bluuebunny/crossref_metadata_2025 huggingface dataset:
The soil mite Cunaxa capreolus (Acari: Cunaxidae) as a predator of the root-knot nematode, Meloidogyne incognita and the citrus Nematode, Tylenchulus semipenetrans: Implications for biological control
Authors: Al-Azzazy Mahmoud M. , Al-Rehiayani Suloiman M.
Published: February 2022

Plant-parasitic nematodes (PPNs) are dangerous pests, causing serious losses to the world’s agricultural crops. As soil-dwelling predaceous mites are known as potential biological control agents against many pests, we investigated the interactions between the cunaxid mite, Cunaxa capreolus (Berlese), and two plant parasites (root-knot nematode, Meloidogyne incognita (Kofoid and White) and the citrus Nematode, Tylenchulus semipenetrans Cobb under laboratory conditions. The predatory mite C. capreolus completed its life-span when fed on egg masses EM and second-stage juveniles J2 of M. incognita and J2 juveniles of T. semipenetrans as food sources in the laboratory in sealed arenas at 32ºC, 60% relative humidity in the dark. Males developed slightly faster than females irrespective of different prey. Adult females lived longer than males and showed a higher rate of food consumption. Life table parameters indicated that feeding C. capreolus on J2 juveniles of M. incognita and J2 juveniles of T. semipenetrans led to the highest reproduction rate (rm= 0.185 and 0.167 females/female/day), while feeding on EM of M. incognita gave the lowest reproduction rate (rm= 0.085). The results show that C. capreolus multiplied rapidly when juveniles of M. incognita and T. semipenetrans were offered as prey, indicating the mite’s potential for regulating population densities of these two pests. Future research should focus on understanding the crop and soil management applications required to enable this cunaxid mite and other predatory species to thrive. The implications of these results on biological control of plant parasitic nematodes are discussed.
Serum cobalamin concentrations in dogs infected with canine parvoviral enteritis
Authors: Engelbrecht Monique , Botha Willem Jacobus , Pazzi Paolo , McClure Vanessa , Hooijberg Emma
Published: February 2022

OBJECTIVE

To compare the serum cobalamin concentrations in canine parvovirus (CPV)–infected dogs with those of healthy control dogs.

Animals

45 dogs with CPV enteritis and 17 healthy age-matched control dogs.

Procedures

Infection was confirmed by visualization of CPV-2 through fecal electron microscopy. All dogs received supportive care. Serum samples taken at admission were used to determine cobalamin, C-reactive protein, and albumin concentrations.

Results

Serum cobalamin concentrations were significantly lower in the CPV-infected group (median [interquartile range], 173 pmol/L [< 111 to 722 pmol/L]) than in healthy control dogs (379 pmol/L [193 to > 738 pmol/L). There was no association between cobalamin concentration and C-reactive protein or albumin concentration.

Clinical Relevance

While hypocobalaminemia was common in CPV-infected dogs, the clinical relevance of this finding remains to be determined. Studies assessing markers of cellular cobalamin deficiency in dogs with CPV infection appear warranted.
Public Service Media in the Age of Social Networks
Authors: Glózer Rita
Published: February 2022

Digital transformation and the expansion of social networks have essentially modified journalistic practice, facing challenges concerning its essential operation and boundaries. The traditional business models have collapsed, young people’s media consumption habits have changed, and more non-professional journalists participate in news production. Social media platforms have an immense effect on journalistic work, especially journalists’ professional and ethical standards. Perhaps traditional public service media are the ones that stand the farthest away from participatory practices and platform logic, characterizing today’s media environment. What are the public media services’ opportunities to fulfil their commitment of authentically and objectively informing citizens, including young people, about public affairs? This study aims to picture the boundary work of journalism currently underway by reviewing the phenomena emerging on the border of journalism and social media. Additionally, the study attempts to answer what a successful social media strategy looks like in public service media by presenting the social media activities of “tagesschau”, the newsmagazine of ARD, a German public-service channel.
New Digital Cinema: How Platforms Are Changing the Audiovisual Industry
Authors: Capalbi Antonella , Fabbri Tommaso , Iervese Vittorio
Published: February 2022

Digitalization has been changing the methods of production, distribution, and use of written and audiovisual products, according to a process of “platforming”. Most audiovisual content is available via streaming platforms, through a lot of devices (PCs, tablets, smartphones, smart TVs, and videogame consoles), which have empowered the process of media convergence. Based on a theoretical framework related to the impact of the platforms on the ongoing process, we intend to analyse how platforms are changing the identity of the audiovisual industry and how they represent themselves online. In order to analyse the ongoing process, we intend to examine some platforms that could be considered as best practices in the audiovisual field: Netflix, MUBI, and Festival Scope. On the one hand, using these platforms as case studies will enable us to highlight some beneficial aspects of the ongoing process of digitalization and platforming: holding many gazes and points of view; catching market niches; building a peer-to-peer network. On the other hand, we intend to emphasize some risks connected to the intermediation of platforms in the audiovisual field in terms of economic, cultural, and social effects.
Beyond Netiquette: Digital Citizenship as Participation
Authors: Bakó Rozália Klára
Published: February 2022

