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- Sitwe 23, a Complex ESA/MSA Locality in the Northern Luangwa Valley, ZambiaPublication . Bisson, Michael S.; Burke, Ariane; Schilt, Flora; Aleman, Julie; Peros, Matthew C.; Drapeau, Michelle; Katongo, Maggie; Kayuni, Martha Nchimunya; Museba, Joseph Mutale; Tolan, SteveThis paper describes the lithic aggregates from Sitwe 23 (SW23), a Stone Age locality in a previously unstudied region of the northern Luangwa Valley, Zambia. This area yielded two surface lithic scatters containing abundant artifacts derived from Pleistocene sediments on uplifted terrain and exposed by recent erosion on two adjacent terraces. The scatters are time-averaged palimpsests formed by deflation, but most of the lithics lack evidence of significant fluvial transport or post-depositional damage, indicating minimal horizontal displacement. Typological and attribute analyses of samples from both spurs reveal predominantly simple and expedient core and flake technologies, as well as sophisticated biface manufacture and Levallois technique producing flakes and points that are differentially distributed between the terraces. The artifacts identified in this analysis include types conventionally considered diagnostic of the Acheulean, Sangoan, and Middle Stone Age, suggesting that the collections may document one or more temporal windows during the Chibanian age (770-126 ka). Whether artifacts in these samples were originally deposited sequentially or concurrently is not yet known and alternative hypotheses are presented and discussed. The collections are compared to sites in Zambia and the northern Lake Malawi basin and found to be similar technologically but typologically different. Given the paucity of previously known Ston Age archaeological sites in the region, our work now demonstrates that northern Luangwa has significant archaeological potential and deserves further study. Cet article d & eacute;crit les agr & eacute;gats lithiques de Sitwe 23 (SW23), un site de l'Acirc;ge de pierre situ & eacute; dans une r & eacute;gion auparavant non & eacute;tudi & eacute;e de la vall & eacute;e septentrionale de Luangwa en Zambie. Deux dispersions lithiques en surface, sur deux terrasses adjacentes, ont & eacute;t & eacute; identifi & eacute;es sur un terrain sur & eacute;lev & eacute; et expos & eacute;s par une & eacute;rosion r & eacute;cente, chacune contenant de nombreux artefacts provenant de s & eacute;diments pl & eacute;istoc & egrave;nes. Ces dispersions sont des palimpsestes moyenn & eacute;s dans le temps, form & eacute;s par d & eacute;flation, mais la plupart des artefacts lithiques ne montrent pas d'& eacute;vidences de transport fluvial significatif ou de dommages post-d & eacute;positionnels, indiquant un d & eacute;placement horizontal minimal. Les analyses typologiques et d'attributs des deux zones r & eacute;v & egrave;lent la pr & eacute;dominance d'une technologie d'& eacute;clats et de nucleus simple et exp & eacute;ditive, combin & eacute;e & agrave; une fabrication sophistiqu & eacute;e de bifaces ainsi que d'& eacute;clats et de pointes de technique Levallois qui sont r & eacute;partis de mani & egrave;re diff & eacute;rentielle entre les terrasses. Les artefacts identifi & eacute;s dans cette analyse comprennent des types g & eacute;n & eacute;ralement consid & eacute;r & eacute;s comme diagnostiques de l'Acheul & eacute;en, du Sangoan et du Middle Stone Age, sugg & eacute;rant que les collections pourraient documenter une ou plusieurs fen & ecirc;tres temporelles du Chibanien (770-126 ka). Comme on ignore si ces art & eacute;facts ont & eacute;t & eacute; d & eacute;pos & eacute;s de mani & egrave;re s & eacute;quentielle ou simultan & eacute;e, diff & eacute;rentes hypoth & egrave;ses sont pr & eacute;sent & eacute;es et discut & eacute;es. Des comparaisons de ces collections & agrave; d'autres sites en Zambie et dans le bassin septentrional du lac Malawi r & eacute;v & egrave;lent qu'elles sont technologiquement similaires mais typologiquement diff & eacute;rentes. Compte tenu du manque de sites arch & eacute;ologiques de l'Acirc;ge de pierre connus dans la r & eacute;gion, nos travaux d & eacute;montrent d & eacute;sormais que le nord de vall & eacute;e de la Luangwa poss & egrave;de un potentiel arch & eacute;ologique significatif et m & eacute;rite des recherches suppl & eacute;mentaires.
