scholarly journals Specification of Modified Jarvis Model Parameterization for Pinus cembra

Atmosphere ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1388
Author(s):  
Anna Buchholcerová ◽  
Peter Fleischer ◽  
Dušan Štefánik ◽  
Svetlana Bičárová ◽  
Veronika Lukasová
Keyword(s):  
Stomatal Conductance ◽  
Native Species ◽  
Field Measurements ◽  
Local Environment ◽  
Coefficient Of Determination ◽  
Pinus Cembra ◽  
United Nations Economic Commission ◽  
Model Parameterization ◽  
Economic Commission ◽  
Optimal Set

The high ambient ozone concentrations cause impairing effects on vegetation leading to plant injuries. The potential ozone uptake to vegetation through open stomata can be quantified using stomatal conductance measurements under the local environmental conditions. This study compares the ozone stomatal conductance to vegetation obtained with a modified Jarvis formula adopted from the Vegetation Manual of United Nations Economic Commission for Europe, and experimental field measurements’ data. The stomatal conductance was measured by a portable photosynthesis and gas exchange analyzer system LiCOR6400. The measurements were performed in the submontane environment of the High Tatra Mountains in Slovakia on Swiss pine (Pinus cembra), as a native species of the local flora. According to previous studies, Swiss pine is considered as an ozone-sensitive species. The modified Jarvis model for the ozone stomatal conductance is compared with the field measurements. The suitable parameterization of the modified Jarvis model for Swiss pine is obtained. The parameterization of stomatal conductance for Swiss pine in the local environment would help understand its specificity and similarity to other conifer species. In the case of using parameterization for a boreal coniferous from the Vegetation Manual of the International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops, validation of the model with the measurements without temperature adjustment of the conifer chamber achieved a coefficient of determination of R2=0.75. This result is not in contradiction with the previous researches. With the optimal set of parameters, obtained in this paper, the Jarvis model reaches R2=0.85. The data suggest that Jarvis-type models with appropriate parameterization are applicable for stomatal conductance estimation for Pinus cembra when the measurements do not modify the temperature regime.

An Effective Cumulative Torsion Angles Model for Prediction of Protein Folding Rates

2020 ◽  
Vol 27 (4) ◽  
pp. 321-328 ◽  
Author(s):  
Yanru Li ◽  
Ying Zhang ◽  
Jun Lv
Keyword(s):  
Protein Folding ◽  
Size Structure ◽  
Conformational Space ◽  
Coefficient Of Determination ◽  
Folding Rate ◽  
Torsion Angles ◽  
Folding Rates ◽  
Protein Folding Rate ◽  
Optimal Set ◽  
Conformation Space

Background: Protein folding rate is mainly determined by the size of the conformational space to search, which in turn is dictated by factors such as size, structure and amino-acid sequence in a protein. It is important to integrate these factors effectively to form a more precisely description of conformation space. But there is no general paradigm to answer this question except some intuitions and empirical rules. Therefore, at the present stage, predictions of the folding rate can be improved through finding new factors, and some insights are given to the above question. Objective: Its purpose is to propose a new parameter that can describe the size of the conformational space to improve the prediction accuracy of protein folding rate. Method: Based on the optimal set of amino acids in a protein, an effective cumulative backbone torsion angles (CBTAeff) was proposed to describe the size of the conformational space. Linear regression model was used to predict protein folding rate with CBTAeff as a parameter. The degree of correlation was described by the coefficient of determination and the mean absolute error MAE between the predicted folding rates and experimental observations. Results: It achieved a high correlation (with the coefficient of determination of 0.70 and MAE of 1.88) between the logarithm of folding rates and the (CBTAeff)0.5 with experimental over 112 twoand multi-state folding proteins. Conclusion: The remarkable performance of our simplistic model demonstrates that CBTA based on optimal set was the major determinants of the conformation space of natural proteins.

scholarly journals Asymmetric Double Freeform Surface Lens for Integrated LED Automobile Headlamp

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 663
Author(s):  
Hui Zhang ◽  
Dengfei Liu ◽  
Yinwan Wei ◽  
Hong Wang
Keyword(s):  
Optical System ◽  
Design Method ◽  
Chromatic Dispersion ◽  
Electronic Devices ◽  
Color Temperature ◽  
Freeform Surface ◽  
United Nations Economic Commission ◽  
System A ◽  
Economic Commission ◽  
Key Points

We propose a design method of asymmetric double freeform surface lens for an integrated LED automobile headlamp and develop an integrated LED automobile optical system. A single asymmetric double freeform surface lens is designed to redistribute rays emitting from the light source for realizing both low and high beams. Moreover, a freeform surface reflector is used to improve the energy efficiency of high beams. The prism placed in the optical path can suppress chromatic dispersion on the edge of the target plane. Simulation and experimental results show that the illumination values and color temperature of the key points can fully meet the requirements of United Nations Economic Commission for Europe vehicle regulations (ECE) R112, 48, and 128. The volume of the whole optical system comprised of freeform surface elements is smaller than that of the low beam system of a traditional headlamp, resulting in saved space, in which other electronic devices can be installed for the safety of the driver, which indicates that the proposed method is practical in the field of automobile lighting.

scholarly journals Land surface model photosynthesis and parameter calibration for boreal sites with adaptive population importance sampler

2019 ◽  
Author(s):  
Jarmo Mäkelä ◽  
Jürgen Knauer ◽  
Mika Aurela ◽  
Andrew Black ◽  
Martin Heimann ◽  
...  
Keyword(s):  
Stomatal Conductance ◽  
Land Surface ◽  
Carbon Fixation ◽  
Gross Primary Production ◽  
Effect Of Temperature ◽  
Coefficient Of Determination ◽  
Surface Model ◽  
Drought Event ◽  
Forest Site ◽  
Delayed Effect