Digital citizenship research has been on the agenda of scholars and practitioners since 1999 and has been trending since 2015. A plethora of approaches and definitions have been arising, with two major directions: a theoretical-methodological and a practical-educative. The present critical literature review is aimed at advocating for a more civic approach to the issue of digital citizenship and at presenting arguments in favour of a research agenda focused on the participatory components of digital life. Our desk research operated with both original studies and meta-analyses related to the concept of digital citizenship. While being technically savvy and well-behaved online is a key requirement for today’s netizen, becoming a citizen in virtual spaces requires more. Beyond netiquette, civic participation online is becoming a core competence.
Online Identities in Politics. Technological and Content-Based Approach
Authors: Szűts Zoltán
Published: February 2022

In this study, we examine a particular form of organizational identity, the issue of political organizational identity. We have chosen a technology and content-based approach and are looking for the answer to how technology influences identity formation, what role social media plays in shaping online political communities, and what characterizes a definable and strong online political identity. The impact of new communication technologies and media platforms has now reached all levels of society. It has influenced many aspects of everyday life, transformed politics, the economy, and culture, and has an impact on institutional identities as well. To identify the forces shaping institutional identity, we examine the role of digitalization, network technologies, and algorithms and the presence of social media and, finally, bring the Occupy Wall Street movement as an example of reshaping online identities.
Value added in sawmilling industry in the Czech Republic
Authors: Palátová Petra
Published: February 2022

The paper deals with sawmilling and timber processing capacities in the territory of the Czech Republic. Selected operations are sawmills with the annual processing capacity over 10,000 m3, further divided into groups by the annual volume of processed raw material. In total 35 companies, which were chosen at random, were compared based on the indicator of value added per employee. The results show that the value added considerably differed not only among the groups but also within the individual groups of sawmill establishments.
Tree-ring widths as an indicator of air pollution stress and climate conditions in different Norway spruce forest stands in the Krkonoše Mts.
Authors: Putalová Tereza , Vacek Zdeněk , Vacek Stanislav , Štefančík Igor , Bulušek Daniel , Král Jan
Published: February 2022

The negative effect of air pollution on mountain spruce stands culminated in the 70s – 90s of the 20th century, when an extensive dieback and disturbance of stands occurred in the Krkonoše Mts., the Czech Republic. Dendrochronological analysis was used on ten permanent research plots established in 1976–1980 to document the dynamics of radial increment of Norway spruce (Picea abies [L.] Karst.). The objective was to determine the effect of SO2, NOX and O3 concentrations and precipitation and temperatures on spruce radial growth in climax forests, waterlogged forests and cultivated forests. The results document the strong depression of diameter increment in the period 1979–1991 caused by synergism of climatic extremes and high SO2 pollution in the 80s and 90s of the 20th century. After 2000 climate had prevailing effect on radial growth. Spruce increment was in positive correlation with temperature, particularly with temperature in the growing season and annual temperature of the current year. In general, temperature had a more significant effect on increment than precipitation, mainly in climax and peaty spruce stands. Diameter increment was in significant negative correlation with SO2 and NOX concentrations in all types of stands. Overall, peaty spruce stands were the most vulnerable to air pollution stress. Low radial increments were caused also by climate extremes, historically by strong frosts and winter desiccation in early spring, nowadays in time of climatic changes by extreme drought. Spruce stands have the ability of quickly responding by tree-ring width to both negative and positive impulses related with air pollution and climate.
Determining the Response Over Time, Current Amplification, Input and Output Resistance of a Parallel-Series Amplifier
Authors: Puchianu D.C.
Published: February 2022

The study determines the behavior type of the parallel-series amplifier and determines the amplification of the basic amplifier, the input and output resistance, as well as the amplification of the reaction network and the input and output resistance of the reaction network. With the help of the negative reaction, the designer can change the properties of the amplifier. Thus, a dynamic, automatic stability of the amplification system is obtained.
Battery Management System for an Electric Vehicle
Authors: Issa F.
Published: February 2022

In the electric vehicle industry, a battery management system is needed when voltages are in the value of hundreds of volts. The battery management system is not only used to estimate the remaining capacity of the batteries but also to prevent various hazards that may occur in case of improper use. The paper offers a review of the battery management system that is used in the modern electric vehicles. The system is described along with its functions including the practical methods for balancing the battery and the type of batteries used in the automotive industry.
Home Automation System Using ESP8266 Microcontroller and Blynk Application
Authors: Visan I. , Diaconu E.M.
Published: February 2022

This paper proposes the creation of a home automation system using an ESP8266 microcontroller and the Blynk application. The system consists of 2 sensors responsible for measuring the temperature/humidity and the level of brightness in the building, a 4-channel relay module responsible for controlling 4 devices/appliances/electrical installations and an LED that demonstrates its control through a PWM signal provided by the ESP8266 microcontroller. Using the Blynk application this system can be controlled and monitored via a Wi-Fi connection directly on the mobile device which makes this system an IoT (Internet of Things) one. The programming of the system was done in the Arduino IDE program using the already existing libraries for the sensors and for the Blynk application. The mobile application used for controlling and monitoring the system is able to display information about temperature /humidity, brightness and on the control side, the application allows the user to individually operate each channel of the relay module and the LED.
Phytochemical and Pharmacological Properties of Allium Ursinum
Authors: Krivokapic Milos , Bradic Jovana , Petkovic Anica , Popovic Marina
Published: February 2022

