Seasonal changes in carbohydrates and water content predict dynamics of frost hardiness in various temperate tree species

2021 ◽  
Author(s):  
Romain Baffoin ◽  
Guillaume Charrier ◽  
Anne-Emilie Bouchardon ◽  
Marc Bonhomme ◽  
Thierry Améglio ◽  
...  
Keyword(s):  
Water Content ◽  
Tree Species ◽  
Large Scale ◽  
Early Stage ◽  
Model Performance ◽  
Frost Tolerance ◽  
Frost Hardiness ◽  
Soluble Carbohydrate ◽  
Osmotic Effect ◽  
Wide Range

Abstract Predicting tree frost tolerance is critical to select adapted species according to both the current and predicted future climate. The relative change in water to carbohydrate ratio is a relevant trait to predict frost acclimation in branches from many tree species. The objective of this study is to demonstrate the interspecific genericity of this approach across nine tree species. In the studied angiosperm species, frost hardiness dynamics were best correlated to a decrease in water content at the early stage of acclimation (summer and early autumn). Subsequently, frost hardiness dynamics were more tightly correlated to soluble carbohydrate contents until spring growth resumption. Based on different model formalisms, we predicted frost hardiness at different clade levels (angiosperms, family, genus and species) with high to moderate accuracy (1.5–6.0°C RMSE) and robustness (2.8–6.1°C RMSEP). The TOT model, taking all soluble carbohydrate and polyols into account, was more effective and adapted for large scale studies aiming to explore frost hardiness across a wide range of species. The ISC model taking the individual contribution of each soluble carbohydrate molecule into account was more efficient at finer scale such as family or species. The ISC model performance also suggests that the role of solutes cannot be reduced to a 'bulk' osmotic effect as could be computed if all of them were located in a single, common, compartment. This study provides sets of parameters to predict frost hardiness in a wide range of species, and clues in targeting specific carbohydrate molecules to improve frost hardiness.

scholarly journals Tree canopy arthropods have idiosyncratic responses to plant ecophysiological traits in a warm temperate forest complex

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Rudi C. Swart ◽  
Michael J. Samways ◽  
Francois Roets
Keyword(s):  
Tree Species ◽  
Temperate Forest ◽  
Large Scale ◽  
Single Species ◽  
Tree Canopy ◽  
Natural Forests ◽  
Individual Tree ◽  
Arthropod Diversity ◽  
Host Trees ◽  
Wide Range

AbstractBiodiversity studies on forest canopies often have narrow arthropod taxonomic focus, or refer to a single species of tree. In response, and to better understand the wide range of drivers of arthropod diversity in tree canopies, we conducted a large-scale, multi-taxon study which (a) included effect of immediate surroundings of an individual tree on plant physiological features, and (b), how these features affect compositional and functional arthropod diversity, in a warm, southern Afro-temperate forest. We found that tree species differed significantly in plant physiological features and arthropod diversity patterns. Surprisingly, we found negative correlation between surrounding canopy cover, and both foliar carbon and arthropod diversity in host trees, regardless of tree species. Subtle, tree intraspecific variation in physiological features correlated significantly with arthropod diversity measures, but direction and strength of correlations differed among tree species. These findings illustrate great complexity in how canopy arthropods respond to specific tree species, to immediate surroundings of host trees, and to tree physiological features. We conclude that in natural forests, loss of even one tree species, as well as homogenization of the crown layer and/or human-induced environmental change, could lead to profound and unpredictable canopy arthropod biodiversity responses, threatening forest integrity.

scholarly journals Analysis and Reduction of Systematic Errors through a Seamless Approach to Modeling Weather and Climate

2010 ◽  
Vol 23 (22) ◽  
pp. 5933-5957 ◽  
Author(s):  
G. M. Martin ◽  
S. F. Milton ◽  
C. A. Senior ◽  
M. E. Brooks ◽  
S. Ineson ◽  
...  
Keyword(s):  
Time Scales ◽  
Land Surface ◽  
Large Scale ◽  
Climate Models ◽  
Spatial Scales ◽  
Full Range ◽  
Model Development ◽  
Model Performance ◽  
Systematic Errors ◽  
Wide Range

Abstract The reduction of systematic errors is a continuing challenge for model development. Feedbacks and compensating errors in climate models often make finding the source of a systematic error difficult. In this paper, it is shown how model development can benefit from the use of the same model across a range of temporal and spatial scales. Two particular systematic errors are examined: tropical circulation and precipitation distribution, and summer land surface temperature and moisture biases over Northern Hemisphere continental regions. Each of these errors affects the model performance on time scales ranging from a few days to several decades. In both cases, the characteristics of the long-time-scale errors are found to develop during the first few days of simulation, before any large-scale feedbacks have taken place. The ability to compare the model diagnostics from the first few days of a forecast, initialized from a realistic atmospheric state, directly with observations has allowed physical deficiencies in the physical parameterizations to be identified that, when corrected, lead to improvements across the full range of time scales. This study highlights the benefits of a seamless prediction system across a wide range of time scales.

