sweeping across the major countries and cities of the world, the effect of the inevitable change is finding its way through to the health sector as well. Since the main functions of the hospital include healing the patient, it aims to provide adequate health services to people. Hospitals managers should strive to realize facilities that meet a certain level of demand. This study aims to present the interior environmental quality (IEQ) of bedrooms in Jordanian hospitals and propose a solution to improve indoor environment quality using sustainable design principles. A qualitative research methodology is used in this study. A comparative analysis is made between the original set up of the hospital buildings and the present conditions in which they are in. During the research, it was found that the design to be applied for a hospital should be following the healing environmental characteristics. Besides, the design of hospitals should be made with the climatic conditions of the area in mind. In the advanced countries of the world, hospitals are generally built with extensive research and important factors such as temperature, wind direction and humidity are taken into consideration. The design for a hospital building should be assessed according to the German Green Building Assessment (DGNB) criteria. It has been found that the one-bedroom is ideal for patients because it provides the necessary privacy and also greatly reduces the spread of the disease. In hygienic practices, there should be a first-class healing environment with evidence-based medical research. It was concluded that the practices involving the use of sustainable designs can be followed with the hints received from hospitals in the advanced countries of the world. Keywords: Jordan hospital; IEQ; bedroom; interior design; healthcare; green building assessment; DGNB

scholarly journals Visual Biochemistry: modular microfluidics enables kinetic insight from time-resolved cryo-EM

2020 ◽  
Author(s):  
Märt-Erik Mäeots ◽  
Byungjin Lee ◽  
Andrea Nans ◽  
Seung-Geun Jeong ◽  
Mohammad M. N. Esfahani ◽  
...  
Keyword(s):  
Sample Preparation ◽  
Reaction Intermediates ◽  
Protein Distribution ◽  
Time Resolved ◽  
Biochemical Processes ◽  
Molecular Events ◽  
Biophysical Analysis ◽  
Common Strategy ◽  
Set Up

AbstractMechanistic understanding of biochemical reactions requires structural and kinetic characterization of the underlying chemical processes. However, no single experimental technique can provide this information in a broadly applicable manner and thus structural studies of static macromolecules are often complemented by biophysical analysis. Moreover, the common strategy of utilizing mutants or crosslinking probes to stabilize otherwise short-lived reaction intermediates is prone to trapping off-pathway artefacts and precludes determining the order of molecular events. To overcome these limitations and allow visualisation of biochemical processes at near-atomic spatial resolution and millisecond time scales, we developed a time-resolved sample preparation method for cryo-electron microscopy (trEM). We integrated a modular microfluidic device, featuring a 3D-mixing unit and a delay line of variable length, with a gas-assisted nozzle and motorised plunge-freeze set-up that enables automated, fast, and blot-free sample vitrification. This sample preparation not only preserves high-resolution structural detail but also substantially improves protein distribution across the vitreous ice. We validated the method by examining the formation of RecA filaments on single-stranded DNA. We could reliably visualise reaction intermediates of early filament growth across three orders of magnitude on sub-second timescales. Quantification of the trEM data allowed us to characterize the kinetics of RecA filament growth. The trEM method reported here is versatile, easy to reproduce and thus readily adaptable to a broad spectrum of fundamental questions in biology.

scholarly journals Evaporation suppression and energy balance of water reservoirs covered with self-assembling floating elements

2018 ◽  
Vol 22 (7) ◽  
pp. 4015-4032 ◽  
Author(s):  
Milad Aminzadeh ◽  
Peter Lehmann ◽  
Dani Or
Keyword(s):  
Energy Balance ◽  
Water Storage ◽  
Climatic Conditions ◽  
Heat Fluxes ◽  
Conservation Strategy ◽  
Radiative Energy ◽  
Water Reservoirs ◽  
Local Climate ◽  
Self Assembling ◽  
Evaporation Suppression

Abstract. The growing pressure on natural freshwater resources and the projected climate variability are expected to increase the need for water storage during rainy periods. Evaporative losses present a challenge for the efficiency of water storage in reservoirs, especially in arid regions with chronic water shortages. Among the available methods for suppressing evaporative losses, self-assembling floating elements offer a simple and scalable solution, especially for small reservoirs. The use of floating elements has often been empirically based; we thus seek a framework for systematic consideration of floating element properties, local climate and reservoir conditions to better predict evaporative loss, energy balance and heat fluxes from covered water reservoirs. We linked the energy balance of the water column with energy considerations of the floating elements. Results suggest significant suppression of evaporative losses from covered reservoirs in which incoming radiative energy is partitioned to sensible and long wave fluxes that reduce latent heat flux and thus increase the Bowen ratio over covered water reservoirs. Model findings were consistent with laboratory-scale observations using an uncovered and covered small basin. The study offers a physically based framework for testing design scenarios in terms of evaporation suppression efficiency for various climatic conditions; it hence strengthens the science in the basis of this important water resource conservation strategy.