Allium ursinum L. is a perennial herbaceous plant belonging to the Alliaceae family. Several classes of bioactive compounds have been isolated from A. ursinum so far, among them sulfur and phenolic compounds as quantitatively the most distributed constituents, responsible for pharmaceutical eff ects of the plant. Small amounts of steroidal glucosides, lecitins, fatty acids and several amino acids, as well as the essential oil are also present in A. ursinum. This plant species is characterized by a long history of use in traditional medicine in the prevention and treatment of cardiovascular disease, as digestive stimulant, antimicrobial agent, as a remedy in respiratory problems, insomnia and fainting. Despite its widespread use for medicinal purposes since the ancient time, studies referring to its pharmacological activity are still lacking. In this review, we summarized the current knowledge related to the phytochemical and pharmacological properties of Allium ursinum. This study may be a starting point for future researches in this field, which would fully clarify therapeutic potential of A. ursinum and make it a possible candidate for medicinal product.
What the Right to Eduation Is, and What It Ought to Be: Towards a Social Ontology of Eduction as a Human Right
Authors:   , Norefalk Christian
Published: February 2022

During the second half of the 20th century education has been recognized as a human right in several international conventions, and the UN also holds that “Education shall be free” and that “Elementary education shall be compulsory” (UN, 1948, Article 26). The education-as-a-human right-project could be viewed as a good intention of global inclusion in recognizing that all individuals have a right to education in virtue of being humans, and the idea of education as a human right thus has a tremendous global significance. However, if we look at this more critically, the education-as-a-human right-project, may not only be grounded in altruistic good intensions for the disadvantaged. The term “elementary education”, or sometimes “primary education”, which is used in several human rights-documents seems to suggest that it is some sort of formalized education. It would be useful however to make a distinction between formal and informal education, as well as between teaching, learning, education and schooling, in the discussion of the right to education and specifically in the discussion concerning education as a “human right”. There is obviously a difference between the right to teach, the right to learn, the right to education and the right to schooling. And how are these rights related to compulsory schooling, compulsory education and the supposed duty to teach and duty to learn? A further concern is what makes this a human right rather than for example a juridical right as a citizen. By addressing these questions within a theoretical framework of social ontology and ameliorative conceptual analysis I believe that we can find new ways of dealing with fundamental problems within philosophy of education such as the nature, purpose and aims of education as well as the right to education.
Waste-Cooking-Oil Free Fatty Acid Reduction Using Deep Eutectic Solvent as Raw Material of Biodiesel
Authors:   Applied Master of Renewable Energy Engineering, Politeknik Negeri Sriwijaya, Jl. Srijaya Negara, Bukit Besar, Ilir Barat I, Palembang, Putri Mutiara , Kalsum Leila , Syarif Aida
Published: February 2022

The purpose of this study was to extract the free fatty acid (FFA) of waste-cooking-oil through liquid-to-liquid extraction using choline chloride as a raw material for Deep Eutectic Solvent (DES) as a waste-cooking-oil purifier. Waste-cooking-oil is obtained from the waste of a fast food factory located in Sukarame, South Sumatera. Making a Dep Eutectic Solvent (DES) using compounds of ethylene glycol as Hydrogen Bond Donor mixed with a choline chloride Hydrogen Bond Acceptor with five molar ratios, a reaction temperature of 60 °C and a stirring speed of 150 rpm and 200 rpm for 90 minutes. The extraction molar ratio of waste-cooking-oil and DES with four ratios of molar ratios, extraction time of 2 hours at 60 °C and retention time of separation between DES and used cooking oil was 24 hours. The decrease in FFA of waste-cooking-oil was the highest at 83.87% in the DES 2. It proves that DES is able to purify waste-cooking-oil by extraction methods to reduce FFA and adsorb other materials
The Optimum Yield of Nannochloropsis sp Microalgae from the Lipid Cultivation and Extraction Process with Soxhlet Method
Authors:   Applied Master of Renewable Energy Engineering, Politeknik Negeri Sriwijaya, Palembang, Hakim Lukmanul , Rusdianasari Rusdianasari
Published: February 2022

The new renewable energy source, namely microalgae biomass, which is the third generation in its utilization derivative, has a lipid content productivity that has great potential to be used as raw material for biodiesel production. One species of microalgae, Nannochloropsis sp., is ideal for cultivation and has a higher photosynthetic efficiency than land plants. Methods to obtain microalgae oil from dry raw materials can be carried out from several processes, but the most effective and easy method is extraction with solvents using a Soxhlet device. The purpose of this study was to determine the optimal growth of Nannochloropsis sp microalgae cell density observations in the cultivation process and to see the percent yield of lipids from microalgae Nannochloropsis sp. through the extraction process with the Soxhlet method using n-hexane and ethanol solvents at a ratio of 1:1, 1:2, 1:3, 1:4 and 1:5. The optimal amount of cell density during the cultivation process has obtained an average of 32.206 x 104 cells/ml on day of 9th, and the optimal lipid yield was in the ratio of hexane: ethanol 1:1 with a value of 32.13%. These results show that the optimal conditions for yield can be obtained and also has the potential as a raw material biodiesel production
Implementasi Pengelolaan Alokasi Dana Desa pada Masa Pandemi Covid-19
Authors: Hartati Sandra , Fathah Rigel Nurul
Published: February 2022