- Evaluating the success of vegetation restoration in rewilded salt marshesPublication . Carneiro, Inês; Carrasco, Rita; Didderen, Karin; Sousa, Ana I.Floodbank realignment is a common practice aimed at restoring salt marsh vegetation on previously embanked land. However, experiences indicate that it may take several years before salt marsh vegetation becomes fully established. Various challenges arising from ecogeomorphic feedback mechanisms could pose significant setbacks to vegetation recolonization. The widespread adoption of transplantation techniques for the restoration and rehabilitation of rewilded landscapes has indeed proven to be a valuable tool for accelerating plant development. In the Ria Formosa coastal lagoon (South of Portugal), a pilot plan was implemented, and two salt marsh pioneer species, Spartina maritima (syn. Sporobolus maritimus ) and Sarcocornia perennis (syn. Salicornia perennis ), were transplanted from a natural salt marsh to a rewilded marsh. Biodegradable 3D porous structures were installed to mimic transplant clumping, aid sedimentation, and enhance the plant ' s initial adjustment. Ecological, sediment, and hydrodynamic data were collected during the 12-month pilot restoration plan. The environmental profiles of the donor and restoration sites were compared to substantiate the success of the transplants in the rewilded salt marsh. Results show that although plant shoot density decreased after the transplanting, Spartina maritima acclimated well to the new environmental conditions of the restoration site, showing signs of growth and cover increase, whilst Sarcocornia perennis was not able to acclimatize and survive in the restoration site. The failure behind the Sarcocornia perennis acclimation might be related to the bed properties and topographic properties of the restoration site in the rewilded marsh. Major findings contribute to a more comprehensive understanding of how salt marsh pioneering vegetation successfully colonizes disturbed habitats, facilitated using 3D -biodegradable structures.
- Stimulating customer participation behaviour and boosting value co-creation in hotelsPublication . Sadighha, Jinous; Pinto, Patrícia; Guerreiro, Manuela; Campos, Ana CláudiaConsidering the competitive environment of the hospitality industry in delivering superior value to customers, customer participation in value co-creation with the service provider through interaction becomes pivotal. By bonding the co-creation theory with the equity theory, this study proposes a model for stimulating customer participation behaviour (CPB), which includes customer co-creation perception (CCCP) composing DART activities (dialogue, access, risk assessment, and transparency), CPB, co-production, and value-in-use. The collected data from tourists staying in hotels in Portugal was analysed using Partial Least Squares Structural Equation Modeling (PLS-SEM). The results confirm that CCCP predicts CPB, co-production, and value-in-use. Moreover, CPB improves co-production and value-in-use and mediates the associations between CCCP and co-production/ value-in-use. This research contributes to co-creation theory by confirming CCCP as a driver of CPB and provides practical implications to enhance co-production and value-in-use in hotels.
- Circular economy and agriculture: mapping circular practices, drivers, and barriers for traditional table-olive grovesPublication . MARTINEZ MORENO, MARIA MAGDALENA; Buitrago Esquinas, Eva María; Yñiguez, Rocío; Puig-Cabrera, MiguelThe Circular Economy (CE) has notable potential for the economic, environmental, and social sustainability of agriculture. However, the literature on the CE has focused on the industrial sector, leaving significant gaps in the analysis of sustainable circular models in agriculture. In the case of traditional table-olive cultivation, which suffers from serious competitiveness problems, the possibilities of the CE are particularly relevant. Given the lack of previous research for the sector, this work aims to map the circular practices carried out in traditional tableolive groves and identify their drivers and barriers. To this end, an exploratory methodology of mixed approaches is proposed that combines desk research, observational fieldwork, focus groups with stakeholders and experts, and farmers’ in-depth interviews. This methodology can be generalised to other crops. The results obtained have enabled up to 59 practices to be brought to light throughout all stages of the life cycle of olive cultivation, which cover all the principles and strategies of the CE. Plant covers, the use of eco-efficient techniques, the repair and sharing of machinery and tools, and the management of organic outputs stand out. The collaborative economy and institutional support were identified as the main drivers, while technical-economic barriers and regulatory limitations constitute the main obstacles detected. Based on these results, three groups of recommendations are proposed as a guide to future policies for which certain CE practices are highlighted: increase financial incentives, create a stable legislative framework, and reinforce incentives for the collaborative economy.
