Iskorištavanje dječjeg rada u Yaoundéu – Kamerunu: poučeni iskustvima iz provedene ankete djece

Although child labour is a phenomenon widely studied around the world, there are few papers that tackle the problem in Cameroon. The objective of this paper is to fill the gap by questioning the subject in Yaoundé, the capital city. But child labour phenomenon is analysed here from a questionnaire that has two distinctive features: (i) the questionnaire is exclusively devoted to child labour, and (ii) all the participants in the survey are exclusively children themselves. No adult (parent, guardian, elder, employer, etc.) was consulted and given a chance to answer on behalf of a child. This process is extremely rare in child labour, since in general individuals other than children are requested to testify and answer inslead of children. While some results obtained from a standard Logit model on the determinant of child labour are well known, the others are either not known or insignificant. We suspect that the reason is the data collection.Sažetak Iako se problem iskorištavanja dječjeg rada proučava diljem svijeta, malobrojne su studije koje se bave tim problemom u Kamerunu. Cilj ovog članka je popuniti prazninu istraživanjem ove pojave u glavnom gradu – yaoundé. Istraživanje fenomena dječjeg rada prvenstveno se temeljio na: (i) upitniku koji je isključivo bio usredotočen na problem dječjeg rada, i (ii) na ispitivanju djece-radnika kao glavnim sudionicima u istraživanju. Ovo je jedinstven primjer, jer odrasli (roditelji, skrbnici, poslodavci i sl.) nisu bili uključeni u istraživanje, budući da su u prethodnim istraživanjima iskorištavanja dječjeg rada, ispitanici bili odrasli koji su u ime djece popunjavali upitnike. U usporedbi s primjenom standardnog Logit modela o određivanju dječjeg rada čiji rezultati su općepoznati, primjena drugih modela rezultira ili nepoznatim ili gotovo beznačajnim činjenicama, što navodi na sumnju o ispravnosti prikupljanja podataka

TECHNOLOGICAL INNOVATIONS AND STRUCTURAL TRANSFORMATION IN AFRICAN ECONOMIES

This paper examines the role of technological innovations on structural transformation on economies of Africa. To attain this objective, it uses a sample of 32 African countries. The estimation techniques are system GMM and two stage least Square. Results indicate that technological innovations, as measured by total patents applications, have a significant effect on per sector value added. This result supports the almost nonlinear relationship of structural transformation since this study shows that manufacturing is the dominant sector in the promotion of structural changes as far as the implementation of technological innovations is concerned. Also, our results highlight that with regards to the African context, manufacturing is the sector in which technological innovation has the greatest impact on per sector value added and by so doing, it promotes structural transformation than other sectors (services or agriculture sector). As policy implication, governments need to encourage technological infrastructure through private and public spending on research and development especially for agricultural development to foster structural transformation

Assessing the effects of climate change on arthropod abundance in Azorean pastures: PASTURCLIM project's baseline monitoring data

Background The data we present are part of the project PASTURCLIM (Impact of climate change on pasture’s productivity and nutritional composition in the Azores). The project aims to assess the consequences of climate change (e.g. temperature increase) on the grass production and its quality for forage, as well as to assess changes in the arthropod communities associated with the Azorean intensive pastures. An in situ experiment was set up using Open Top Chambers (OTCs), in order to simulate an increasing of temperature (average of +1.2ºC) on pastures. In this contribution, we present the data relative to the arthropod sampling. New information We provide an inventory of all arthropods recorded inside OTCs and in control plots in three intensively managed pastures dominated by grasses in Terceira Island (Azores): two of them dominated by ryegrass, Lolium multiflorum Lam. (Poaceae), located respectively at 186 m and 301 m above sea level; and one field dominated by common velvetgrass, Holcus lanatus L. (Poaceae), located at an altitude of 385 m. A total of 41351 specimens were collected. Organisms collected belong to four classes, 15 orders, 60 families and 171 species/morphospecies (including 34 taxa identified only at order, family or genus level). Therefore, for only 137 taxa, we have a scientific name associated (n = 38918). A total of 75% of the species (n = 129 species) are considered introduced (including all the species with indeterminate colonisation status that are possibly also exotic species (n = 7622)), representing 71% of the total abundance (n = 29664 specimens). A total of 19% of the species (n = 33 species) are considered native non-endemic representing 28% of the total abundance (n = 11608 specimens). Only one endemic species was sampled, the wolf spider Pardosa acorensis Simon, 1883 (1% of the species), representing 0.2% of the total abundance (n = 79 specimens). Spiders (5056 specimens) and beetles (18310 specimens) were the dominant taxa representing, respectively, 20 and 78 morphospecies. Since the main aim of this study was to have a better knowledge on arthropod communities present in Azorean pastures under a simulated temperature increase, the principal novelty of this paper is the contribution with distribution and abundance data to a baseline knowledge on the future consequences of climate changes on arthropod communities in Azorean pastures.info:eu-repo/semantics/publishedVersio

