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Tallo: A global tree allometry and crown architecture database

Tommaso Jucker Jörg Fischer Jerome Chave David Coomes John Caspersen Arshad Ali Grace Jopaul Loubota Panzou Ted R. Feldpausch Daniel Falster Vladimir Andreevich Usoltsev Stephen Adu-Bredu Luciana Alves Mohammad Aminpour Bhely ANGOBOY Ilondea Niels Anten Cécile Antin yousef askari Rodrigo Muñoz Ayyappan Narayanan Patricia Balvanera Lindsay Banin Nicolas Barbier John J. Battles Hans Beeckman Yannick Enock Bocko Benjamin Bond_Lamberty Frans Bongers Samuel Bowers THOMAS BRADE Michiel van Breugel ARTHUR CHANTRAIN Rajeev Chaudhary JINGYU DAI Michele Dalponte Kangbéni Dimobe jean-christophe domec Jean-Louis Doucet Remko Duursma Moisés Enriquez KARIN Y. VAN EWIJK WILLIAM FARFAN_RIOS Adeline FAYOLLE ERIC FORNI David Forrester Hammad Gilani John Godlee Sylvie Gourlet-Fleury Matthias Haeni Jefferson Hall Jie He Andreas Hemp JOSE LUIS HERNANDEZ STEFANONI Steven Higgins ROBERT J. HOLDAWAY Kiramat Hussain Lindsay Hutley Tomoaki Ichie Yoshiko Iida Hai Jiang Puspa Raj Joshi Seyed Hasan Kaboli Maryam Kazempour Larsary Tanaka Kenzo Brian Kloeppel Takashi Kohyama Suwash Kunwar Shem Kuyah Jakub Kvasnica Siliang Lin Emily Lines Hongyan Liu CRAIG LORIMER Joel Loumeto Yadvinder Malhi Peter Marshall Eskil Mattsson Radim Matula Jorge Arturo Meave del Castillo Sylvanus Mensah XIANGCHENG MI Stephane MOMO Takoudjou Glenn Moncrieff Francisco Mora Sarath Nissanka Kevin O'Hara steven pearce Raphaël Pélissier Pablo Luis Peri Pierre Ploton Lourens Poorter mohsen javanmiri pour Hassan pourbabaei JUAN MANUEL DUPUY RADA Sabina Ribeiro Ryan Casey ANVAR SANAEI Jennifer Sanger Michael Schlund Giacomo Sellan Alexander Shenkin Bonaventure Sonké Frank Sterck Martin Svatek Kentaro Takagi Anna Trugman Farman Ullah Matthew Vadeboncoeur Ahmad Valipour Mark Vanderwel Alejandra Vovides Weiwei WANG Li Qiu Christian Wirth MURRAY WOODS Wenhua Xiang Fabiano de Aquino Ximenes Yaozhan Xu TOSHIHIRO YAMADA Miguel A. Zavala (2022, [Artículo])

Data capturing multiple axes of tree size and shape, such as a tree's stem diameter, height and crown size, underpin a wide range of ecological research—from developing and testing theory on forest structure and dynamics, to estimating forest carbon stocks and their uncertainties, and integrating remote sensing imagery into forest monitoring programmes. However, these data can be surprisingly hard to come by, particularly for certain regions of the world and for specific taxonomic groups, posing a real barrier to progress in these fields. To overcome this challenge, we developed the Tallo database, a collection of 498,838 georeferenced and taxonomically standardized records of individual trees for which stem diameter, height and/or crown radius have been measured. These data were collected at 61,856 globally distributed sites, spanning all major forested and non-forested biomes. The majority of trees in the database are identified to species (88%), and collectively Tallo includes data for 5163 species distributed across 1453 genera and 187 plant families. The database is publicly archived under a CC-BY 4.0 licence and can be access from: https://doi.org/10.5281/zenodo.6637599. To demonstrate its value, here we present three case studies that highlight how the Tallo database can be used to address a range of theoretical and applied questions in ecology—from testing the predictions of metabolic scaling theory, to exploring the limits of tree allometric plasticity along environmental gradients and modelling global variation in maximum attainable tree height. In doing so, we provide a key resource for field ecologists, remote sensing researchers and the modelling community working together to better understand the role that trees play in regulating the terrestrial carbon cycle. © 2022 The Authors. Global Change Biology published by John Wiley & Sons Ltd.