Abstract. We calibrated the JSBACH model with six different stomatal conductance formulations using measurements from 10 FLUXNET coniferous evergreen sites in the Boreal zone. The parameter posterior distributions were generated by adaptive population importance sampler and the optimal values by a simple stochastic optimisation algorithm. The observations used to constrain the model are evapotranspiration (ET) and gross primary production (GPP). We identified the key parameters in the calibration process. These parameters control the soil moisture stress function and the overall rate of carbon fixation. We were able to improve the coefficient of determination and the model bias with all stomatal conductance formulations. There was no clear candidate for the best stomatal conductance model, although certain versions produced better estimates depending on the examined variable (ET, GPP) and the used metric. We were also able to significantly enhance the model behaviour during a drought event in a Finnish Scots pine forest site. The JSBACH model was also modified to use a delayed effect of temperature for photosynthetic activity. This modification enabled the model to correctly time and replicate the springtime increase in GPP (and ET) for conifers throughout the measurements sites used in this study.

Haile Selassie's Imperial Modernity: Expatriate Architects and the Shaping of Addis Ababa

2016 ◽  
Vol 75 (4) ◽  
pp. 447-468 ◽  
Author(s):  
Ayala Levin
Keyword(s):  
United Nations ◽  
Addis Ababa ◽  
African Unity ◽  
United Nations Economic Commission ◽  
The Past ◽  
Economic Commission ◽  
Organization Of African Unity ◽  
The 1960S ◽  
The Individual ◽  
The City

In the 1960s, Addis Ababa experienced a construction boom, spurred by its new international stature as the seat of both the United Nations Economic Commission for Africa and the Organization of African Unity. Working closely with Emperor Haile Selassie, expatriate architects played a major role in shaping the Ethiopian capital as a symbol of an African modernity in continuity with tradition. Haile Selassie's Imperial Modernity: Expatriate Architects and the Shaping of Addis Ababa examines how a distinct Ethiopian modernity was negotiated through various borrowings from the past, including Italian colonial planning, both at the scale of the individual building and at the scale of the city. Focusing on public buildings designed by Italian Eritrean Arturo Mezzedimi, French Henri Chomette, and the partnership of Israeli Zalman Enav and Ethiopian Michael Tedros, Ayala Levin critically explores how international architects confronted the challenges of mediating Haile Selassie's vision of an imperial modernity.

The Aarhus Convention and Polish Regulations Concerning Parties to Proceedings for Issuing the eia Decisions

2021 ◽  
Vol 18 (1-2) ◽  
pp. 56-76
Author(s):  
Magdalena Michalak ◽  
Przemysław Kledzik
Keyword(s):  
Environmental Law ◽  
Legal Order ◽  
Access To Justice ◽  
United Nations Economic Commission ◽  
The Public ◽  
Law And Policy ◽  
Economic Commission ◽  
Aarhus Convention ◽  
Key Issues ◽  
Environmental Law And Policy

Abstract The United Nations Economic Commission for Europe Convention on Access to Information, Public Participation in Decision-Making and Access to Justice in Environmental Matters was adopted on 25 June 1998 in the Danish city of Aarhus. According to its provisions each state Part shall, within the framework of the national legal order, ensure that members of the public concerned have access to a review procedure before a court of law or another independent and impartial body established by law. At the same time, it contains regulations specifying the criteria that constitute the basis for determining persons enjoying rights to access justice with respect to national legal orders. Poland, being one of the state Parties, introduced into national legal order special provisions enabling implementation of the Aarhus Convention, including regulations concerning parties to proceedings in environmental matters. The aim of the study is to analyse and assess these regulations in the light of the requirements adopted in the Aarhus Convention and to formulate general conclusions in the field of key issues of the international and European environmental law and policy.

The UN Economic Commission for Latin America (CEPAL) and the Development Project

2021 ◽  
Author(s):  
Margarita Fajardo
Keyword(s):  
Economic Development ◽  
Latin America ◽  
World War Ii ◽  
International Development ◽  
Global Economy ◽  
Raw Materials ◽  
New Left ◽  
Development Project ◽  
United Nations Economic Commission ◽  
Economic Commission

The United Nations Economic Commission for Latin America (ECLA in English and CEPAL in Spanish and Portuguese) was more than an economic development institution. Established in 1948, at the height of post-World War II internationalism, CEPAL was one of the first three regional commissions alongside those of Europe and Asia charged with addressing problems of postwar economic reconstruction. But, in the hands of a group of mostly Argentinean, Brazilian, and Chilean economists, CEPAL swiftly became the institutional fulcrum of a regional intellectual project that put Latin America at the center of discussions about international development and global capitalism. That Latin America’s place in the periphery of the global economy as a producer of primary products and raw materials in exchange for manufactured goods from the world’s industrial centers, combined with the long-term decline in the international terms of that trade, constituted an obstacle for economic development, was the foundational tenet of that project. Through regional economic surveys and in-depth country studies, international forums and training courses, international cooperation initiatives, and national structural reforms, cepalinos located themselves at the nexus of a transnational network of diplomats and policymakers, economists and sociologists, and made the notion of center–periphery and the intellectual repertoire it inspired the central economic paradigm of the region in the postwar era. Eclipsed in the 1970s by critiques from the New Left and dependency theorists, on the one hand, and by the authoritarian right and neoliberal proponents, on the other hand, the cepalino project remains Latin America’s most important contribution to debates about capitalism and globalization, while the institution, after it reinvented itself at the turn of the century, still constitutes a point of reference and a privileged repository of information about the region.

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