Arthropods and other biota associated with the Azorean trees and shrubs : Laurus azorica (Seub) Franco (Magnoliophyta, Magnoliopsida, Laurales, Lauraceae)

This study explores the composition and structure of species communities associated with the native Azorean tree species Laurus azorica (Seub) Franco (Magnoliophyta, Magnoliopsida, Laurales, Lauraceae). Communities were sampled in six Islands covering the occidental (Flores), central (Faial, Pico, Terceira) and eastern (São Miguel, Santa Maria) groups of Azores Archipelago during the BALA project, using standardised sampling protocols for surveying canopy arthropod fauna. In addition, the study characterises the distribution of species regarding their colonisation status and feeding modes and, finally, compares communities of different Islands. Ninety-four arthropod species totalling 10,313 specimens were collected on L. azorica. The Arthropod community was dominated by Hemiptera species, most of them being herbivores. Endemic and native species showed a very high abundance representing about 94% of the total species abundance. However, despite introduced species being represented by few individuals (6% of the total abundance), their diversity was remarkable (28 species and no significant difference with diversity found in endemic and native species communities). Analysis of rarity patterns revealed a stable community of endemic species (alpha gambin SAD model approaching a log-normal shape), intermediate stable community of native species (alpha SAD gambin model approaching a poisson log-normal) and a less stable community of introduced species (alpha SAD gambin model approaching a log-series shape). A dissimilarity analysis revealed high similarity between communities of Terceira and Pico and high dissimilarity between Flores and Faial communities. We observed a clear individualisation of the different islands when considering endemic species, whereas we observed high overlap when considering native and introduced species groups. Canopy community distribution confirms the results obtained in a previous study which suggest the stability of native and endemic arthropods species communities over introduced species community in native forests fragments. Arthropod species were richer than bryophytes, lichens and vascular plants species. We found that L. azorica serve as the substrate for very few vascular plants species (four epiphytes species), which were present in all Islands, except Elaphoglossum semicylindricum, which does not occur in Santa Maria. L. azorica shelters a significant number of bryophytes and lichens species. Thirty-two lichens and 92 bryophyte species, including 57 liverworts and 35 mosses, are referred to this phorophyte. Five bryophyte species, all Azorean endemics, are considered Endangered by IUCN Criteria. L. azorica harbours a poor community of epiphyte vascular plant species and all of them were ferns, but the community of bryophytes and lichens are not negligible although very low compared to the community found on other previously studied Azorean trees, the Azorean cedar Juniperus brevifolia. The present study shows that most islands present particular species distribution patterns without geographical correlation and that conservation programmes should be adapted to each Island. The study, therefore, calls for a specialisation of conservation programmes for each of the Islands.NT and MTF are currently funded by the project LIFE BEETLES (LIFE 18 NAT/PT/000864) at "Secretaria Regional do Ambiente e Alterações Climáticas". PAVB, RE and RG are funded by the project AZORESBIOPORTAL-PORBIOTA (ACORES-01-0145FEDER-000072) (2019).info:eu-repo/semantics/publishedVersio