This study aims to analyze the management of village fund allocation and the effectiveness of financial performance in South Pringgasela Village which has received budget reductions during the Covid-19 pandemic.  This study employs descriptive qualitative methods through interviews, observation and documentation. The results show that the management of village fund allocation in South Pringgasela Village technically and administratively has been carried out well based on the timeliness of disbursement of village funds allocation, and the effectiveness level of financial performance by 92% indicates that the financial performance is effective based on the achievement of goals, timeliness, suitability benefits, and expectations of society.
Systems approach to modeling recycling refrigeration machines
Authors:   Kerch State Marine Technological University, Kerch, Russia, Bogatyreva E.V.
Published: February 2022

Refrigeration equipment is not provided on many small fishing vessel projects. It is proposed to install absorption refrigerating machines (ABRM) as refrigeration units for small vessels of the fishing fleet, the working medium of which is a water ammonia mixture. Such machines can operate by using the heat of exhaust gases, that is, receive energy from internal combustion engines. Ship power plants, unlike stationary ones, have characteristics and properties inherent only to them. In modeling, it is proposed to use a systematic approach to optimize the parameters. The principle of a systematic approach is considered. An example of dividing ABRM into subsystems is given. The graph of the simplified thermal circuit of ABRM is presented. Recommendations are given for optimizing the operating parameters.
Is there a future for sails
Authors:   St. Petersburg State Marine Technical University, St. Petersburg, Russia, Burlaka K.A. , Zubov N.N. ,   St. Petersburg State Marine Technical University, St. Petersburg, Russia, Rogozin A.V. ,   St. Petersburg State Marine Technical University, St. Petersburg, Russia
Published: February 2022

Using wind power to reduce the concentration of carbon dioxide emissions into the atmosphere. That will save the planet from pollution in the future.
Modeling the processes of fuel supply during the operation of marine diesel engine using water-fuel emulsion
Authors:   St. Petersburg State Marine Technical University, St. Petersburg, Russia, Chistyakov A.Yu. , Gorelik G.B. ,   Pacific State University, Khabarovsk, Russia, Mozolev O.N. ,   Pacific State University, Khabarovsk, Russia
Published: February 2022

The article presents the results of the mathematical modeling of marine diesel’s fuel supply processes during the screw characteristic while using diesel fuel and water-fuel emulsion with 30% water content as alternative fuel. As a result of the research, the features of the fuel supply processes and the effect of alternative fuel on the serial fuel equipment injection characteristics during operation in nominal and partial modes were identified. Considering the quality of fuel equipment operation the following features were taken into account, they are: changing fuel supply characteristics; features of fuel atomization in the initial and final phases of injection; increasing stability of the injection in sequential cycles by increasing plunger active stroke; residual pressure oscillations in the high pressure line during injection consecutive cycles. Using the water-fuel emulsion it is possible to significantly increase a quality of marine diesel engine operation, to extend the stable fuel supply range of the serial fuel equipment both from the possibility of speed modes reducing during fine fuel feed and providing forced fuel feed due to absence of repeating injections.
Dynamics and Response to Control of Single and Dual Supersonic Impinging Jets
Authors: Song MyungJun , Bhargav Vikas N. , Seçkin Serdar , Sellappan Prabu , Kumar Rajan , Alvi Farrukh S.
Published: February 2022

An impinging jet produces a highly unsteady flowfield which results in very high noise levels, harmful structural vibrations, and significant loss of lift and stability in applications such as the short takeoff and vertical landing aircraft. An understanding of the flowfield and implementation of an effective flow control technique are necessary to reduce these adverse effects. The presence of multiple impinging jets leads to the generation of a fountain flow, which further adds to the complexity of the flowfield dynamics. In the present study, flowfields of a single supersonic round jet (Mach 1.5) and dual impinging jets (consisting of a Mach 1.5 supersonic jet and an additional sonic jet) are explored. A microjet-based control method is applied to attenuate flow unsteadiness by modifying shear layer instability characteristics of the supersonic jet. Passive and active influence of the microjet hardware on acoustics are examined over a range of impingement distances (2.25D–10D) with a fine resolution (D/16) to obtain detailed resonance characteristics. Based on the resonance tone behavior as a function of impingement distances, detailed flowfield characteristics at certain impingement distances are investigated with the help of schlieren visualization, near-field acoustics, and unsteady surface pressure measurements. The effectiveness of the microjet flow control method in reducing noise is also evaluated in the flowfield of single and dual impinging jets. For single and dual impinging jets configuration, relative to their respective baseline cases, the microjet control on dual impinging jets shows better noise attenuation of overall sound pressure level within short impingement distances ([Formula: see text]).
Prosopographie et biographie : regards croisés sur la magistrature coloniale belge
Authors: Ngongo Enika , Piret Bérengère , Montel Laurence , le Polain de Waroux Pascaline
Published: February 2022