I CEREALI NELL’ANTICA GRECIA E L’APPROVVIGIONAMENTO GRANARIO DELL’ATENE CLASSICA

2016 ◽  
Author(s):  
Ugo Fantasia
Keyword(s):  
Animal Manure ◽  
Climatic Conditions ◽  
Retail Trade ◽  
Bread Making ◽  
Ancient Greek ◽  
Basic Need ◽  
Set Up ◽  
Greek World ◽  
Main Producer

Cereals, chiefly barley, covered roughly three-quarters of the food requirements of ancient Greeks. The agrarian practices were modelled on this basic need. However, although recent studies have stressed their efforts to maximize production, climatic conditions and the scarcity of animal manure doomed the ancient Greek world to a low productivity. So the more populous poleis had to import large quantities of grain. This was the case of classical Athens, which particularly after the loss of empire in 404 BC was forced to set up a new policy. Its most important aspects were the good relations with Bosporan Kingdom in Crimea (the main producer of Triticum compactum, the most suitable grain for bread-making) and the legislation about the maritime and retail trade. This policy was relatively successful, but dependence on grain imports was for Athens a major factor of political and military weakness.

MNCs from LDCs: The case of Indian joint ventures abroad*

1982 ◽  
Vol 7 (2) ◽  
pp. 133-148
Author(s):  
K. Balakrishnan
Keyword(s):  
Public Policy ◽  
Conceptual Framework ◽  
Failure Rate ◽  
Joint Ventures ◽  
World Markets ◽  
Overseas Investment ◽  
Recent Origin ◽  
The Government ◽  
Set Up

Though Indian joint ventures are of recent origin, and the initial failure rate is high, they are gradually being recognized by the Government of India and Indian businessmen as powerful instruments to secure a foothold in world markets. Many proposals, however, went abortive for lack of a long term strategic outlook on the part of either the entrepreneurs or the respective governments. In this set up, the author discusses how public policy in India and abroad seems to have provided a push to India's overseas investment efforts. But this is not enough. And Balakrishnan delineates how and what Indian investors abroad must do to succeed in their ventures. For this, viable strategies must be evolved to identify and exploit our long term opportunities. To facilitate this process, he gives a simple conceptual framework of the product market scope for Indian joint ventures abroad.

scholarly journals Mammalian Cell-Based Immunoassay for Detection of Viable Bacterial Pathogens

2020 ◽  
Vol 11 ◽  
Author(s):  
Luping Xu ◽  
Xingjian Bai ◽  
Shivendra Tenguria ◽  
Yi Liu ◽  
Rishi Drolia ◽  
...  
Keyword(s):  
Shelf Life ◽  
Mammalian Cell ◽  
Rapid Detection ◽  
Mammalian Cells ◽  
Host Cells ◽  
Detection Time ◽  
Primary Methods ◽  
Widespread Application ◽  
Lateral Flow Assays ◽  
Set Up

Rapid detection of live pathogens is of paramount importance to ensure food safety. At present, nucleic acid-based polymerase chain reaction and antibody-based lateral flow assays are the primary methods of choice for rapid detection, but these are prone to interference from inhibitors, and resident microbes. Moreover, the positive results may neither assure virulence potential nor viability of the analyte. In contrast, the mammalian cell-based assay detects pathogen interaction with the host cells and is responsive to only live pathogens, but the short shelf-life of the mammalian cells is the major impediment for its widespread application. An innovative approach to prolong the shelf-life of mammalian cells by using formalin was undertaken. Formalin (4% formaldehyde)-fixed human ileocecal adenocarcinoma cell line, HCT-8 on 24-well tissue culture plates was used for the capture of viable pathogens while an antibody was used for specific detection. The specificity of the Mammalian Cell-based ImmunoAssay (MaCIA) was validated with Salmonella enterica serovar Enteritidis and Typhimurium as model pathogens and further confirmed against a panel of 15 S. Enteritidis strains, 8 S. Typhimurium, 11 other Salmonella serovars, and 14 non-Salmonella spp. The total detection time (sample-to-result) of MaCIA with artificially inoculated ground chicken, eggs, milk, and cake mix at 1–10 CFU/25 g was 16–21 h using a traditional enrichment set up but the detection time was shortened to 10–12 h using direct on-cell (MaCIA) enrichment. Formalin-fixed stable cell monolayers in MaCIA provide longer shelf-life (at least 14 weeks) for possible point-of-need deployment and multi-sample testing on a single plate.

scholarly journals Lead uptake and tolerance of Ricinus communis L.

2006 ◽  
Vol 18 (4) ◽  
pp. 483-489 ◽  
Author(s):  
Solange Romeiro ◽  
Ana M.M.A. Lagôa ◽  
Pedro R. Furlani ◽  
Cleide A. de Abreu ◽  
Mônica F. de Abreu ◽  
...  
Keyword(s):  
Nutrient Solution ◽  
Ricinus Communis ◽  
Block Design ◽  
Physiological Responses ◽  
Tropical Species ◽  
Lead Uptake ◽  
Nutritive Solution ◽  
Ricinus Communis L ◽  
Light Concentration ◽  
Set Up

Phytoextraction is an important technique used for the decontamination of areas polluted by lead. Consequently, an understanding of the physiological responses to tolerance of tropical species subjected to increasing levels of contamination is fundamental before considering their use as phytoextractors in contaminated areas. The objective of this study was to assess the lead (Pb) uptake and the tolerance of Ricinus communis L. The plants were cultivated in nutrient solution in a greenhouse under controlled conditions. Lead was tested at concentrations of 0, 100, 200 and 400 µmol L-1. The experimental set-up was a block design, using a 4 x 1 factorial scheme, with three replicates. Biometric analyses, photosynthesis rates, and Pb content in the nutritive solution as well as in roots and shoots were performed. In conclusion, R. communis L is a hyperaccumulator species for Pb and presents tolerance properties in lead light concentration.

Sign in / Sign up

Export Citation Format

Share Document