scholarly journals Variability in historical emissions trends suggests a need for a wide range of global scenarios and regional analyses

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Jiesper Strandsbjerg Tristan Pedersen ◽  
Detlef P. van Vuuren ◽  
Bruno A. Aparício ◽  
Rob Swart ◽  
Joyeeta Gupta ◽  
...  
Keyword(s):  
Carbon Dioxide Emissions ◽  
Emission Scenario ◽  
Future Climate Change ◽  
Emission Scenarios ◽  
The Past ◽  
Wide Range ◽  
High Emission ◽  
Regional Analyses ◽  
Global Emissions

AbstractLong-term developments in carbon dioxide emissions have tracked the middle of projected emission scenario ranges over the past three decades. If this tendency continues, it seems increasingly less likely that future emissions will follow current high-emission scenarios. However, in the past, periods of slow and fast global emissions growth was observed, which have led to previous critiques of scenarios being too low or too high. In the light of such unpredictability and since scenarios are meant to explore plausible futures, we here argue that a broad range of emission scenarios continue to be considered input in scenario-based analyses of future climate change. Furthermore, we find substantial regional differences in emissions trends. Territorial emissions in OECD countries fall on the low side of emission scenario ranges, whereas non-OECD territorial emissions fell closer to the medium or high-end. Since non-OECD emissions will become increasingly important, we recommend further exploring the relationships between regional and global emissions to support scenario assumptions and climate policymaking.

Chinese Medicine Protein and Peptide in Gene and Cell Therapy

2019 ◽  
Vol 20 (3) ◽  
pp. 251-264 ◽  
Author(s):  
Yinlu Feng ◽  
Zifei Yin ◽  
Daniel Zhang ◽  
Arun Srivastava ◽  
Chen Ling
Keyword(s):  
Chinese Medicine ◽  
Cell Therapy ◽  
Future Research ◽  
The Past ◽  
Promising Strategy ◽  
Wide Range ◽  
New Directions ◽  
Gene And Cell Therapy ◽  
Proteins And Peptides

The success of gene and cell therapy in clinic during the past two decades as well as our expanding ability to manipulate these biomaterials are leading to new therapeutic options for a wide range of inherited and acquired diseases. Combining conventional therapies with this emerging field is a promising strategy to treat those previously-thought untreatable diseases. Traditional Chinese medicine (TCM) has evolved for thousands of years in China and still plays an important role in human health. As part of the active ingredients of TCM, proteins and peptides have attracted long-term enthusiasm of researchers. More recently, they have been utilized in gene and cell therapy, resulting in promising novel strategies to treat both cancer and non-cancer diseases. This manuscript presents a critical review on this field, accompanied with perspectives on the challenges and new directions for future research in this emerging frontier.

Cognitive impairment in long-term benzodiazepine users

1988 ◽  
Vol 18 (2) ◽  
pp. 365-374 ◽  
Author(s):  
Susan Golombok ◽  
Parimala Moodley ◽  
Malcolm Lader
Keyword(s):  
Neuropsychological Tests ◽  
Matched Control ◽  
Control Group ◽  
Therapeutic Practice ◽  
The Past ◽  
Visual Spatial ◽  
Wide Range ◽  
High Doses ◽  
One Year

SynopsisIn view of the very extensive and often prolonged use of benzodiazepines in therapeutic practice, this study was designed to investigate whether or not cognitive ability is impaired in longterm benzodiazepine users, and to determine the nature and extent of any deficit. Fifty patients currently taking benzodiazepines for at least one year, thirty-four who had stopped taking benzodiazepines, and a matched control group of subjects who had never taken benzodiazepines or who had taken benzodiazepines in the past for less than one year were administered a battery of neuropsychological tests designed to measure a wide range of cognitive functions. It was found that patients taking high doses of benzodiazepines for long periods of time perform poorly on tasks involving visual-spatial ability and sustained attention. This is consistent with deficits in posterior cortical cognitive function.

scholarly journals Drought Risk under Climate and Land Use Changes: Implication to Water Resource Availability at Catchment Scale

Water ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1790 ◽  
Author(s):  
Muhammad Afzal ◽  
Ragab Ragab
Keyword(s):  
Climate Change ◽  
Land Use ◽  
Water Resources ◽  
Groundwater Recharge ◽  
Land Use Changes ◽  
Future Climate Change ◽  
Emission Scenarios ◽  
Catchment Scale ◽  
High Emission ◽  
The Impact