L’article présente l’avancement et les perspectives du projet « Belgafrima : prosopographie des magistrats coloniaux » (Belgafrican Magistrates) qui élargit au terrain ultramarin la prosopographie des magistrats belges et l’établissement de la carte judiciaire. Le but étant d’entreprendre, à partir des données biographiques saisies, une étude du corps judiciaire colonial. Celle-ci doit mettre en évidence les carrières et réseaux de ces membres tout en prêtant attention aux contraintes collectives comme aux stratégies individuelles. Il est d’abord fait retour sur les sources de cette recherche et sur les difficultés techniques que cette extension du sujet a posées à une base de données pensée à l’origine pour la magistrature métropolitaine. En contrepoint de cette analyse prosopographique, le présent article s’attache également à mettre en exergue le parcours d’Antoine Sohier, membre éminent de la magistrature coloniale.
From barracks to brothels : prostitution’s regulation for the benefit of the military institution (1900-1939)
Authors: Duffuler-Vialle Hélène
Published: February 2022

De la Révolution à 1946, la France est réglementariste, c’est-à-dire que la prostitution, pensée comme un mal nécessaire, est régulée par des réglementations locales, harmonisées par des injonctions ministérielles. Si en général les clients de la prostitution ne font l’objet d’aucun traitement spécifique par l’autorité régulatrice, la clientèle militaire constitue une exception. En effet certaines dispositions réglementaires les concernent. Cette clientèle est considérée comme particulièrement vulnérable dans un contexte de « Nation en danger » où la syphilis représente un péril national. A la fin du XIXe siècle et jusqu’en 1916, une politique d’éducation sexuelle préventive est mise en place auprès des soldats, où la chasteté est prônée comme la meilleure garantie. De manière pragmatique, la maison de tolérance reste considérée comme le meilleur moyen de contrôler la sexualité des soldats et d’éviter qu’ils ne contractent des maladies vénériennes. Ainsi, d’une part, l’institution militaire lutte contre la prostitution clandestine et d’autre part fait obstacle à la mise en place du système abolitionniste ou semi-abolitionniste dans les quelques villes qui tentent de l’installer. Le réglementarisme est adapté aux nécessités militaires et, à partir de 1916, il n’est plus question de revoir le système mais de renforcer son efficacité prophylactique. Dans ce contexte l’autorité militaire est ponctuellement saisie de questions juridiques particulières : existe-t-il un droit d’accès aux maisons de tolérance pour les militaires ? Les femmes qui se prostituent ont-elles le droit de refuser des clients ? Quid de la discrimination raciale ?
Frequently recorded sensor data may correctly provide health status of cows if data are handled carefully and errors are filtered away
Authors: Løvendahl Peter , Sørensen Lars Peter
Published: February 2022

Description of the subject. The implementation of sensor based decision support in commercial dairy herds is highly dependent on having reliable systems. Problems with sensors give missing and noisy data hampering their use. Also, the presentation of results needs to be in a form which is simple and useful. These issues were addressed using a mastitis sensor and decision support as example. Objectives. This study aims at providing and evaluating a modular system applicable to the pipeline from sensor to decision support. Method. The case of mastitis was chosen as it is of economic importance and also affects welfare of cows, and because we have worked with a commercial sensor. The problems with sensors causing missing data and noise are described and a range of filtering and monitoring modules are shown to be important to make systems functional for herd management purposes. On top of this a solid method needs to be used to interpret and present data to end users, in terms of easy to read categories. Results. Filtering and pre-adjustments of raw data are important in making algorithms robust and reliable for daily use. Re-definition of traits is needed going from traditional few groups to continuous definitions, and then to new action oriented health classes. Also, for this case focusing on mastitis, assignment to “permanently sick” groups can be helpful in keeping focus on new acute cases. Conclusions. The combined use of filtering, fix-up routines and time series models leading into action oriented categories is needed to provide simple and robust decision support. The systems may be vastly improved by opening for transmission of data between user groups and to common databases – also with a few to use data in genetic selection.
Mesure des flux de CO2 et séquestration de carbone dans les écosystèmes terrestres ouest-africains (synthèse bibliographique)
Authors: Ago Expedit Evariste , Agbossou Euloge Kossi , Ozer Pierre , Aubinet Marc
Published: February 2022