SLAM Project - Long Term Ecological Study of the Impacts of Climate Change in the Natural Forest of Azores: II - A survey of exotic arthropods in disturbed forest habitats

BACKGROUND: The data we present consist of an inventory of exotic arthropods, potentially invasive, collected in exotic and mixed forests and disturbed native forest patches of the Azores Archipelago. The study was carried out between 2019 and 2020 in four islands: Corvo, Flores, Terceira and Santa Maria, where a total of 45 passive flight interception SLAM traps were deployed, during three to six consecutive months. This manuscript is the second contribution of the “SLAM Project - Long Term Ecological Study of the Impacts of Climate Change in the Natural Forest of Azores”. NEW INFORMATION: We provide an inventory of terrestrial arthropods belonging to Arachnida, Diplopoda, Chilopoda and Insecta classes from four Azorean islands. We identified a total of 21,175 specimens, belonging to 20 orders, 93 families and 249 species of arthropods. A total of 125 species are considered introduced, 89 native non-endemic and 35 endemic. We registered 34 new records (nine for Corvo, three for Flores, six for Terceira and 16 for Santa Maria), of which five are new for Azores, being all exotic possibly recently introduced: Dieckmanniellus nitidulus (Gyllenhal, 1838), Gronops fasciatus Küster, 1851, Hadroplontus trimaculatus (Fabricius, 1775), Hypurus bertrandi (Perris, 1852) (all Coleoptera, Curculionidae) and Cardiocondyla mauritanica Forel, 1890 (Hymenoptera, Formicidae). This publication highlights the importance of planted forests and disturbed native forest patches as reservoirs of potentially invasive arthropods and refuges for some rare relict endemic arthropod species.Trap acquisition and fieldwork were funded by the projects: Portuguese National Funds, through FCT – Fundação para a Ciência e a Tecnologia, within the project UID/BIA/ 00329/2013-2023; Direcção Regional do Ambiente - PRIBES (LIFE17 IPE/PT/000010) (2019-2020); Direcção Regional do Ambiente – LIFE-BETTLES (LIFE18 NAT_PT_000864) (2020-2024); AZORESBIOPORTAL – PORBIOTA (ACORES-01-0145-FEDER-000072) (2019-2022). The database management and Open Access was funded by the project “MACRISK-Traitbased prediction of extinction risk and invasiveness for Northern Macaronesian arthropods” Fundação para a Ciência e a Tecnologia (FCT) - PTDC/BIA-CBI/0625/2021 (2022-2024). MB was supported by FCT - DL57/2016/CP1375/CT0001. NT and MTF were supported by the project LIFE-BETTLES (LIFE18 NAT_PT_000864).info:eu-repo/semantics/publishedVersio

SLAM Project - Long Term Ecological Study of the Impacts of Climate Change in the Natural Forest of Azores: III - Testing the impact of edge effects in a native forest of Terceira Island

