ABSTRACT
Since the 1950's, global fertilizer usage has increased by more than 800% resulting in detrimental impacts to the environment. The projected increase in crop production due to increasing demands for food, feed, biofuel, and other uses, may further increase fertilizer usage. Studies have examined achieving agricultural intensification in environmentally sustainable ways, however, they have not focused on the whole-system economic aspects of changes in fertilizer usage over the long term. We utilize the Global Change Analysis Model (GCAM) to explore the impact of reducing global fertilizer usage on land use change, agricultural commodity price and production, energy production, and greenhouse gas emissions. We find that constrained fertilizer availability results in reduced global cropland area, particularly land used for bioenergy production, and expanded forested area. These results are driven by price impacts which lead to shifts in agricultural production between commodity types, regions, and technologies, and which lead to decreased agricultural commodity demands.
Subject(s)
Fertilizers , Greenhouse Gases , Agriculture , Biofuels , Fertilizers/analysis , ForestsABSTRACT
There is evidence that warming leads to greater evapotranspiration and surface drying, thus contributing to increasing intensity and duration of drought and implying that mitigation would reduce water stresses. However, understanding the overall impact of climate change mitigation on water resources requires accounting for the second part of the equation, i.e., the impact of mitigation-induced changes in water demands from human activities. By using integrated, high-resolution models of human and natural system processes to understand potential synergies and/or constraints within the climate-energy-water nexus, we show that in the United States, over the course of the 21st century and under one set of consistent socioeconomics, the reductions in water stress from slower rates of climate change resulting from emission mitigation are overwhelmed by the increased water stress from the emissions mitigation itself. The finding that the human dimension outpaces the benefits from mitigating climate change is contradictory to the general perception that climate change mitigation improves water conditions. This research shows the potential for unintended and negative consequences of climate change mitigation.
Subject(s)
Climate Change , Conservation of Natural Resources/methods , Public Policy , Water Supply , Forecasting , Fresh Water , Global Warming , Groundwater , Models, Theoretical , Socioeconomic Factors , United States , Water CycleABSTRACT
Despite significant effort to quantify the interdependence of the water and energy sectors, global requirements of energy for water (E4W) are still poorly understood, which may result in biases in projections and consequently in water and energy management and policy. This study estimates water-related energy consumption by water source, sector, and process for 14 global regions from 1973 to 2012. Globally, E4W amounted to 10.2 EJ of primary energy consumption in 2010, accounting for 1.7%-2.7% of total global primary energy consumption, of which 58% pertains to fresh surface water, 30% to fresh groundwater, and 12% to nonfresh water, assuming median energy intensity levels. The sectoral E4W allocation includes municipal (45%), industrial (30%), and agricultural (25%), and main process-level contributions are from source/conveyance (39%), water purification (27%), water distribution (12%), and wastewater treatment (18%). While the United States was the largest E4W consumer from the 1970s until the 2000s, the largest consumers at present are the Middle East, India, and China, driven by rapid growth in desalination, groundwater-based irrigation, and industrial and municipal water use, respectively. The improved understanding of global E4W will enable enhanced consistency of both water and energy representations in integrated assessment models.
Subject(s)
Water Purification , Water , Fresh Water , Groundwater , Water SupplyABSTRACT
In recent years, there has been significant research interest in carbon-based nanomaterials as promising candidates for sensing technologies. Herein, we present the first utilization of asphaltenes as an affordable, cost-efficient carbon-based material for gas sensing applications. Asphaltenes, derived from various oil sources, are subjected to facile cross-linking reactions to produce nanoporous carbon materials, where the asphaltene molecules from different layers are interconnected via covalent bonds. The characterization results of these cross-linked asphaltenes revealed substantial enhancement in their specific surface area and surface functionality. Quartz crystal microbalance sensors with sensing films derived from various asphaltene samples were prepared to detect different ethanol concentrations at room temperature. All the cross-linked asphaltene samples showed a significant enhancement in the sensing response (up to 430%) compared to that of their respective raw parent samples. Such a response of the cross-linked asphaltene samples was comparable to that obtained from graphene oxide. The sensor based on cross-linked asphaltenes demonstrated good linearity, with a response time of approximately 2.4 min, a recovery time of around 8 min, and an excellent response repeatability. After 30 days, the sensor based on cross-linked asphaltenes showed approximately 40% reduction in its response, suggesting long-term aging. This decline is partially attributed to the observed swelling. The current study opens the door to a deeper exploration of asphaltenes and highlights their potential as promising candidates for sensing applications.