scholarly journals Prioritization of COPD protein biomarkers, based on a systematic study of the literature

2016 ◽  
Vol 1 (1) ◽  
pp. 4 ◽  
Author(s):  
Sara Ongay ◽  
Frank Klont ◽  
Peter Horvatovich ◽  
Rainer Bischoff ◽  
Nick HT Ten Hacken
Keyword(s):  
Large Scale ◽  
Complex Disease ◽  
Clinical Decision Making ◽  
Early Stage ◽  
Clinical Decision ◽  
Chronic Obstructive ◽  
Protein Biomarkers ◽  
Lung Function Decline ◽  
Comprehensive Overview ◽  
Wide Range

Chronic Obstructive Pulmonary Disease (COPD) is a chronic lung disease mostly due to smoking and until now diagnosed by spirometry (post bronchodilator FEV1/FVC <70%). However, in spite of the usefulness of FEV1 as diagnostic and prognostic tool, it has proven to be a weak indicator of future exacerbations, unable to predict lung function decline within COPD patients, as well as unable to identify the smokers “susceptible” to developing COPD at an early stage. Thus, there is an urgent need for biomarkers that address these questions and support clinical decision making in the diagnosis and treatment of (early) COPD. In this respect, considerable efforts have been devoted to identifying protein biomarkers that enable a better understanding of this complex disease and leading to better diagnostic and prognostic tools. However, in spite of the wide range of candidates that have been suggested as potentially useful COPD biomarkers, most remained at the level of the initial discovery, and only fibrinogen has been approved by the Food and Drug Administration (FDA) as predictor for all-cause mortality and COPD exacerbations. There is thus a need for future investigations of these biomarkers in large-scale and well characterized studies in order to prove their usefulness as surrogate endpoints. Based on this, the aim of the present review is to advance COPD biomarker development by providing a comprehensive overview of protein biomarker candidates which have been evaluated in clinical studies and prioritize them according to their potential of becoming valid, clinically useful COPD biomarkers.

Validation of process-based sand wave models: applying a linear and nonlinear sand wave model to the Netherlands Continental Shelf

2020 ◽  
Author(s):  
Geert Campmans ◽  
Pieter Roos ◽  
Thaiënne Van Dijk ◽  
Suzanne Hulscher
Keyword(s):  
Continental Shelf ◽  
Linear Model ◽  
Large Scale ◽  
Model Performance ◽  
Sand Wave ◽  
Earth Surface ◽  
Geophysical Research ◽  
Wave Dynamics ◽  
Wide Range ◽  
Linear And Nonlinear

&lt;p&gt;Tidal sand waves are dynamic large-scale bed forms occurring in tide-dominated, sandy shelf seas such as the North Sea. Since they may interfere with various activities, understanding sand wave dynamics is important from a practical point of view. Recently, two process-based model studies were carried out to investigate the influence of storm processes on sand wave dynamics (Campmans et al., CSR2017; JGR2018). While this type of model gives insight in the morphodynamic mechanisms, quantitative comparison with field observations remains a challenge.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;Here we present a systematic validation of the afore mentioned linear and nonlinear models, against a wide range of sand wave observations from the entire Netherlands Continental Shelf (Damen et al., JGR2018). Specifically, from the available locations with sand wave observations and environmental characteristics, we have chosen a grid for calibration and, staggered to that, a grid for validation. For the so-called calibration locations, we tuned the linear model (using local environmental conditions) in order to minimize the difference between observed and modelled wavelengths. Next, on the validation locations, we used the thus obtained parameter settings (location-independent values of slip parameter and effective wave period) to test our model performance, both in the linear and nonlinear regime. First results demonstrate fair agreement for the wavelengths from the linear model and indicate a systematic overestimation of sand wave heights by the nonlinear model.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;References&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;Campmans, G.H.P., Roos, P.C., De Vriend, H.J., Hulscher, S.J.M.H., 2017.&amp;#160; Modeling the influence of storms on sand wave formation: A linear stability approach. Continental Shelf Research 137, 103&amp;#8211;116.&lt;/p&gt;&lt;p&gt;Campmans, G.H.P., Roos, P.C., De Vriend, H.J., Hulscher, S.J.M.H., 2018. The influence of storms on sand wave evolution: a nonlinear idealized modeling approach. Journal of Geophysical Research: Earth Surface 123, 2070-2086.&lt;/p&gt;&lt;p&gt;Damen, J.M., Van Dijk, T.A.G.P., Hulscher, S.J.M.H., 2018. Spatially varying environmental properties controlling observed sand wave morphology. Journal of Geophysical Research: Earth Surface 123, 262-280.&lt;/p&gt;

