Non-closure of peritoneal surfaces at caesarean section - a systematic review

Background. Caesarean section (CS) is a very common surgical procedure  worldwide. Suturing the peritoneal layers at CS may or may not confer  benefit, hence the need to evaluate whether this step should be omitted or not.Objectives. To assess the effects of non-closure as an alternative to  closure of the peritoneum at CS on intraoperative, immediate and later  postoperative, and long-term outcomes.Search strategy. We searched the Cochrane Pregnancy and Childbirth   Group Trials Register (November 2002) and the Cochrane Central   Controlled Trials Register (October 2003).Selection criteria. Randomised controlled trials that compared leaving the visceral and/ or parietal peritoneum unsutured at CS with suturing the peritoneum, in women undergoing elective or emergency CS.Data collection and analysis. Trial quality was assessed and data were extracted by two reviewers.Main results. Nine trials involving 1 811 women were included and  analysed. The methodological quality of the trials was variable. Non-closure of the peritoneum reduced operating time when both layers or one layer was not sutured. For both layers, the operating time was reduced by7.33 minutes (95% confidence interval (CI): -8.43 - -6.24). There was significantly less postoperative fever and reduced postoperative stay in hospital for non-closure of the visceral peritoneum and non-closure of both layers. There were no other statistically significant differences. The tr.end for analgesia requirement and wound infection tended to favour non-closure, while endometritis results were variable. Longterm follow-up in 1 trial showed no significant differences. The power of the latter study to show differences was low.Conclusions. There was improved short-term postoperative outcome if the peritoneum was not closed. Long-term studies following CS are limited, but data from other surgical procedures are reassuring. At present there is noevidence to justify the time taken and cost of peritoneal closure

Assessment of Post Fire Structural Strengths of Normal Strength Concrete Subjected to Cyclic Thermal Loadings

Concrete is a composite construction material consisting basically of a binder, aggregates, water and with or without admixture to modify either or both its physical and chemical properties. The rate at which concrete structures especially buildings are gutted by fire hazards is on the increase and this has adverse effect on the strength, hence, the need to  assess the post fire structural strengths of Normal Strength Concrete(NSC). NSC of grade 50 was produced and cast into specimens of sizes 150mm cubes and 100mm x 100mm x 500mm reinforced concrete beams. The concrete cubes and beams were subjected to elevated cyclic thermal loadings after 7, 14 and 28 days of curing, while the rate of heating was maintained at 1oC/min until the target temperature of (100, 130, 160, 200 and 250)o C where attained and this was maintained for one hour and then allowed to cool at 1oC/min to room temperature of 32oC.         Unstressed Residual Uniaxial Compressive Test (URUCT and Flexural Strength Test (FST) were conducted on the cubes and reinforced concrete beams, respectively. Direct Tensile Strength Test (DTST) was performed on the high yield (460N/mm2) steel reinforcement. The result showed that the residual compressive strengths of concrete cubes decreases with increase thermal loadings. The expected strengths of 0.69 and 0.97 of the 28 days strength for 7 and 14 days respectively were met. The flexural strengths decrease with increase in thermal loadings. The flexural strength of the concrete beams at 28 days of 15.25N/mm2 at thermal loading of 32oC was reduced to 8.16/mm2 at thermal loading of 160oC; while the strength at 14 days of 12.19 N/mm2 at thermal loading of 32oC was reduced to 7.62N/mm2 at thermal loading of 160oC and finally, the strength at 7 days of 10.13N/mm2 at thermal loading of 32oC was reduced to 5.82N/mm2 at thermal loading of 160oC. All the results met the specification for high yield steel of 12% elongation at fracture. It was concluded that within the thermal loading range adopted, the tensile strength of the reinforcement was not impaired beyond the limit specified by the code. Keyword: Normal Strength Concrete, Thermal loadings, Unstressed Residual  Strength Test, Fire hazard

Assessment of Post Fire Structural Strengths of Normal Strength Concrete Subjected to Cyclic Thermal Loadings

