RESUMEN
As a transition zone between the terrestrial ecosystem and the marine ecosystem, coastal intertidal wetland provides an important place for material circulation and energy exchange, and it is nature's most precious resource. The ecological health of intertidal wetlands is an important prerequisite for sustainable green development. The material exchange function objectively and accurately reflects the material balance and ecological health of intertidal wetlands in the coastal zone. This paper uses remote sensing, geographic information technology, and model methods to objectively and accurately assess the temporal and spatial changes in the material exchange function of intertidal wetlands, providing a feasible method for studying the material exchange function of coastal wetlands. The material exchange capacity of wetlands in intertidal zones is affected by many factors, such as vegetation, topography, and base soil. After the invasion of the alien species Spartina alterniflora Lois., the elevation of the Suaeda salsa beach increased by 0.3 m. The elevation of the Phragmites australis beach rose by 0.14 m. The average elevation of S. alterniflora increased by 1.24 m. The material exchange capacity of the intertidal zone decreased by 25%. The functioning of the material exchange between sea and land changed significantly, and the area with a high level of material exchange function capacity was reduced by 71%.
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Ecosistema , Humedales , China , Especies Introducidas , Poaceae , SueloRESUMEN
India is home to 1.3 billion people who are exposed to some of the highest levels of ambient air pollution in the world. In addition, India is one of the fastest-growing carbon-emitting countries. Here, we assess how two strategies to reuse waste-heat from coal-fired power plants and other large sources would impact PM2.5-air quality, human health, and CO2 emissions in 2015 and a future year, 2050, using varying levels of policy adoption (current regulations, proposed single-sector policies, and ambitious single-sector strategies). We find that power plant and industrial waste-heat reuse as input to district heating systems (DHSs), a novel, multisector strategy to reduce local biomass burning for heating emissions, can offset 71.3-85.2% of residential heating demand in communities near a power plant (9.3-12.4% of the nationwide heating demand) with the highest benefits observed during winter months in areas with collocated industrial activity and higher residential heating demands (e.g., New Delhi). Utilizing waste-heat to generate electricity via organic Rankine cycles (ORCs) can generate an additional 22 (11% of total coal-fired generating capacity), 41 (8%), 32 (13%), and 6 (5%) GW of electricity capacity in the 2015, 2050-current regulations, 2050-single-sector, and 2050-ambitious-single-sector scenarios, respectively. Emission estimates utilizing these strategies were input to the GEOS-Chem model, and population-weighted, simulated PM2.5 showed small improvements in the DHS (0.2-0.4%) and ORC (0.3-3.4%) scenarios, where the minimal DHS PM2.5-benefit is attributed to the small contribution of biomass burning for heating to nationwide PM2.5 emissions (much of the biomass burning activity is for cooking). The PM2.5 reductions lead to â¼130-36,000 mortalities per year avoided among the scenarios, with the largest health benefits observed in the ORC scenarios. Nationwide CO2 emissions reduced <0.04% by DHSs but showed larger reductions using ORCs (1.9-7.4%). Coal fly-ash as material exchange in cement and brick production was assessed, and capacity exists to completely reutilize unused fly-ash toward cement and brick production in each of the scenarios.
Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Dióxido de Carbono , China , Carbón Mineral , Ceniza del Carbón , Calor , Humanos , Material Particulado/análisisRESUMEN
The emergence of a reaction cycle in a mixture of reacting molecules may require naturalized regulation of the constituent material elements. One source of naturalized regulation could be sought in updating the constituent elements through exchanging with those available from the outside under the conditions of unidirectional heat flow. One physical vehicle for implementing constant material exchange could be a durable reaction cycle serving as a necessary precursor to the phenomenon called life. Each constituent element circulating around a durable reaction cycle moves causally until it comes to eventually leave the cycle. At the same time, the circulation is also retrocausal in letting the reaction flow in the downstream pull in and being cohesive to those reactants in the immediate upstream. The onset of a reaction cycle as a precursor to the origins of life must have corresponded to a unique historical event taking advantage of the likelihood of retrocausal cohesion propagating backward along the reaction sequence. Physical underpinning of biology may be found in the operation of retrocausal cohesion.