ABSTRACT
Acute lymphoblastic leukemia (ALL) is the most common malignancy in children and relapsed B-ALL is the leading cause of mortality in children with leukemia due to a lack of response to treatment. S100A8 is a low molecular weight calcium-binding intracellular protein that is expressed in certain cells, and its increased expression is seen in most tumors as well as in relapsed childhood B-ALL cases. The present study indicates the important role of S100A8 in improving viability and resistance to chemotherapy in relapsed B-ALL lymphoblasts. S100A8 levels were compared in B-ALL and relapsed B-ALL lymphoblasts that were sensitive and resistant to Vincristine, respectively. S100A8 was inhibited in the lymphoblasts of two patients by antisense locked nucleic acid (LNA) GapmeRs and the decreased expression of S100A8 was evaluated using quantitative real-time PCR and ELISA. Then, the S100A8 antisense LNA GapmeRs-transfected cells were treated with Vincristine and the expression levels of S100A8 mRNA and S100A8 protein were re-determined. At all of these stages, cell viability and LC50 were assessed by MTT assay. The results showed that S100A8 levels in relapsed B-ALL lymphoblasts were significantly higher than B-ALL lymphoblasts. Moreover, the increase in S100A8 expression was proportionate to the increase in Vincristine resistance in these cells. The S100A8 knockdown procedure using antisense LNA GapmeRs decreased the cell viability and increased vincristine sensitivity in lymphoblasts of two patients, and it also increased the sensitivity to chemotherapy in relapsed B-ALL lymphoblasts. According to the findings of the present study, S100A8 is effective in developing lymphoblast resistance to chemotherapy, and its enhanced expression may contribute to shifting B-ALL into the relapse phase of the illness. As a result, S100A8 may be a valuable target for managing and improving relapses B-ALL.
Subject(s)
Calgranulin A , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Calgranulin A/antagonists & inhibitors , Calgranulin A/genetics , Child , Humans , Lymphocytes/pathology , Oligonucleotides , Oligonucleotides, Antisense , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Recurrence , Vincristine/pharmacologyABSTRACT
Introduction: Exosomal microRNAs (miRNAs) are emerging diagnostic biomarkers for different types of cancers. We aim to detect gastric cancer (GC)-specific miRNAs in serum exosomes with diagnostic potential. Methods: A pair of 43 tumor and tumor-adjacent tissue biopsies obtained from GC patients, also 5 mL peripheral blood (following 12h fasting) were collected from the same patients and healthy controls (HCs). QIAGEN miRCURY LNA miRNA Focus PCR Panel applied to screen differentially expressed onco-miRNAs. The candidate miRNAs with the highest fold changes proceeded for validation by qRT-PCR in individuals. Results: We identified that exosomal miR-10a-5p, miR-19b-3p, miR-215-5p, and miR-18a-5p were significantly upregulated in GC patient's exosomes in contrast to HCs exosomes, Roc curve analysis indicated area under the ROC curve (AUC) of 0.801, 0.721, 0.780 and 0.736 respectively. The Roc curve analysis for the combined signature of four exosomal miRNAs indicated AUC of 0.813. Also, Spearman's correlation coefficients indicated that the miRNA expression is highly correlated between tumor and exosome. Conclusion: Herein, we specifically identified four miRNAs in serum exosomes of GC patients for a diagnostic purpose which are directly associated with tumoral miRNA expression profile.
ABSTRACT
Water scarcity is dynamic and complex, emerging from the combined influences of climate change, basin-level water resources, and managed systems' adaptive capacities. Beyond geophysical stressors and responses, it is critical to also consider how multi-sector, multi-scale economic teleconnections mitigate or exacerbate water shortages. Here, we contribute a global-to-basin-scale exploratory analysis of potential water scarcity impacts by linking a global human-Earth system model, a global hydrologic model, and a metric for the loss of economic surplus due to resource shortages. We find that, dependent on scenario assumptions, major hydrologic basins can experience strongly positive or strongly negative economic impacts due to global trade dynamics and market adaptations to regional scarcity. In many cases, market adaptation profoundly magnifies economic uncertainty relative to hydrologic uncertainty. Our analysis finds that impactful scenarios are often combinations of standard scenarios, showcasing that planners cannot presume drivers of uncertainty in complex adaptive systems.