Concrete is a composite construction material consisting basically of a binder, aggregates, water and with or without admixture to modify either or both its physical and chemical properties. The rate at which concrete structures especially buildings are gutted by fire hazards is on the increase and this has adverse effect on the strength, hence, the need to assess the post fire structural strengths of Normal Strength Concrete(NSC). NSC of grade 50 was produced and cast into specimens of sizes 150mm cubes and 100mm x 100mm x 500mm reinforced concrete beams. The concrete cubes and beams were subjected to elevated cyclic thermal loadings after 7, 14 and 28 days of curing, while the rate of heating was maintained at 1oC/min until the target temperature of (100, 130, 160, 200 and 250)o C where attained and this was maintained for one hour and then allowed to cool at 1oC/min to room temperature of 32oC. Unstressed Residual Uniaxial Compressive Test (URUCT and Flexural Strength Test (FST) were conducted on the cubes and reinforced concrete beams, respectively. Direct Tensile Strength Test (DTST) was performed on the high yield (460N/mm2) steel reinforcement. The result showed that the residual compressive strengths of concrete cubes decreases with increase thermal loadings. The expected strengths of 0.69 and 0.97 of the 28 days strength for 7 and 14 days respectively were met. The flexural strengths decrease with increase in thermal loadings. The flexural strength of the concrete beams at 28 days of 15.25N/mm2 at thermal loading of 32oC was reduced to 8.16/mm2 at thermal loading of 160oC; while the strength at 14 days of 12.19 N/mm2 at thermal loading of 32oC was reduced to 7.62N/mm2 at thermal loading of 160oC and finally, the strength at 7 days of 10.13N/mm2 at thermal loading of 32oC was reduced to 5.82N/mm2 at thermal loading of 160oC. All the results met the specification for high yield steel of 12% elongation at fracture. It was concluded that within the thermal loading range adopted, the tensile strength of the reinforcement was not impaired beyond the limit specified by the code

Soil contamination in nearby natural areas mirrors that in urban greenspaces worldwide

Soil contamination is one of the main threats to ecosystem health and sustainability. Yet little is known about the extent to which soil contaminants differ between urban greenspaces and natural ecosystems. Here we show that urban greenspaces and adjacent natural areas (i.e., natural/semi-natural ecosystems) shared similar levels of multiple soil contaminants (metal(loid)s, pesticides, microplastics, and antibiotic resistance genes) across the globe. We reveal that human influence explained many forms of soil contamination worldwide. Socio-economic factors were integral to explaining the occurrence of soil contaminants worldwide. We further show that increased levels of multiple soil contaminants were linked with changes in microbial traits including genes associated with environmental stress resistance, nutrient cycling, and pathogenesis. Taken together, our work demonstrates that human-driven soil contamination in nearby natural areas mirrors that in urban greenspaces globally, and highlights that soil contaminants have the potential to cause dire consequences for ecosystem sustainability and human wellbeing