- Impact of persistently high sea surface temperatures on the rhizobiomes of Zostera marina in a Baltic Sea benthocosmsPublication . Cúcio, Catarina; Brakel, Janina; Weinberger, Florian; Wahl, Martin; Teles, Ana; Muyzer, Gerard; Aires, Tania; Engelen, AschwinPersistently high marine temperatures are escalating and threating marine biodiversity. The Baltic Sea, warming faster than other seas, is a good model to study the impact of increasing sea surface temperatures. Zostera marina, a key player in the Baltic ecosystem, faces susceptibility to disturbances, especially under chronic high temperatures. Despite the increasing number of studies on the impact of global warming on seagrasses, little attention has been paid to the role of the holobiont. Using an outdoor benthocosm to replicate near-natural conditions, this study explores the repercussions of persistent warming on the microbiome of Z. marina and its implications for holobiont function. Results show that both seasonal warming and chronic warming, impact Z. marina roots and sediment microbiome. Compared with roots, sediments demonstrate higher diversity and stability throughout the study, but temperature effects manifest earlier in both compartments, possibly linked to premature Z. marina die-offs under chronic warming. Shifts in microbial composition, such as an increase in organic matter-degrading and sulfur-related bacteria, accompany chronic warming. A higher ratio of sulfate-reducing bacteria compared to sulfide oxidizers was found in the warming treatment which may result in the collapse of the seagrasses, due to toxic levels of sulfide. Differentiating predicted pathways for warmest temperatures were related to sulfur and nitrogen cycles, suggest an increase of the microbial metabolism, and possible seagrass protection strategies through the production of isoprene. These structural and compositional variations in the associated microbiome offer early insights into the ecological status of seagrasses. Certain taxa/genes/pathways may serve as markers for specific stresses. Monitoring programs should integrate this aspect to identify early indicators of seagrass health. Understanding microbiome changes under stress is crucial for the use of potential probiotic taxa to mitigate climate change effects. Broader-scale examination of seagrass-microorganism interactions is needed to leverage knowledge on host-microbe interactions in seagrasses.
- Comparing environmental impacts of deep‐seabed and land‐based mining: a defensible frameworkPublication . A. Metaxas; Anglin, C. D.; Cross, A.; Drazen, J.; Haeckel, M.; Mudd, G.; Smith, C. R.; Smith, S.; Weaver, P. P. E.; Sonter, L.; Amon, D. J.; Erskine, P. D.; Levin, L. A.; Lily, H.; Maest, A. S.; Ramirez‐Llodra, E.; Sánchez, L. E.; Sharma, R.; Vanreusel, A.; Wheston, S.; Tunnicliffe, V.; Mestre, NéliaThe crises of climate change and biodiversity loss are interlinked and must be addressed jointly. A proposed solution for reducing reliance on fossil fuels, and thus mitigating climate change, is the transition from conventional combustion-engine to electric vehicles. This transition currently requires additional mineral resources, such as nickel and cobalt used in car batteries, presently obtained from land-based mines. Most options to meet this demand are associated with some biodiversity loss. One proposal is to mine the deep seabed, a vast, relatively pristine and mostly unexplored region of our planet. Few comparisons of environmental impacts of solely expanding land-based mining versus extending mining to the deep seabed for the additional resources exist and for biodiversity only qualitative. Here, we present a framework that facilitates a holistic comparison of relative ecosystem impacts by mining, using empirical data from relevant environmental metrics. This framework (Environmental Impact Wheel) includes a suite of physicochemical and biological components, rather than a few selected metrics, surrogates, or proxies. It is modified from the "recovery wheel" presented in the International Standards for the Practice