ALLOMETRIC SCALING CROWN RADIUS FOREST BIOMASS STOCKS FOREST ECOLOGY REMOTE SENSING STEM DIAMETER TREE HEIGHT BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

Does access to improved grain storage technology increase farmers' welfare? Experimental evidence from maize farming in Ethiopia

Hugo De Groote Bart Minten (2024, [Artículo])

Seasonal price variability for cereals is two to three times higher in Africa than on the international reference market. Seasonality is even more pronounced when access to appropriate storage and opportunities for price arbitrage are limited. As smallholder farmers typically sell their production after harvest, when prices are low, this leads to lower incomes as well as higher food insecurity during the lean season, when prices are high. One solution to reduce seasonal stress is the use of improved storage technologies. Using data from a randomised controlled trial, in a major maize-growing region of Western Ethiopia, we study the impact of hermetic bags, a technology that protects stored grain against insect pests, so that the grain can be stored longer. Despite considerable price seasonality—maize prices in the lean season are 36% higher than after harvesting—we find no evidence that hermetic bags improve welfare, except that access to these bags allowed for a marginally longer storage period of maize intended for sale by 2 weeks. But this did not translate into measurable welfare gains as we found no changes in any of our welfare outcome indicators. This ‘near-null’ effect is due to the fact that maize storage losses in our study region are relatively lower than previous studies suggested—around 10% of the quantity stored—likely because of the widespread use of an alternative to protect maize during storage, for example a cheap but highly toxic fumigant. These findings are important for policies that seek to promote improved storage technologies in these settings.

Hermetic Storage Randomised Controlled Trial CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA STORAGE PILOT FARMS SEASONALITY WELFARE MAIZE

Tensile behavior of 3D printed polylactic acid (PLA) based composites reinforced with natural fiber

Eliana M Agaliotis BALTAZAR DAVID AKE CONCHA ALEJANDRO MAY PAT Juan Pablo Morales Arias Celina Bernal Alex Valadez González Pedro Jesús Herrera Franco Gwenaelle Proust JUAN FRANCISCO KOH DZUL José Gonzalo Carrillo Baeza Emmanuel Alejandro Flores Johnson (2022, [Artículo])

Natural fiber-reinforced composite (NFRC) filaments for 3D printing were fabricated using polylactic acid (PLA) reinforced with 1–5 wt% henequen flour comprising particles with sizes between 90–250 μm. The flour was obtained from natural henequen fibers. NFRCs and pristine PLA specimens were printed with a 0° raster angle for tension tests. The results showed that the NFRCs’ measured density, porosity, and degree of crystallinity increased with flour content. The tensile tests showed that the NFRC Young’s modulus was lower than that of the printed pristine PLA. For 1 wt% flour content, the NFRCs’ maximum stress and strain to failure were higher than those of the printed PLA, which was attributed to the henequen fibers acting as reinforcement and delaying crack growth. However, for 2 wt% and higher flour contents, the NFRCs’ maximum stress was lower than that of the printed PLA. Microscopic characterization after testing showed an increase in voids and defects, with the increase in flour content attributed to particle agglomeration. For 1 wt% flour content, the NFRCs were also printed with raster angles of ±45° and 90° for comparison; the highest tensile properties were obtained with a 0° raster angle. Finally, adding 3 wt% content of maleic anhydride to the NFRC with 1 wt% flour content slightly increased the maximum stress. The results presented herein warrant further research to fully understand the mechanical properties of printed NFRCs made of PLA reinforced with natural henequen fibers. © 2022 by the authors.

POLYLACTIC ACID (PLA) NATURAL FIBER HENEQUEN FIBER NATURAL FIBER REINFORCED COMPOSITE (NFRC) ADDITIVE MANUFACTURING 3D PRINTING MECHANICAL PROPERTY INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE MATERIALES PROPIEDADES DE LOS MATERIALES PROPIEDADES DE LOS MATERIALES

Potential impact of prosthetic biomaterials on the periodontium: a comprehensive review.

NATIVIDAD CASTRO ALARCON Artak Heboyan Gustavo Fernandes Norma Samanta Romero Castro (2023, [Artículo])

The success of a prosthetic treatment is closely related to the periodontal health of the individual. The aim of this article was to review and present the importance of prosthetic restorative materials on the condition of the periodontium, the changes that occur in the composition of the subgingival microbiota and the levels of inflammatory markers in gingival crevicular fluid. Articles on the influence of different prosthetic restorative materials on subgingival microbiota and proinflammatory cytokines were searched for using the keywords ¿prosthetic biomaterials¿, ¿fixed prosthesis¿, ¿periodontal health¿, ¿subgingival microbiota¿, ¿periodontal biomarkers¿ and ¿gingival crevicular fluid¿ in PubMed/Medline, Science Direct, Scopus and Google Scholar. The type of material used for prosthesis fabrication together with poor marginal and internal fit can result in changes in the composition of the subgingival microbiota, as well as increased accumulation and retention of dentobacterial plaque, thus favoring the development of periodontal disease and prosthetic treatment failure. Biological markers have helped to understand the inflammatory response of different prosthetic materials on periodontal tissues with the main purpose of improving their clinical application

in patients who need them. Metal-free ceramic prostheses induce a lower inflammatory response regardless of the fabrication method; however, the use of CAD/CAM systems is recommended for their fabrication. In addition, it is presumed that metal-ceramic prostheses cause changes in the composition of the subgingival microbiota producing a more dysbiotic biofilm with a higher prevalence of periodontopathogenic bacteria, which may further favor periodontal deterioration.

prosthetic biomaterials fixed prosthesis periodontal health MEDICINA Y CIENCIAS DE LA SALUD CIENCIAS MÉDICAS SALUD PÚBLICA