Electron microscopy study of reactively sputter-deposited Ti/N films on silicon

1992 ◽  
Vol 50 (2) ◽  
pp. 1362-1363
Author(s):  
V. C. Kannan ◽  
A. K. Singh ◽  
R. B. Irwin ◽  
S. Chittipeddi ◽  
F. D. Nkansah ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
Large Scale ◽  
Hexagonal Phase ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Process Conditions ◽  
Tin Films ◽  
Wide Range ◽  
Fcc Phase ◽  
Circuits Vlsi

Titanium nitride (TiN) films have historically been used as diffusion barrier between silicon and aluminum, as an adhesion layer for tungsten deposition and as an interconnect material etc. Recently, the role of TiN films as contact barriers in very large scale silicon integrated circuits (VLSI) has been extensively studied. TiN films have resistivities on the order of 20μ Ω-cm which is much lower than that of titanium (nearly 66μ Ω-cm). Deposited TiN films show resistivities which vary from 20 to 100μ Ω-cm depending upon the type of deposition and process conditions. TiNx is known to have a NaCl type crystal structure for a wide range of compositions. Change in color from metallic luster to gold reflects the stabilization of the TiNx (FCC) phase over the close packed Ti(N) hexagonal phase. It was found that TiN (1:1) ideal composition with the FCC (NaCl-type) structure gives the best electrical property.

Biscogniauxia (Hypoxylon) Canker or Dieback in Trees

EDIS ◽  
2017 ◽  
Vol 2017 (6) ◽  
Author(s):  
Claudia Paez ◽  
Jason A. Smith
Keyword(s):  
Water Stress ◽  
Tree Species ◽  
Soil Compaction ◽  
Urban Areas ◽  
Root Disease ◽  
Poor Health ◽  
Green Spaces ◽  
Opportunistic Pathogens ◽  
Wide Range ◽  
Quercus Spp

Biscogniauxia canker or dieback (formerly called Hypoxylon canker or dieback) is a common contributor to poor health and decay in a wide range of tree species (Balbalian & Henn 2014). This disease is caused by several species of fungi in the genus Biscogniauxia (formerly Hypoxylon). B. atropunctata or B. mediterranea are usually the species found on Quercus spp. and other hosts in Florida, affecting trees growing in many different habitats, such as forests, parks, green spaces and urban areas (McBride & Appel, 2009).  Typically, species of Biscogniauxia are opportunistic pathogens that do not affect healthy and vigorous trees; some species are more virulent than others. However, once they infect trees under stress (water stress, root disease, soil compaction, construction damage etc.) they can quickly colonize the host. Once a tree is infected and fruiting structures of the fungus are evident, the tree is not likely to survive especially if the infection is in the tree's trunk (Anderson et al., 1995).

Konkurrenz zwischen Stieleiche und Buche auf Lothar-Sturmflächen | Competition between pedunculate oak and European beech on Lothar windthrow areas

2009 ◽  
Vol 160 (5) ◽  
pp. 114-123 ◽  
Author(s):  
Daniel Otto ◽  
Sven Wagner ◽  
Peter Brang
Keyword(s):  
Large Scale ◽  
Early Stage ◽  
Tree Height ◽  
European Beech ◽  
Threshold Value ◽  
Test Methods ◽  
Permanent Plots ◽  
Pedunculate Oak ◽  
Competitive Pressure ◽  
Competition Index

The competitive pressure of naturally regenerated European beech (Fagus sylvatica) saplings on planted pedunculate oak (Quercus robur) was investigated on two 1.8 ha permanent plots near Habsburg and Murten (Switzerland). The plots were established with the aim to test methods of artificial oak regeneration after large-scale windthrow. On both plots, 80 oaks exposed to varying levels of competitive pressure from at most 10 neighbouring beech trees were selected. The height of each oak as well as stem and branch diameters were measured. The competitive pressure was assessed using Schütz's competition index, which is based on relative tree height, crown overlap and distance from competing neighbours. Oak trees growing without or with only slight competition from beech were equally tall, while oaks exposed to moderate to strong competition were smaller. A threshold value for the competition index was found above which oak height decreased strongly. The stem and branch diameters of the oaks started to decrease even if the competition from beech was slight, and decreased much further with more competition. The oak stems started to become more slender even with only slight competition from beech. On the moderately acid beech sites studied here, beech grow taller faster than oak. Thus where beech is competing with oak and the aim is to maintain the oak, competitive pressure on the oak must be reduced at an early stage. The degree of the intervention should, however, take the individual competitive interaction into account, with more intervention if the competition is strong.