BACKGROUND: The data we present are part of the long-term project “SLAM Project - Long Term Ecological Study of the Impacts of Climate Change in the Natural Forest of Azores” that started in 2012, aiming to understand the impact of biodiversity erosion drivers on Azorean native forests (Azores, Macaronesia, Portugal). The data for the current study consist in an inventory of arthropods collected in three locations of a native forest fragment at Terra-Brava protected area (Terceira, Azores, Portugal) aiming to test the impact of edge effects on Azorean arthropod communities. The three locations were: (i) the edge of the forest, closer to the pastures; (ii) an intermediate area (100 m from edge); and (iii) the deepest part of the native forest fragment (more than 300 m from edge). The study was carried out between June 2014 and December 2015. A total of nine passive flight interception SLAM (Sea, Land and Air Malaise) traps were deployed (three in each of the studied locations), during 18 consecutive months. This study provides the raw data to investigate temporal and edge effect variation for the Azorean arthropod communities. NEW INFORMATION: The collected arthropods belong to a wide diversity of taxonomic groups of Arachnida, Diplopoda, Chilopoda and Insecta classes. We collected a total of 13,516 specimens from which it was possible to identify to species level almost all specimens (13,504). These identified specimens belong to 15 orders, 58 families (plus three with only genus or family level identification) and 97 species of arthropods. A total of 35 species are considered introduced, 34 native non-endemic and 28 endemic. Additionally, a total of 10 taxa (12 specimens) were recorded at genus, family or order level. This dataset will allow researchers to test the impact of edge effect on arthropod biodiversity and to investigate seasonal changes in Azorean arthropod native forest communities.Trap acquisition and fieldwork were funded by the project Portuguese National Funds, through FCT - Fundação para a Ciência e a Tecnologia, within the project UID/BIA/00329/2013-2023. The database management and Open Access was funded by the project "MACRISK-Trait-based prediction of extinction risk and invasiveness for Northern Macaronesian arthropods" Fundacao para a Ciencia e a Tecnologia (FCT) -PTDC/BIA-CBI/0625/2021 (2022-2024). MB was supported by FCT - DL57/2016/CP1375/CT0001. NT and MTF were supported by the project LIFE-BETTLES (LIFE18 NAT/PT/000864). PAVB and RG were additionally supported by FCT-UIDP/00329/2020-2024 (Thematic Line 1-Integrated ecological assessment of environmental change on biodiversity) and MACRISK - PTDC/BIA-CBI/0625/2021, through the FCT - Fundacao para a Ciencia e a Tecnologia.info:eu-repo/semantics/publishedVersio

High-K dielectric sulfur-selenium alloys.

Upcoming advancements in flexible technology require mechanically compliant dielectric materials. Current dielectrics have either high dielectric constant, K (e.g., metal oxides) or good flexibility (e.g., polymers). Here, we achieve a golden mean of these properties and obtain a lightweight, viscoelastic, high-K dielectric material by combining two nonpolar, brittle constituents, namely, sulfur (S) and selenium (Se). This S-Se alloy retains polymer-like mechanical flexibility along with a dielectric strength (40 kV/mm) and a high dielectric constant (K = 74 at 1 MHz) similar to those of established metal oxides. Our theoretical model suggests that the principal reason is the strong dipole moment generated due to the unique structural orientation between S and Se atoms. The S-Se alloys can bridge the chasm between mechanically soft and high-K dielectric materials toward several flexible device applications

Underwater adhesive using solid–liquid polymer mixes

Instantaneous adhesion between different materials is a requirement for several applications ranging from electronics to biomedicine. Approaches such as surface patterning, chemical cross-linking, surface modification, and chemical synthesis have been adopted to generate temporary adhesion between various materials and surfaces. Because of the lack of curing times, temporary adhesives are instantaneous, a useful property for specific applications that need quick bonding. However, to this day, temporary adhesives have been mainly demonstrated under dry conditions and do not work well in submerged or humid environments. Furthermore, most rely on chemical bonds resulting from strong interactions with the substrate such as acrylate based. This work demonstrates the synthesis of a universal amphibious adhesive solely by combining solid polytetrafluoroethylene (PTFE) and liquid polydimethylsiloxane (PDMS) polymers. While the dipole-dipole interactions are induced by a large electronegativity difference between fluorine atoms in PTFE and hydrogen atoms in PDMS, strong surface wetting allows the proposed adhesive to fully coat both substrates and PTFE particles, thereby maximizing the interfacial chemistry. The two-phase solid–liquid polymer system displays adhesive characteristics applicable both in air and water, and enables joining of a wide range of similar and dissimilar materials (glasses, metals, ceramics, papers, and biomaterials). The adhesive exhibits excellent mechanical properties for the joints between various surfaces as observed in lap shear testing, T-peel testing, and tensile testing. The proposed biocompatible adhesive can also be reused multiple times in different dry and wet environments. Additionally, we have developed a new reactive force field parameterization and used it in our molecular dynamics simulations to validate the adhesive nature of the mixed polymer system with different surfaces. This simple amphibious adhesive could meet the need for a universal glue that performs well with a number of materials for a wide range of conditions

SLAM Project - Long Term Ecological Study of the Impacts of Climate Change in the natural forests of Azores: V - New records of terrestrial arthropods after ten years of SLAM sampling