Environmental filtering controls soil biodiversity in wet tropical ecosystems

9 páginas..- 4 figuras.- referencias.- Supplementary data to this article can be found online at https://doi. org/10.1016/j.soilbio.2022.108571The environmental factors controlling soil biodiversity along resource gradients remain poorly understood in wet tropical ecosystems. Aboveground biodiversity is expected to be driven by changes in nutrient availability in these ecosystems, however, much less is known about the importance of nutrient availability in driving soil biodiversity. Here, we combined a cross-continental soil survey across tropical regions with a three decades' field experiment adding nitrogen (N) and phosphorus (P) (100 kg N ha(-1)y(-1) and 100 kg P ha(-1)y(-1)) to Hawai'ian tropical forests with contrasting substrate ages (300 and 4,100,000 years) to investigate the influence of nutrient availability to explain the biodiversity of soil bacteria, fungi, protists, invertebrates and key functional genes. We found that soil biodiversity was driven by soil acidification during long-term pedogenesis and across environmental gradients, rather than by nutrient limitations. In fact, our results showed that experimental N additions caused substantial acidification in soils from Hawai'i. These declines in pH were related to large decreases in soil biodiversity from tropical ecosystems in four continents. Moreover, the microbial activity did not change in response to long-term N and P additions. We concluded that environmental filtering drives the biodiversity of multiple soil organisms, and that the acidification effects associated with N additions can further create substantial undesired net negative effects on overall soil biodiversity in naturally tropical acid soils. This knowledge is integral for the understanding and management of soil biodiversity in tropical ecosystems globally.Supported by a Ramón y Cajal grant (RYC2018-025483-I), a “Ayuda P.P. 2020. Desarrollo Lineas Investigación Propias (UPO), a project from the Spanish Ministry of Science and Innovation (PID2020-115813RA-I00), and a project PAIDI 2020 from the Junta de Andalucía (P20_00879). H.Y.C. is supported by National Natural Science Foundation of China (32101335), China Postdoctoral Science Foundation (2021M690589), Innovation Project of Young Technological Talents in Changchun City (21QC07), and Fundamental Research Funds for the Central Universities (2412021QD014). J.P.V. is thankful to DST and SERB (Science and Engineering Research Board), India for financial support for plant-microbe interaction research. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Peer reviewe

The global distribution and environmental drivers of the soil antibiotic resistome

Background: Little is known about the global distribution and environmental drivers of key microbial functional traits such as antibiotic resistance genes (ARGs). Soils are one of Earth’s largest reservoirs of ARGs, which are integral for soil microbial competition, and have potential implications for plant and human health. Yet, their diversity and global patterns remain poorly described. Here, we analyzed 285 ARGs in soils from 1012 sites across all continents and created the first global atlas with the distributions of topsoil ARGs. Results: We show that ARGs peaked in high latitude cold and boreal forests. Climatic seasonality and mobile genetic elements, associated with the transmission of antibiotic resistance, were also key drivers of their global distribution. Dominant ARGs were mainly related to multidrug resistance genes and efflux pump machineries. We further pinpointed the global hotspots of the diversity and proportions of soil ARGs. Conclusions: Together, our work provides the foundation for a better understanding of the ecology and global distribution of the environmental soil antibiotic resistome.This project received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement 702057 (CLIMIFUN), a Large Research Grant from the British Ecological Society (agreement no. LRA17\1193; MUSGONET), and from the European Research Council (ERC grant agreement no. 647038, BIODESERT). M. D. B. was also supported by a Ramón y Cajal grant (RYC2018-025483-I). M.D-B. also acknowledges support from the Spanish Ministry of Science and Innovation for the I+D+i project PID2020-115813RA-I00 funded by MCIN/AEI/10.13039/501100011033. M.D-B. is also supported by a project of the Fondo Europeo de Desarrollo Regional (FEDER) and the Consejería de Transformación Económica, Industria, Conocimiento y Universidades of the Junta de Andalucía (FEDER Andalucía 2014-2020 Objetivo temático “01 - Refuerzo de la investigación, el desarrollo tecnológico y la innovación”) associated with the research project P20_00879 (ANDABIOMA). FTM acknowledges support from Generalitat Valenciana (CIDEGENT/2018/041). J. Z. H and H. W. H. are financially supported by Australian Research Council (DP210100332). We also thank the project CTM2015-64728-C2-2-R from the Ministry of Science of Spain. C. A. G. and N. E. acknowledge funding by the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, funded by the German Research Foundation (FZT 118). TG was financially supported by Slovenian Research Agency (P4-0107, J4-3098 and J4-4547)