Introduction. En Afrique de l’Ouest comme ailleurs dans d’autres régions du monde, la préservation des écosystèmes terrestres s’avère primordiale pour toute politique d’atténuation des émissions de gaz à effet de serre, en particulier du dioxyde de carbone. Une évaluation pertinente de la contribution d’une région donnée au cycle global du carbone implique la nécessité de raisonner en termes de bilan en considérant dans l’analyse tous les flux d’exportation et d’importation dans les écosystèmes. Littérature. Une synthèse bibliographique, basée sur les résultats publiés ou non de quelques études ayant porté sur les écosystèmes ouest-africains, a été conduite avec pour objectif principal d’évaluer l’importance des échanges de carbone avec l’atmosphère. Il ressort que les flux de carbone présentent une importante variabilité spatiale, principalement liée à la variabilité des conditions pédo-climatiques, des modes de gestion, des types de végétation et des formes d’usage des écosystèmes. La pluviométrie moyenne annuelle apparait être le facteur principal contrôlant les échanges de carbone dans la région. La variabilité spatiale de la photosynthèse explique 71 % de celle de cumuls annuels de NEE. Cet article confirme le comportement de puits de carbone de l’ensemble des écosystèmes terrestres ouest-africains considérés avec une séquestration moyenne annuelle de -2,0 ± 1,5 t C·ha-1 et fait apparaitre la nécessité d’améliorer la compréhension des mécanismes ou des facteurs qui contrôlent les échanges de carbone entre les écosystèmes et l’atmosphère. Conclusions. Considérant les résultats de quelques sites, il apparait nécessaire de poursuivre les mesures des flux de carbone à l’échelle de l’écosystème sur le long terme afin de mieux apprécier leurs variabilités spatio-temporelles, notamment saisonnières et inter-annuelles. Cet article met également en évidence la nécessité d’étendre les mesures d’eddy covariance dans la région et à d’autres types de végétation de manière à faciliter des études de comparaison entre différents types d’écosystème. Ces études permettront de suggérer des modes de gestion plus durables favorisant la séquestration de carbone tout en limitant les émissions.
Sources de revenus et besoins d’accompagnement des exploitations agricoles familiales en zone cotonnière ouest du Burkina Faso
Authors: Koutou Mahamoudou , Sangaré Mamadou , Havard Michel , Toillier Aurélie , Sanogo Lacina , Thombiano Taladidia , Vodouhe Davo Simplice
Published: February 2022

Description du sujet. Dans la zone cotonnière ouest du Burkina Faso, la variabilité et la diversité des revenus des exploitations agricoles familiales (EAF) demandent pour ces dernières des accompagnements appropriés. Objectifs. Cet article rend compte de cette diversité et des besoins d’accompagnement selon les types d’EAF identifiés. Méthode. Les données ont été collectées par la méthode active de recherche participative et par enquête auprès d’un échantillon raisonné de 120 exploitations dans la commune de Koumbia. Une analyse en composante principale avec des indicateurs économiques de l’EAF suivie d’une classification ascendante hiérarchique ont été appliquées. Les caractéristiques structurelles, les pratiques de production agro-pastorales, les perceptions des chefs d’EAF sur les contraintes et opportunités de production agropastorale ont été comparées par une analyse de variance. Résultats. Les résultats montrent trois types d’exploitations : les exploitations à faible revenu culture (agriculteurs), à fort revenu culture (agro-éleveurs) et à revenu élevage (éleveurs). À la lumière de leurs structures, pratiques de production, performances technico-économiques et opportunités de production agricole, leur accompagnement peut porter sur plusieurs innovations durables communes ou spécifiques des types identifiés. Des accompagnements sur la gestion des ressources de l’exploitation, les bonnes pratiques de gestion de la fertilité des sols et des animaux sont communs aux trois types d’EAF. Les cultures fourragères, l’embouche et la production laitière sont spécifiques aux agro-éleveurs et éleveurs. L’amélioration de la valeur nutritive des résidus de cultures et l’entretien des bœufs de trait conviennent plus aux agriculteurs. Conclusions. Pour réussir, le processus d’accompagnement doit prendre en compte ces spécificités et la notion de durabilité.
Impact of climatic factors on the release of E-β-caryophyllene from alginate beads
Authors: Daems Frédéric , Béra François , Lorge Stéphanie , Fischer Christophe , Brostaux Yves , Francis Frédéric , Lognay Georges , Heuskin Stéphanie
Published: February 2022

Description of the subject. Alginate beads that release semiochemical compounds are interesting biological control devices used to attract the natural enemies of aphids in infested crops. Little information, however, is available about the impact of climatic factors on the release of semiochemicals from this diffusive system. Objectives. The objective of this scoping study was to investigate the impact of temperature, relative humidity and wind speed, on the release of E-β-caryophyllene from alginate beads. Method. The impact of the three climatic factors on the release of E-β-caryophyllene from alginate beads was evaluated using a Box-Behnken experimental design and a laboratory scale volatile collection system. The influence of relative humidity on bead water content and size, with and without this semiochemical, was also investigated using a gravimetric method and an easy-to-use photographic device, respectively. Results. The results showed that an increase in temperature caused a significant increase in the E-β-caryophyllene release rate. Neither relative humidity nor airflow, however, had a significant effect on the release of this semiochemical when relative humidity and wind speed ranged from 33% to 75% and from 6.61 x 10-4 m·s-1 to 2.05 x 10-2 m·s-1, respectively. The isotherm curves obtained were characteristic of food products and biopolymer materials. The isotherm shapes were not modified by the incorporation of the semiochemical into alginate beads, and showed an important increase in water content when relative humidity values exceeded 85%. Fortunately, this water content increase did not affect bead size, which facilitates the calculation of E-β-caryophyllene release. Conclusions. The present study shows for the first time the impact of the three main climatic factors on the release of E-β-caryophyllene from alginate beads. It allows learning more about how these biological control devices operate in order to optimize future field trials.
Sphingolipids: promising lipid-class molecules with potential applications for industry. A review
Authors: Miazek Krystian , Lebecque Simon , Hamaidia Malik , Paul Aman , Danthine Sabine , Willems Luc , Frédérich Michel , Pauw Edwin De , Deleu Magali , Richel Aurore , Goffin Dorothée
Published: February 2022