BACKGROUND: A long-term study monitoring arthropods (Arthropoda) is being conducted since 2012 in the forests of Azorean Islands. Named "SLAM - Long Term Ecological Study of the Impacts of Climate Change in the natural forest of Azores", this project aims to understand the impact of biodiversity erosion drivers in the distribution, abundance and diversity of Azorean arthropods. The current dataset represents arthropods that have been recorded using a total of 42 passive SLAM traps (Sea, Land and Air Malaise) deployed in native, mixed and exotic forest fragments in seven Azorean Islands (Flores, Faial, Pico, Graciosa, Terceira, São Miguel and Santa Maria). This manuscript is the fifth data-paper contribution, based on data from this long-term monitoring project. NEW INFORMATION: We targeted taxa for species identification belonging to Arachnida (excluding Acari), Chilopoda, Diplopoda, Hexapoda (excluding Collembola, Lepidoptera, Diptera and Hymenoptera (but including only Formicidae)). Specimens were sampled over seven Azorean Islands during the 2012-2021 period. Spiders (Araneae) data from Pico and Terceira Islands are not included since they have been already published elsewhere (Costa and Borges 2021, Lhoumeau et al. 2022). We collected a total of 176007 specimens, of which 168565 (95.7%) were identified to the species or subspecies level. For Araneae and some Hemiptera species, juveniles are also included in this paper, since the low diversity in the Azores allows a relatively precise species-level identification of this life-stage. We recorded a total of 316 named species and subspecies, belonging to 25 orders, 106 families and 260 genera. The ten most abundant species were mostly endemic or native non-endemic (one Opiliones, one Archaeognatha and seven Hemiptera) and only one exotic species, the Julida Ommatoiulus moreleti (Lucas, 1860). These ten species represent 107330 individuals (60%) of all sampled specimens and can be considered as the dominant species in the Azorean native forests for the target studied taxa. The Hemiptera were the most abundant taxa, with 90127 (50.4%) specimens. The Coleoptera were the most diverse with 30 (28.6%) families. We registered 72 new records for many of the islands (two for Flores, eight for Faial, 24 for Graciosa, 23 for Pico, eight for Terceira, three for São Miguel and four for Santa Maria). These records represent 58 species. None of them is new to the Azores Archipelago. Most of the new records are introduced species, all still with low abundance on the studied islands. This publication contributes to increasing the baseline information for future long-term comparisons of the arthropods of the studied sites and the knowledge of the arthropod fauna of the native forests of the Azores, in terms of species abundance, distribution and diversity throughout seasons and years.AMCS is supported by the Ramón y Cajal program (RYC2020-029407-I), financed by the Spanish Ministerio de Ciencia e Innovación. IRA and MB were funded by Portuguese funds through FCT – Fundação para a Ciência e a Tecnologia, I.P., under the Norma Transitória – DL 57/2016/CP1375/CT0003 and DL 57/2016/CP1375/CT0001, respectively. Several projects supported the acquisition of traps during the last ten years, namely: EUFCT-NETBIOME –ISLANDBIODIV grant 0003/2011 (between 2012 and 2015); Portuguese National Funds, through FCT – Fundação para a Ciência e Tecnologia, within the project UID/BIA/00329/2013-2020; Direcção Regional do Ambiente - PRIBES (LIFE17 IPE/PT/ 000010) (2019); Direcção Regional do Ambiente – LIFE-BETTLES (LIFE18 NAT_PT_000864) (2020); AZORESBIOPORTAL – PORBIOTA (ACORES-01-0145- FEDER-000072) (2019); (FCT) - MACRISK-Trait-based prediction of extinction risk and invasiveness for Northern Macaronesian arthropods (FCT-PTDC/BIA-CBI/0625/2021) (2021-2022). Data curation and open Access of this manuscript were supported by the project MACRISK-Trait-based prediction of extinction risk and invasiveness for Northern Macaronesian arthropods (FCT-PTDC/BIA-CBI/0625/2021).info:eu-repo/semantics/publishedVersio