of Ecological Restoration to address impacts rather than recovery. The wheel includes six attributes (physical condition, community composition, structural diversity, ecosystem function, external exchanges and absence of threats). Each has 3-5 sub attributes, in turn measured with several indicators. The framework includes five steps: (1) identifying geographic scope; (2) identifying relevant spatiotemporal scales; (3) selecting relevant indicators for each sub-attribute; (4) aggregating changes in indicators to scores; and (5) generating Environmental Impact Wheels for targeted comparisons. To move forward comparisons of land-based with deep seabed mining, thresholds of the indicators that reflect the range in severity of environmental impacts are needed. Indicators should be based on clearly articulated environmental goals, with objectives and targets that are specific, measurable, achievable, relevant, and time bound. The crises of climate change and biodiversity loss are interlinked and must be addressed jointly. A proposed solution for reducing reliance on fossil fuels, and thus mitigating climate change, is the transition from conventional combustion-engine to electric vehicles which currently requires additional mineral resources. Most options to meet this demand are associated with some biodiversity loss. One proposal is to mine the deep seabed, a vast, relatively pristine and mostly unexplored region of our planet. We present a framework that facilitates a holistic comparison of relative ecosystem impacts by mining, using empirical data from relevant environmental metrics.image.
- Behind the waterfall - interdisciplinary results from holley shelter and their implications for understanding human behavioral patterns at the end of the middle stone age in Southern AfricaPublication . Bader, Gregor D.; Val, Aurore; Edwin Gevers; Rhodes, Sara E.; Stahl, Nina; Woodborne, Stephan; Will, ManuelHolley Shelter is a Middle (MSA) and Later Stone Age (LSA) site in KwaZulu-Natal, South Africa. The rock shelter is located at the intersection of three ecosystems, in a strip of the Savanna Biome between the Grassland and Indian Ocean Coastal Belt Biomes. Initial excavations in the 1950s by Gordon Cramb yielded large amounts of unifacial points and splintered pieces, as well as organic remains associated with MSA occupations. Our comparative techno-typological evaluation of this material in 2015 suggested the occupations may date to early MIS 3. We then initiated new excavations at the site using modern field methods and controlled sampling for lithic and organic material. Following the initial round of interdisciplinary analysis, we herein report the first absolute ages for Holley Shelter, a detailed technological analysis of new lithic material from the uppermost MSA layers at the site, and a preliminary study of the associated faunal remains. A set of 12 C-14 dates place these occupations within a constricted chronological period dated to similar to 36,000-34,000 cal. BP that overlaps with the so-called 'final MSA'. The hornfels-dominated lithic assemblages are characterized by diverse core technologies oriented toward the production of laminar products, which include bladelets and abundant splintered pieces. The zooarchaeological analysis documents an emphasis on open grasslands that provided the bulk of the animal prey exploited by the inhabitants of the shelter, with a preference for medium-sized antelopes. Three bone retouchers, a rare occurrence in southern African MSA contexts, were identified in the faunal assemblage. The archaeological deposits at Holley Shelter reflect short-term, potentially seasonal, and specialized occupations that could be influenced by its ecological position. The archaeological material exhibits marked discrepancies with other well-dated final MSA assemblages such as those from Sibhudu, Umbeli Belli, Sibebe and Border Cave. This illustrates considerable variability and a complex spatio-temporal patterning of behavioral adaptations and cultural traditions at the end of the MSA in southern Africa.