Introduction. Sphingolipids are a group of lipid molecules, the focus on which has been gradually increasing during recent years. This review presents sphingolipids, as valuable compounds with a high potential for industry. Literature. Structures of sphingolipids are described and their natural sources are presented. Different methods for extraction, purification and structural characterization of sphingolipids are evaluated. Activity of sphingolipids towards various microorganisms is discussed and methods for chemical modifications of natural sphingolipids to obtain novel properties are depicted. Finally, applications for implementing sphingolipid molecules in food, cosmetic, pharmaceutical or medical industry are proposed. Conclusions. Sphingolipids are molecules of high impact and their importance will inevitably increase in the future.
Agronomic assessment of spent substrates for mushroom cultivation
Authors: Picornell-Buendía Raquel , Pardo-Giménez Arturo , Juan-Valero José Arturo de
Published: February 2022

Description of the subject. In this work the agronomic viability of substrates based on spent Agaricus bisporus Imbach (Lange) substrates (SAS) and spent Pleurotus ostreatus (Jacq.) P. Kumm. substrates (SPS) is studied. Objectives. The aim of this work is the qualitative agronomic evaluation of SPS and SAS and the mixture of thereof in different proportions, such as lignocellulosic sources in new growing cycles of P. ostreatus. Method. In addition to the commercial substrate used as a control reference, six different treatments are considered. In this experiment, SPS and SAS were mixed in different amounts. SAS was subjected to a heat treatment in a growing room (“cook out”) and then to a maturation treatment which consisted of a controlled recomposting process in cameras. SPS was subjected to a pasteurizing heat treatment (60 °C – 65 °C, 8 h) and a progressive temperature decrease for at least 15 h to a “seeding” temperature (25 °C). Results. SPS (3,600 g) + SAS (2,400 g) and SPS (3,000 g) + SAS (3,000 g) were prepared substrates that achieved acceptable crude protein content in their fruiting bodies. Additionally, we obtained higher ash content, lightness, yellow-blue (y-b) and red-green (r-g) chromaticity, breaking strength (Bs), and compression energy (CE) in these mushrooms. These values were higher than the mean values, and even higher than the commercial substrate. Conclusions. Increased SAS participation in the mixture of the processed substrate (and the consequent reduction of SPS participation) resulted in mushrooms that require higher Bs, and CE. These formulation-based composts degraded by the growth of P. ostreatus, could be a low-cost substrate with selective and balanced nutrients for growth and development of oyster mushrooms.
Biomasse et stocks de carbone des forêts tropicales africaines (synthèse bibliographique)
Authors: Panzou Grace Jopaul Loubota , Doucet Jean-Louis , Loumeto Jean-Joël , Biwole Achille , Bauwens Sébastien , Fayolle Adeline
Published: February 2022

Introduction. Quantifier les stocks de biomasse et de carbone contenus dans les forêts tropicales est devenu une priorité internationale dans le cadre de la mise en œuvre du mécanisme REDD+. La biomasse forestière est estimée à trois échelles spatiales successives : l’arbre, le peuplement et la région. Cet article propose une synthèse des connaissances sur l’estimation de la biomasse et des stocks de carbone contenus dans les forêts tropicales africaines. Littérature. Cette synthèse bibliographique démontre que peu d’équations allométriques, équations qui permettent d’estimer la biomasse de l’arbre à partir de mesures non destructives (diamètre, hauteur), ont été établies pour les forêts tropicales africaines. Au niveau du peuplement, cette synthèse met en exergue les variations spatiales et temporelles connues de la biomasse entre les types de forêts d’Afrique tropicale. Si la reconstitution de la biomasse après une perturbation (l’exploitation forestière, par exemple) est relativement rapide, il existe encore beaucoup d’incertitudes sur les variations spatiales de la biomasse et il n’y a pas de consensus sur une cartographie régionale de la biomasse. La qualité de la cartographie de la biomasse dépend fortement des différents capteurs utilisés (optique, RADAR ou LiDAR) et de l’équation allométrique utilisée pour convertir les données d’inventaires forestiers en biomasse. Conclusions. Considérant le manque de précision des équations allométriques disponibles et des données d’inventaires forestiers à large échelle spatiale, il y a encore beaucoup d’incertitudes sur les estimations de la biomasse et des stocks de carbone contenus dans les forêts tropicales africaines.
Evaluation of the allelopathic potential of water-soluble compounds of barley (Hordeum vulgare L. subsp. vulgare) and great brome (Bromus diandrus Roth.) using a modified bioassay
Authors: Bouhaouel Imen , Gfeller Aurélie , Fauconnier Marie-Laure , Delory Benjamin , Amara Hajer Slim , Jardin Patrick du
Published: February 2022