Although the climate change projections are produced by global models, studying the impact of climatic change on water resources is commonly investigated at catchment scale where the measurements are taken, and water management decisions are made. For this study, the Frome catchment in the UK was investigated as an example of midland England. The DiCaSM model was applied using the UKCP09 future climate change scenarios. The climate projections indicate that the greatest decrease in groundwater recharge and streamflow was projected under high emission scenarios in the 2080s. Under the medium and high emission scenarios, model results revealed that the frequency and severity of drought events would be the highest. The drought indices, the Reconnaissance Drought Index, RDI, Soil Moisture Deficit, SMD and Wetness Index, WI, predicted an increase in the severity of future drought events under the high emission scenarios. Increasing broadleaf forest area would decrease streamflow and groundwater recharge. Urban expansion could increase surface runoff. Decreasing winter barley and grass and increasing oil seed rape, would increase SMD and slightly decrease river flow. Findings of this study are helpful in the planning and management of the water resources considering the impact of climate and land use changes on variability in the availability of surface and groundwater resources.

scholarly journals Loss of connectivity among island-dwelling Peary caribou following sea ice decline

2016 ◽  
Vol 12 (9) ◽  
pp. 20160235 ◽  
Author(s):  
Deborah A. Jenkins ◽  
Nicolas Lecomte ◽  
James A. Schaefer ◽  
Steffen M. Olsen ◽  
Didier Swingedouw ◽  
...  
Keyword(s):  
Sea Ice ◽  
Population Connectivity ◽  
Future Climate Change ◽  
Landscape Resistance ◽  
Population Mixing ◽  
Sea Ice Decline ◽  
Rapid Changes ◽  
High Emission ◽  
High Emission Scenario

Global warming threatens to reduce population connectivity for terrestrial wildlife through significant and rapid changes to sea ice. Using genetic fingerprinting, we contrasted extant connectivity in island-dwelling Peary caribou in northern Canada with continental-migratory caribou. We next examined if sea-ice contractions in the last decades modulated population connectivity and explored the possible impact of future climate change on long-term connectivity among island caribou. We found a strong correlation between genetic and geodesic distances for both continental and Peary caribou, even after accounting for the possible effect of sea surface. Sea ice has thus been an effective corridor for Peary caribou, promoting inter-island connectivity and population mixing. Using a time series of remote sensing sea-ice data, we show that landscape resistance in the Canadian Arctic Archipelago has increased by approximately 15% since 1979 and may further increase by 20–77% by 2086 under a high-emission scenario (RCP8.5). Under the persistent increase in greenhouse gas concentrations, reduced connectivity may isolate island-dwelling caribou with potentially significant consequences for population viability.

scholarly journals A 40-million-year history of atmospheric CO 2

2013 ◽  
Vol 371 (2001) ◽  
pp. 20130096 ◽  
Author(s):  
Yi Ge Zhang ◽  
Mark Pagani ◽  
Zhonghui Liu ◽  
Steven M. Bohaty ◽  
Robert DeConto
Keyword(s):  
Middle Miocene ◽  
Carbon Fixation ◽  
Middle Eocene ◽  
Ice Sheet ◽  
Algal Growth ◽  
Equatorial Atlantic ◽  
Antarctic Ice Sheet ◽  
The Past ◽  
Wide Range

The alkenone– p CO 2 methodology has been used to reconstruct the partial pressure of ancient atmospheric carbon dioxide ( p CO 2 ) for the past 45 million years of Earth's history (Middle Eocene to Pleistocene epochs). The present long-term CO 2 record is a composite of data from multiple ocean localities that express a wide range of oceanographic and algal growth conditions that potentially bias CO 2 results. In this study, we present a p CO 2 record spanning the past 40 million years from a single marine locality, Ocean Drilling Program Site 925 located in the western equatorial Atlantic Ocean. The trends and absolute values of our new CO 2 record site are broadly consistent with previously published multi-site alkenone–CO 2 results. However, new p CO 2 estimates for the Middle Miocene are notably higher than published records, with average p CO 2 concentrations in the range of 400–500 ppm. Our results are generally consistent with recent p CO 2 estimates based on boron isotope-pH data and stomatal index records, and suggest that CO 2 levels were highest during a period of global warmth associated with the Middle Miocene Climatic Optimum (17–14 million years ago, Ma), followed by a decline in CO 2 during the Middle Miocene Climate Transition (approx. 14 Ma). Several relationships remain contrary to expectations. For example, benthic foraminiferal δ 18 O records suggest a period of deglaciation and/or high-latitude warming during the latest Oligocene (27–23 Ma) that, based on our results, occurred concurrently with a long-term decrease in CO 2 levels. Additionally, a large positive δ 18 O excursion near the Oligocene–Miocene boundary (the Mi-1 event, approx. 23 Ma), assumed to represent a period of glacial advance and retreat on Antarctica, is difficult to explain by our CO 2 record alone given what is known of Antarctic ice sheet history and the strong hysteresis of the East Antarctic Ice Sheet once it has grown to continental dimensions. We also demonstrate that in the Neogene with low CO 2 levels, algal carbon concentrating mechanisms and spontaneous biocarbonate–CO 2 conversions are likely to play a more important role in algal carbon fixation, which provides a potential bias to the alkenone– p CO 2 method.