ABSTRACT
Governance measures such as restrictions on groundwater pumping and adjustments to sectoral water pricing have been suggested as response strategies to curtail recent increases in groundwater pumping and enhance sustainable water use. However, little is known about the impacts of such sustainability strategies. We investigate the implications of such measures, with the United States (U.S.) as an example. Using the Global Change Analysis Model (GCAM) with state-level details in the U.S., we find that the combination of these two governance measures can drastically alter agricultural production in the U.S. The Southwest stands to lose upwards of 25% of their total agricultural production, much of which is compensated for by production increases in river basins on the east coast of the U.S. The implementation of future sustainable water governance measures will require additional investments that allow farmers to maximize production while minimizing water withdrawals to avoid potentially detrimental revenue losses.
ABSTRACT
Long-term temperature change and variability are expected to have significant impacts on future electric capacity and investments. This study improves upon past studies by accounting for hourly and monthly dynamics of electricity use, long-term socioeconomic drivers, and interactions of the electric sector with rest of the economy for a comprehensive analysis of temperature change impacts on cooling and heating services and their corresponding impact on electric capacity and investments. Using the United States as an example, here we show that under a scenario consistent with a socioeconomic pathway 2 (SSP2) and representative concentration pathway 8.5 (RCP 8.5), mean temperature changes drive increases in annual electricity demands by 0.5-8% across states in 2100. But more importantly, peak temperature changes drive increases in capital investments by 3-22%. Moreover, temperature-induced capital investments are highly sensitive to both long-term socioeconomic assumptions and spatial heterogeneity of fuel prices and capital stock characteristics, which underscores the importance of a comprehensive approach to inform long-term electric sector planning.
ABSTRACT
Climate change mitigation will require substantial investments in renewables. In addition, climate change will affect future renewable supply and hence, power sector investment requirements. We study the implications of climate impacts on renewables for power sector investments under deep decarbonization using a global integrated assessment model. We focus on Latin American and Caribbean, an under-studied region but of great interest due to its strong role in international climate mitigation and vulnerability to climate change. We find that accounting for climate impacts on renewables results in significant additional investments ($12-114 billion by 2100 across Latin American countries) for a region with weak financial infrastructure. We also demonstrate that accounting for climate impacts only on hydropower-a primary focus of previous studies-significantly underestimates cumulative investments, particularly in scenarios with high intermittent renewable deployment. Our study underscores the importance of comprehensive analyses of climate impacts on renewables for improved energy planning.
ABSTRACT
Water stressed regions rely heavily on the import of water-intensive goods to offset insufficient food production driven by socioeconomic and environmental factors. The water embedded in these traded commodities, virtual water, has received increasing interest in the scientific community. However, comprehensive future projections of virtual water trading remain absent. Here we show, for the first time, changes over the 21st century in the amount of various water types required to meet international agricultural demands. Accounting for evolution in socioeconomic and climatic conditions, we estimate future interregional virtual water trading and find trading of renewable water sources may triple by 2100 while nonrenewable groundwater trading may at least double. Basins in North America, and the La Plata and Nile Rivers are found to contribute extensively to virtual water exports, while much of Africa, India, and the Middle East relies heavily on virtual water imports by the end of the century.
ABSTRACT
Global future land use (LU) is an important input for Earth system models for projecting Earth system dynamics and is critical for many modeling studies on future global change. Here we generated a new global gridded LU dataset using the Global Change Analysis Model (GCAM) and a land use spatial downscaling model, named Demeter, under the five Shared Socioeconomic Pathways (SSPs) and four Representative Concentration Pathways (RCPs) scenarios. Compared to existing similar datasets, the presented dataset has a higher spatial resolution (0.05° × 0.05°) and spreads under a more comprehensive set of SSP-RCP scenarios (in total 15 scenarios), and considers uncertainties from the forcing climates. We compared our dataset with the Land Use Harmonization version 2 (LUH2) dataset and found our results are in general spatially consistent with LUH2. The presented dataset will be useful for global Earth system modeling studies, especially for the analysis of the impacts of land use and land cover change and socioeconomics, as well as the characterizing the uncertainties associated with these impacts.