- gys1 regulates maternal glycogen reserve essential for embryonic development in zebrafishPublication . Chen, Jie; Ji, Xiao; Gao, Jing; Huang, Jiao; Ren, JianfengThe reserve of glycogen is essential for embryonic development. In oviparous fish, egg is an isolated system after egg laying with all the required energy deposits by their mothers. However, the key regulated factor mediates the storage of maternal glycogen reserve which support for embryogenesis in the offspring is largely unknown. Glycogen synthase (GYS) is a central enzyme for glycogen synthesis. In our previous study, we generated a gys1 knockout zebrafish line, showed an embryonic developmental defect in F3 generation. In this study, firstly we determined that the gys1 was maternal origin by backcrossing the F2 mutant with wildtype lines. PAS staining and glycogen content measurement showed that glycogen reserve was reduced both in ovaries and embryos in the mutant group compared to wildtypes. Free glucose measurement analysis showed a 50 % of reduction in gys1 mutant embryos compared to wildtype embryos at 24 hpf; showed an approximal 50 % of reduction in gys1 mutant adults compared to wildtypes. Microinjection of 2-NBDG in embryos and comparison of fluorescent signal demonstrated that glucose uptake ability was decreased in the mutant embryos, indicating an impaired glucose metabolism. Untargeted metabolomics analysis then was employed and revealed that key modified metabolites enriched into vitamin B pathway, carbohydrate and unsaturated fatty acid pathways. These results demonstrated that gys1 played a role on glycogen metabolism, involved into the maternal glycogen reserve which essentially contribute to embryonic development.
- Sugars and phenols in carob tree fruits from different producing countries: a short reviewPublication . Correia, Pedro José; Pestana, MaribelaIn the last two decades, important advances have been made in the chemical analysis of the fruit of carob tree. After harvesting, the fruits (also known as dry pods) are ground. The seeds can then be separated from the pulp, which represents 80–90 % of a pod's weight. The health benefits of carob pulp derivatives are well-recognized, and carob pulp-based food products are becoming increasingly available to consumers. The major carob-producing countries are in southern Europe and northern Africa, including the Mediterranean islands, and carob pulp products are normally prepared and consumed regionally. In this review, we compare the sugar and phenol profiles of carob pods harvested from different countries in the Mediterranean basin while accounting for the different cultivars and soil conditions in each sample area. We conclude that pod nutritional composition varies widely among countries, making it necessary for future, multi-year studies to more closely evaluate how climate and soil properties affect the phenol and sugar contents of fruits from the same trees or cultivars.
- Machine learning unveils the action of different endogenous phenolic compounds present or formed along the rooting development in olive stem cuttingsPublication . Santos-Rufo, Antonio; Rodríguez Solana, Raquel; Fernández-Recamales, Ángeles; Sayago-Gómez, Ana; Weiland-Ardáiz, CarlosChanges in the endogenous phenolic content of plant rooting could be influenced by genotype, hormones, or the interaction of both factors, thus modifying the plant rooting capacity/ability along the rooting development. In this study, the combined effects of IBA treatment and cultivar capacity on the rooting development of olive cuttings were modeled by the temporary assessment of simple and total phenolic content (TPC). Rooting ability and phenolic profile were monitored. Results indicated the lowest cumulative rooting in `Lechin-de-Sevilla´, and the highest rooting speed during the first days of the trial in high-rooting cultivars (‘Verdial-de-Hu´evar’ and ‘Arbequina’). A total of 14 phenolic compounds comprising phenolic acids and aldehyde (8), flavonoids (5), and a glycosylated seco-iridoid were quantified in rooted olive cuttings. Most of the phenolics presented a significant higher concentration in the ‘Lechin-de-Sevilla’ cultivar, except for the ferulic acid and luteolin, as well the TPC that varied as did the rooting parameter. At the end of the rooting trial (60 days), luteolin in `Verdial de Hu´evar’ and `Gordal sevillana’ cultivars and ferulic acid in `Lechin de Sevilla’ were the phenolics exclusively found in the highest concentrations. Time did not affect vanillin and oleuropein, although in the case of high-rooting cultivars, values for these compounds were almost constant, while in low- or medium-rooting cultivars, by general, increased or decreased, respectively. The Random Forest algorithm allowed to predict from a complex number of variables, which affected the rooting ability of olive cuttings independently of the cultivar and auxin treatment, finding that luteolin was the best indicator over time.