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Ciclo del Ácido Cítrico , Modelos Biológicos , Biología de Sistemas , Animales , Humanos , Tiempo de Reacción , Biología de Sistemas/métodosRESUMEN
Some types of cells, if not all, that undergo signal exchanges in culture need to contact other cells for various reasons, such as cell-to-cell contact for growth inhibition. However, signal exchanges by cell-to-cell contact before proliferation have never been reported. Using time-lapse recording, we discovered the emergence of several astonishing cell-to-cell contact modes in bone marrow-derived mesenchymal stem/stromal cells (MSCs) before the cells divided. When the cells contacted with another, a huge temporary synapse-like structure formed for molecule exchanges; a cell-tissue particle was taken in by a recipient cell; two cell membranes formed infusion-like structure for a short time; and even a 20-µm long and 5-µm wide cell tail was grafted to another cell. A total of 87% of cells underwent cell-to-cell contact before dividing. After epidermal growth factor-green fluorescent protein (EGF-GFP) vectors were transfected into MSCs and the cells were cocultured with unmanipulated MSCs, the unmanipulated MSCs took in EGF-GFP particles from EGF-GFP expressed MSCs, immediately increased in mitogen genes, and then divided. These results suggest that cells which may lack signal molecules may need to obtain these molecules from other cells through various types of cell-to-cell contact, as mentioned above. Our study provided valuable information to better understand the behaviors of cell-to-cell contact and communication before mitosis.
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Células de la Médula Ósea/fisiología , Comunicación Celular , Células Madre Mesenquimatosas/fisiología , Transducción de Señal , Adulto , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Células Cultivadas , Factor de Crecimiento Epidérmico/genética , Factor de Crecimiento Epidérmico/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , MitosisRESUMEN
Considerable research effort has been invested into the transplantation of mammalian photoreceptors into healthy and degenerating mouse eyes. Several platforms of rod and cone fluorescent reporting have been central to refining the isolation, purification and transplantation of photoreceptors. The tracking of engrafted cells, including identifying the position, morphology and degree of donor cell integration post-transplant is highly dependent on the use of fluorescent protein reporters. Improvements in imaging and analysis of transplant recipients have revealed that donor cell fluorescent reporters can transfer into host tissue though a process termed material exchange (ME). This recent discovery has chaperoned a new era of interpretation when reviewing the field's use of dissociated donor cell preparations, and has prompted scientists to re-examine how we use and interpret the information derived from fluorescence-based tracking tools. In this review, we describe the status of our understanding of ME in photoreceptor transplantation. In addition, we discuss the impact of this discovery on several aspects of historical rod and cone transplantation data, and provide insight into future standards and approaches to advance the field of cell engraftment.
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Células Fotorreceptoras Retinianas Conos/trasplante , Animales , Comunicación Celular , Humanos , Células Fotorreceptoras Retinianas Conos/citología , Células Fotorreceptoras Retinianas Conos/fisiología , Degeneración Retiniana/diagnóstico por imagen , Degeneración Retiniana/fisiopatología , Degeneración Retiniana/terapiaRESUMEN
Staphylococcus epidermidis has been suggested as a main reservoir of methicillin resistance and virulence genes facilitating the evolution of Staphylococcus aureus as a successful pathogen. However, it remains a mystery where and how S. epidermidis obtains these numerous genes to serve as the reservoir. In this study, methicillin-resistant S. epidermidis isolate NW32 from a mastitic milk sample was sequenced and its staphylococcal cassette chromosome (SCC) elements were characterised. The SCC composite island covered 3.5% of the genome and consisted of three intact SCC elements carrying resistance genes against ß-lactam antibiotics, several heavy metals and polyamines as well as genes for utilisation of sorbitol as a carbon source. Analysis of the postulated evolutionary route suggested that the three SCC elements were assembled from genetic material from various bacterial species (staphylococci, streptococci, salinicocci and Lysinibacillus) from three habitats (human, soil and cow) in different countries (Asia, North America, South America and Europe). We propose that the hsdS restriction-modification profile and the lack of CRISPR (clustered regularly interspaced short palindromic repeat) sequences in this bacterium may facilitate the genetic exchange of SCC elements among different staphylococcal species.