ABSTRACT
Many of the world's major freshwater aquifers are being exploited unsustainably, with some projected to approach environmentally unsafe drawdown limits within the 21st century. Given that aquifer depletion tends to occur in important crop producing regions, the prospect of running dry poses a significant threat to global food security. Here we use the Global Change Assessment Model (GCAM) to explore the response of land use and agriculture sectors to severe constraints on global water resources. We simulate a scenario in which a number of important groundwater aquifers become depleted to the point where further water withdrawal is unviable, either due to excessive extraction costs or environmental limits being reached. Results are then benchmarked against a scenario that neglects constraints on water withdrawals. We find that groundwater depletion and associated water price increases drive two distinct responses in the agriculture sector: an expansion of rain fed agriculture, and a shift in irrigated crop production toward regions with cheaper water resources. Losses in crop production are most pronounced in water stressed regions where groundwater is being depleted unsustainably to meet irrigation demands-namely northwest India, Pakistan, the Middle East, western United States, Mexico, and Central Asia. While these results highlight substantial risks for the affected regional agricultural economies, we show that modest changes in irrigation and location of crop growth, in a world with frictionless trade, could ensure global food demands are met despite severe water constraints.
ABSTRACT
In the 2015 Paris Agreement, nations worldwide pledged emissions reductions (Nationally Determined Contributions-NDCs) to avert the threat of climate change, and agreed to periodically review these pledges to strengthen their level of ambition. Previous studies have analyzed NDCs largely in terms of their implied contribution to limit global warming, their implications on the energy sector or on mitigation costs. Nevertheless, a gap in the literature exists regarding the understanding of implications of the NDCs on countries' Energy-Water-Land nexus resource systems. The present paper explores this angle within the regional context of Latin America by employing the Global Change Assessment Model, a state-of-the-art integrated assessment model capable of representing key system-wide interactions among nexus sectors and mitigation policies. By focusing on Brazil, Mexico, Argentina and Colombia, we stress potential implications on national-level water demands depending on countries' strategies to enforce energy-related emissions reductions and their interplays with the land sector. Despite the differential implications of the Paris pledges on each country, increased water demands for crop and biomass irrigation and for electricity generation stand out as potential trade-offs that may emerge under the NDC policy. Hence, this study underscores the need of considering a nexus resource planning framework (known as "Nexus Approach") in the forthcoming NDCs updating cycles as a mean to contribute toward sustainable development.
Subject(s)
Environmental Policy , Global Warming , Greenhouse Effect , Water Resources , Argentina , Brazil , Colombia , Greenhouse Gases , Latin America , MexicoABSTRACT
A rapid and deep decarbonization of power supply worldwide is required to limit global warming to well below 2 °C. Beyond greenhouse gas emissions, the power sector is also responsible for numerous other environmental impacts. Here we combine scenarios from integrated assessment models with a forward-looking life-cycle assessment to explore how alternative technology choices in power sector decarbonization pathways compare in terms of non-climate environmental impacts at the system level. While all decarbonization pathways yield major environmental co-benefits, we find that the scale of co-benefits as well as profiles of adverse side-effects depend strongly on technology choice. Mitigation scenarios focusing on wind and solar power are more effective in reducing human health impacts compared to those with low renewable energy, while inducing a more pronounced shift away from fossil and toward mineral resource depletion. Conversely, non-climate ecosystem damages are highly uncertain but tend to increase, chiefly due to land requirements for bioenergy.
Subject(s)
Air Pollution/prevention & control , Carbon Dioxide/antagonists & inhibitors , Ecosystem , Greenhouse Gases/antagonists & inhibitors , Renewable Energy , Air Pollution/analysis , Carbon Dioxide/analysis , Electric Power Supplies , Global Warming , Greenhouse Effect , Greenhouse Gases/analysis , HumansABSTRACT
BACKGROUND: During laparoscopy, insufflation of an inert gas in the peritoneal cavity creates a working space to facilitate surgery. The space should be large enough to facilitate surgery without increasing intra-abdominal pressure (IAP) over a threshold limit (usually 15 mm Hg). OBJECTIVES: This experimental study was performed to evaluate the effects of increasing in intra-abdominal pressure on internal organs. MATERIALS AND METHODS: Twenty female mixed breed dogs (20 ± 3 kg, 18 ± 1.2 months) were selected. They were randomly divided to two groups (n = 10). The intra-abdominal pressure was maintained 12 mm Hg and 20 mm Hg during the operation in control group and in test group respectively. RESULTS: Histopathologic evaluations revealed more pathological changes at the kidney of all the dogs in test group in comparison to control group. CONCLUSIONS: Our findings revealed that organs that their blood supplies are related to one single or two arteries and their blood drainage are related to one or two veins are more sensitive to increased intra-abdominal pressure.
ABSTRACT
In nail split, the nail plate is divided into two parts. Trauma involving the nail matrix, the generator of the nail plate, can result in nail plate splitting which may take some months to become apparent. Photographic documentation of this condition in the literature had hitherto been lacking.