Description of the subject. The present study focuses on the description of the allelopathic interactions between wild and crop species that may occur in a given ecosystem. Objectives. The objective is the evaluation of the allo- and autoinhibition activity of root exudates of barley (Hordeum vulgare L. subsp. vulgare) and great brome (Bromus diandrus Roth.) seedlings by water-soluble allelochemicals. Method. The allelopathic activities of five Tunisian barley genotypes (modern varieties and landraces), one Saudi Arabian barley landrace and great brome were assessed using a modified laboratory bioassay named “seedling-after-seedling agar method”. Results. The barley or the great brome reduced, to a greater extent, the root growth compared to the shoot growth of receiver species. The response of the root system architecture of the great brome towards barley root exudates was studied in detail. All the measured root traits were highly sensitive to the presence of barley. In our conditions, the allelopathic activity of barley root exudates had no apparent relationship with the size of the root and a prominent action of genetic determinants in the allelopathic potential between genotypes is proposed. The alloinhibitory activity of barley or great brome root exudates deferred between the receiver species but was always higher than the autoinhibition potential. The autoinhibition in barley proved to depend on whether the genotypes used as donor and receiver are identical or different, suggesting a specific interaction of allelochemicals with the receiver plant. These molecules seem to be the main actors in the allelopathic barley potential as external factors such variations of pH have no evident relevance in the inhibition process. Conclusions. Barley and great brome exude molecules in their surroundings. This affects the growth of the receiver plants, suggesting that these compounds might contribute to the plant community dynamics.
Diversité de la macrofaune des sols cultivés sur les Hautes-Terres de Madagascar
Authors: Rakotomanga Diane , Blanchart Éric , Rabary Bodovololona , Randriamanantsoa Richard , Razafindrakoto Malalatiana , Autfray Patrice
Published: February 2022

Description du sujet. L’article traite de la macrofaune du sol, composante clé du fonctionnement biologique du sol. Objectifs. Cette étude, réalisée en 2015, a eu pour objectif de tester l’effet de pratiques culturales et de systèmes de culture sur la macrofaune du sol dans une zone d’agriculture-élevage des Hautes-Terres de Madagascar. Cinq systèmes de culture ont été étudiés : cultures annuelles labourées annuellement avec apport de fumier modéré (LAMF) ou élevé (LAEF), cultures fourragères pérennes sans labour et avec apport de fumier élevé (CFEF), cultures annuelles en agriculture de conservation sans labour et apport de fumier modéré (ACMF) et pâturages permanents, non labourés et sans apport de fumier (PP0F). Méthode. Pour chaque système de culture, 12 parcelles d’expérimentation ou d’exploitation agricole ont fait l’objet d’un échantillonnage de la macrofaune du sol avec cinq monolithes de sol par parcelle, sur 30 cm de profondeur. Résultats. Cinquante-deux espèces d’invertébrés, classées en 15 ordres taxonomiques et 6 groupes fonctionnels, ont été identifiées. Pour les cultures annuelles sans labour, l’absence de travail du sol a favorisé la diversité taxonomique et la densité de la macrofaune, n’a pas réduit la densité des vers blancs (larves de Coléoptères Scarabeoideae) rhizophages mais a entrainé une diminution des densités de vers de terre par rapport au mode de culture fourragère. En systèmes labourés, l’intensité d’application du fumier n’a eu d’effet ni sur les vers blancs ni sur les vers de terre. Conclusions. Cette étude sur la macrofaune du sol dans cette région de Madagascar a permis de mieux percevoir les pratiques et les systèmes les plus favorables aux invertébrés utiles (comme les vers de terre) et plus défavorables aux invertébrés nuisibles (comme les vers blancs). Ceci permettra d’orienter les paysans dans la gestion de leurs terres.
Effet du biochar sur la biodisponibilité du phosphore dans un sol limoneux acide
Authors: Houben David , Hardy Brieuc , Faucon Michel-Pierre , Cornelis Jean-Thomas
Published: February 2022

Description du sujet. Cet article traite de l’impact du biochar sur la biodisponibilité en phosphore (P) dans les sols en vue d’améliorer la gestion et l’autonomie de la fertilisation en P des cultures. Objectifs. L’objectif général était d’explorer le potentiel du biochar à augmenter la biodisponibilité du P dans le sol. Les objectifs spécifiques étaient de préciser l’influence de la biomasse pyrolysée ainsi que la dose de biochar appliquée sur la solubilité du P. Méthode. Trois biochars produits à partir de biomasses différentes (résidus de Miscanthus, de bois et de café) ont été incorporés dans un Luvisol (pH acide) selon deux doses (1 et 3 % en masse). Après 76 jours d’incubation, la biodisponibilité du P a été estimée (extraction au CaCl2 0,01 M). Les propriétés physico-chimiques du sol et la quantité de CO2 émise durant la période d’incubation ont également été déterminées. Résultats. Seul le biochar produit à partir de résidus de bois et incorporé à une dose de 3 % a augmenté la concentration en P biodisponible dans le sol (+ 75 %). Cette augmentation résulterait non seulement d’une libération de P par le biochar lui-même (effet direct), mais également d’une remobilisation du P du sol (effet indirect) faisant suite à l’élévation drastique du pH (+ 3,6 unités) ainsi qu’à l’augmentation de l’activité biologique. Pour les autres traitements, l’absence d’effet significatif sur la biodisponibilité du P résulte vraisemblablement de leur faible impact sur le pH du sol, celui-ci restant dans une gamme (4,3 – 5,1) favorisant l’insolubilisation du P. Conclusions. Étant donné la variabilité des résultats et les incertitudes concernant les mécanismes responsables de la mobilisation du P en présence de biochar, il est essentiel de conduire des études complémentaires afin de mieux comprendre l’impact du biochar sur la mobilité du P dans les systèmes sol-plante.