The global contribution of soil mosses to ecosystem services

Soil mosses are among the most widely distributed organisms on land. Experiments and observations suggest that they contribute to terrestrial soil biodiversity and function, yet their ecological contribution to soil has never been assessed globally under natural conditions. Here we conducted the most comprehensive global standardized field study to quantify how soil mosses influence 8 ecosystem services associated with 24 soil biodiversity and functional attributes across wide environmental gradients from all continents. We found that soil mosses are associated with greater carbon sequestration, pool sizes for key nutrients and organic matter decomposition rates but a lower proportion of soil-borne plant pathogens than unvegetated soils. Mosses are especially important for supporting multiple ecosystem services where vascular-plant cover is low. Globally, soil mosses potentially support 6.43 Gt more carbon in the soil layer than do bare soils. The amount of soil carbon associated with mosses is up to six times the annual global carbon emissions from any altered land use globally. The largest positive contribution of mosses to soils occurs under a high cover of mat and turf mosses, in less-productive ecosystems and on sandy and salty soils. Our results highlight the contribution of mosses to soil life and functions and the need to conserve these important organisms to support healthy soils.The study work associated with this paper was funded by a Large Research Grant from the British Ecological Society (no. LRB17\1019; MUSGONET). D.J.E. is supported by the Hermon Slade Foundation. M.D.-B. was supported by a Ramón y Cajal grant from the Spanish Ministry of Science and Innovation (RYC2018-025483-I), a project from the Spanish Ministry of Science and Innovation for the I + D + i (PID2020-115813RA-I00 funded by MCIN/AEI/10.13039/501100011033a) and a project PAIDI 2020 from the Junta de Andalucía (P20_00879). E.G. is supported by the European Research Council grant agreement 647038 (BIODESERT). M.B. is supported by a Ramón y Cajal grant from Spanish Ministry of Science (RYC2021-031797-I). A.d.l.R is supported by the AEI project PID2019-105469RB-C22. L.W. and Jianyong Wang are supported by the Program for Introducing Talents to Universities (B16011) and the Ministry of Education Innovation Team Development Plan (2013-373). The contributions of T.G. and T.U.N. were supported by the Research Program in Forest Biology, Ecology and Technology (P4-0107) and the research projects J4-3098 and J4-4547 of the Slovenian Research Agency. The contribution of P.B.R. was supported by the NSF Biological Integration Institutes grant DBI-2021898. J. Durán and A. Rodríguez acknowledge support from the FCT (2020.03670.CEECIND and SFRH/BDP/108913/2015, respectively), as well as from the MCTES, FSE, UE and the CFE (UIDB/04004/2021) research unit financed by FCT/MCTES through national funds (PIDDAC)

Biogenic factors explain soil carbon in paired urban and natural ecosystems worldwide

12 páginas.- 4 figuras.- 49 referencia.- Supplementary information The online version contains supplementary material available at https://doi.org/10.1038/s41558-023-01646-z .- Full-text access to a view-only version (Acceso a texto completo de sólo lectura en este enlace) https://rdcu.be/c8vZiUrban greenspaces support multiple nature-based services, many of which depend on the amount of soil carbon (C). Yet, the environmental drivers of soil C and its sensitivity to warming are still poorly understood globally. Here we use soil samples from 56 paired urban greenspaces and natural ecosystems worldwide and combine soil C concentration and size fractionation measures with metagenomics and warming incubations. We show that surface soils in urban and natural ecosystems sustain similar C concentrations that follow comparable negative relationships with temperature. Plant productivity’s contribution to explaining soil C was higher in natural ecosystems, while in urban ecosystems, the soil microbial biomass had the greatest explanatory power. Moreover, the soil microbiome supported a faster C mineralization rate with experimental warming in urban greenspaces compared with natural ecosystems. Consequently, urban management strategies should consider the soil microbiome to maintain soil C and related ecosystem services.This study was supported by a 2019 Leonardo Grant for Researchers and Cultural Creators, BBVA Foundation (URBANFUN), and by BES Grant Agreement No. LRB17\1019 (MUSGONET). M.D-B., P.G-P., J.D. and A.R. acknowledge support from TED2021-130908B-C41/AEI/10.13039/501100011033/ Unión Europea NextGenerationEU/PRTR. M.D.-B. also acknowledges support from the Spanish Ministry of Science and Innovation for the I + D + i project PID2020-115813RA-I00 funded by MCIN/AEI/10.13039/501100011033. M.D.-B. was also supported by a project of the Fondo Europeo de Desarrollo Regional (FEDER) and the Consejería de Transformación Económica, Industria, Conocimiento y Universidades of the Junta de Andalucía (FEDER Andalucía 2014-2020 Objetivo temático ‘01 - Refuerzo de la investigación, el desarrollo tecnológico y la innovación’) associated with the research project P20_00879 (ANDABIOMA). D.J.E. was supported by the Hermon Slade Foundation. J.P.V. thanks the Science and Engineering Research Board (SERB) (EEQ/2021/001083, SIR/2022/000626) and the Department of Science and Technology (DST), India (DST/INT/SL/P-31/2021) and Banaras Hindu Univeristy-IoE (6031)-incentive grant for financial assistance for research in plant-microbe interaction and soil microbiome. J.D. and A. Rodríguez acknowledge support from the FCT (2020.03670.CEECIND and SFRH/BDP/108913/2015, respectively), as well as from the MCTES, FSE, UE and the CFE (UIDB/04004/2021) research unit financed by FCT/MCTES through national funds (PIDDAC).Peer reviewe