THE SOME QUESTIONS OF AUTONOMOUS MOTION AND MANAGEMENT OF LAND-MOBILE ROBOTIC COMPLEXES FOR UKRAINIAN GROUND FORCESE

2019 ◽  
pp. 53-58
Author(s):  
О. Кravchuk ◽  
V. Symonenkov ◽  
I. Symonenkova ◽  
O. Hryhorev
Keyword(s):  
Large Scale ◽  
Armed Forces ◽  
Distributed Information ◽  
Wide Range ◽  
Highly Effective ◽  
Information Management Systems ◽  
Robotic Devices ◽  
Principles And Standards ◽  
And Control ◽  
The Eu

Today, more than forty countries of the world are engaged in the development of military-purpose robots. A number of unique mobile robots with a wide range of capabilities are already being used by combat and intelligence units of the Armed forces of the developed world countries to conduct battlefield intelligence and support tactical groups. At present, the issue of using the latest information technology in the field of military robotics is thoroughly investigated, and the creation of highly effective information management systems in the land-mobile robotic complexes has acquired a new phase associated with the use of distributed information and sensory systems and consists in the transition from application of separate sensors and devices to the construction of modular information subsystems, which provide the availability of various data sources and complex methods of information processing. The purpose of the article is to investigate the ways to increase the autonomy of the land-mobile robotic complexes using in a non-deterministic conditions of modern combat. Relevance of researches is connected with the necessity of creation of highly effective information and control systems in the perspective robotic means for the needs of Land Forces of Ukraine. The development of the Armed Forces of Ukraine management system based on the criteria adopted by the EU and NATO member states is one of the main directions of increasing the effectiveness of the use of forces (forces), which involves achieving the principles and standards necessary for Ukraine to become a member of the EU and NATO. The inherent features of achieving these criteria will be the transition to a reduction of tasks of the combined-arms units and the large-scale use of high-precision weapons and land remote-controlled robotic devices. According to the views of the leading specialists in the field of robotics, the automation of information subsystems and components of the land-mobile robotic complexes can increase safety, reliability, error-tolerance and the effectiveness of the use of robotic means by standardizing the necessary actions with minimal human intervention, that is, a significant increase in the autonomy of the land-mobile robotic complexes for the needs of Land Forces of Ukraine.

Stirring and aeration system for the upgrading of small waste water treatment plants

1994 ◽  
Vol 29 (12) ◽  
pp. 149-156 ◽  
Author(s):  
Marcus Höfken ◽  
Katharina Zähringer ◽  
Franz Bischof
Keyword(s):  
Waste Water ◽  
Water Treatment ◽  
Large Scale ◽  
Waste Water Treatment ◽  
Water Treatment Plants ◽  
Waste Water Treatment Plants ◽  
Basic Fluid ◽  
Aeration System ◽  
Technical Realization ◽  
Wide Range

A novel agitating system has been developed which allows for individual or combined operation of stirring and aeration processes. Basic fluid mechanical considerations led to the innovative hyperboloid design of the stirrer body, which ensures high efficiencies in the stirring and the aeration mode, gentle circulation with low shear forces, excellent controllability, and a wide range of applications. This paper presents the basic considerations which led to the operating principle, the technical realization of the system and experimental results in a large-scale plant. The characteristics of the system and the differences to other stirring and aeration systems are illustrated. Details of the technical realization are shown, which conform to the specific demands of applications in the biological treatment of waste water. Special regard is given to applications in the upgrading of small compact waste water treatment plants.

Thin structure of heterogeneous and multiphase fluid flows

2012 ◽  
Vol 9 (1) ◽  
pp. 175-180
Author(s):  
Yu.D. Chashechkin
Keyword(s):  
Large Scale ◽  
Fundamental System ◽  
Fluid Flows ◽  
Regular Solutions ◽  
Flow Models ◽  
Group Methods ◽  
Wide Range ◽  
Thin Structure ◽  
Multiphase Fluid ◽  
Complete Solutions

According to the results of visualization of streams, the existence of structures in a wide range of scales is noted: from galactic to micron. The use of a fundamental system of equations is substantiated based on the results of comparing symmetries of various flow models with the usage of theoretical group methods. Complete solutions of the system are found by the methods of the singular perturbations theory with a condition of compatibility, which determines the characteristic equation. A comparison of complete solutions with experimental data shows that regular solutions characterize large-scale components of the flow, a rich family of singular solutions describes formation of the thin media structure. Examples of calculations and observations of stratified, rotating and multiphase media are given. The requirements for the technique of an adequate experiment are discussed.

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