Global hotspots for soil nature conservation

19 páginas.- 5 figuras.- 98 referencias.- Supplementary information The online version contains supplementary material available at https://doi.org/10.1038/s41586-022-05292-xSoils are the foundation of all terrestrial ecosystems1. However, unlike for plants and animals, a global assessment of hotspots for soil nature conservation is still lacking2. This hampers our ability to establish nature conservation priorities for the multiple dimensions that support the soil system: from soil biodiversity to ecosystem services. Here, to identify global hotspots for soil nature conservation, we performed a global field survey that includes observations of biodiversity (archaea, bacteria, fungi, protists and invertebrates) and functions (critical for six ecosystem services) in 615 composite samples of topsoil from a standardized survey in all continents. We found that each of the different ecological dimensions of soils—that is, species richness (alpha diversity, measured as amplicon sequence variants), community dissimilarity and ecosystem services—peaked in contrasting regions of the planet, and were associated with different environmental factors. Temperate ecosystems showed the highest species richness, whereas community dissimilarity peaked in the tropics, and colder high-latitudinal ecosystems were identified as hotspots of ecosystem services. These findings highlight the complexities that are involved in simultaneously protecting multiple ecological dimensions of soil. We further show that most of these hotspots are not adequately covered by protected areas (more than 70%), and are vulnerable in the context of several scenarios of global change. Our global estimation of priorities for soil nature conservation highlights the importance of accounting for the multidimensionality of soil biodiversity and ecosystem services to conserve soils for future generations.This project received funding from the British Ecological Society (agreement LRA17\1193; MUSGONET). C.A.G. and N.E. were funded by DFG–FZT 118, 202548816; C.A.G. was supported by FCT-PTDC/BIA-CBI/2340/2020; M.D.-B. was supported by RYC2018-025483-I, PID2020-115813RA-I00\MCIN/AEI/10.13039/501100011033 and P20_00879. M.A.M.-M. and S.A. were funded by FONDECYT 1181034 and ANID-PIA-Anillo INACH ACT192057. J.D. and A.R. acknowledge support from IF/00950/2014, 2020.03670.CEECIND, SFRH/BDP/108913/2015 and UIDB/04004/2020. Y.-R.L. was supported by 2662019PY010 from the FRFCU. L.T. was supported by the ESF grant PRG632. F.B. and J.L.M. were supported by i-LINK+2018 (LINKA20069) funded by CSIC. C.T.-D. was supported by the Grupo de Biodibersidad & Cambio Global UBB–GI 170509/EF. C.P. was supported by the EU H2020 grant agreement 101000224. H.C. was supported by NSFC32101335, FRFCU2412021QD014 and CPSF2021M690589. J.P.V. was supported by DST (DST/INT/SL/P-31/2021) SERB (EEQ/2021/001083) and BHU-IoE (6031).Peer reviewe