scholarly journals Climate Change Impacts on Groundwater Recharge in Cold and Humid Climates: Controlling Processes and Thresholds

Climate ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 6
Author(s):  
Emmanuel Dubois ◽  
Marie Larocque ◽  
Sylvain Gagné ◽  
Marco Braun
Keyword(s):  
Climate Change ◽  
Groundwater Recharge ◽  
Water Resource Management ◽  
Global Climate Models ◽  
Future Climate Change ◽  
Temperature Changes ◽  
Wide Range ◽  
Long Term Changes ◽  
Precipitation And Temperature

Long-term changes in precipitation and temperature indirectly impact aquifers through groundwater recharge (GWR). Although estimates of future GWR are needed for water resource management, they are uncertain in cold and humid climates due to the wide range in possible future climatic conditions. This work aims to (1) simulate the impacts of climate change on regional GWR for a cold and humid climate and (2) identify precipitation and temperature changes leading to significant long-term changes in GWR. Spatially distributed GWR is simulated in a case study for the southern Province of Quebec (Canada, 36,000 km2) using a water budget model. Climate scenarios from global climate models indicate warming temperatures and wetter conditions (RCP4.5 and RCP8.5; 1951–2100). The results show that annual precipitation increases of >+150 mm/yr or winter precipitation increases of >+25 mm will lead to significantly higher GWR. GWR is expected to decrease if the precipitation changes are lower than these thresholds. Significant GWR changes are produced only when the temperature change exceeds +2 °C. Temperature changes of >+4.5 °C limit the GWR increase to +30 mm/yr. This work provides useful insights into the regional assessment of future GWR in cold and humid climates, thus helping in planning decisions as climate change unfolds. The results are expected to be comparable to those in other regions with similar climates in post-glacial geological environments and future climate change conditions.

scholarly journals Masers in evolved star winds

2012 ◽  
Vol 8 (S287) ◽  
pp. 199-208
Author(s):  
Anita M. S. Richards
Keyword(s):  
Evolutionary Stage ◽  
Interferometric Imaging ◽  
Physical Conditions ◽  
The Past ◽  
Evolved Stars ◽  
Multiple Observations ◽  
Wide Range ◽  
The Many ◽  
Term Monitoring

AbstractThis review summarises current observations of masers around evolved stars and models for their location and behaviour, followed by some of the many highlights from the past 5 years. Some of these have been the fruition of long-term monitoring, a vital aspect of study of stars which are both periodically variable and prone to rapid outbursts or transition to a new evolutionary stage. Interferometric imaging of masers provide the highest-resolution probes of the stellar wind, but their exponential amplification and variability means that multiple observations are needed to investigate questions such as what drives the wind from the stellar surface; why does it accelerate slowly over many tens of stellar radii; what causes maser variability. VLBI parallaxes have improved our understanding of individual objects and of Galactic populations. Masers from wide range of binary and post-AGB objects are accessible to sensitive modern instruments, including energetic symbiotic systems. Masers have been detected up to THz frequencies withHerscheland ALMA's ability to resolve a wide range of maser and thermal lines will provide accurate constraints on physical conditions including during dust formation.

Toward a Medical Understanding of Marihuana

1969 ◽  
Vol 14 (6) ◽  
pp. 591-600 ◽  
Author(s):  
Conrad J. Schwarz
Keyword(s):  
English Language ◽  
Medical Literature ◽  
Experimental Studies ◽  
Personal Characteristics ◽  
Short Term ◽  
The Past ◽  
Wide Range ◽  
Indian Hemp ◽  
Made In

This paper is based on a review of the English language medical literature over the past 35 years on Indian Hemp, with direct reference being made to the more significant articles published during that time. The paucity of direct experimental observation is noted and the difficulties in experimental studies are highlighted by descriptions of the wide variations in the potency of Indian Hemp derivatives. Specific references are provided for the wide range of observations made in relation to acute and chronic physical and psychological effects, personal characteristics of the users and possible factors in causation. It is concluded that marihuana is a poorly defined intoxicant which varies in potency, deteriorates with time and whose chemical composition is largely unknown at present. There are wide variations in human response and the state of intoxication itself carries with it varying degrees of unpleasant physical and psychological experiences. The association between hashish and, to a lesser extent, marihuana and short-term and long-term complications is discussed in relation to complex variables, of which the drug is but one factor.

Field Studies: Bringing Historical Records Down to Earth

2019 ◽  
pp. 34-47
Author(s):  
Emily W. B. Russell Southgate
Keyword(s):  
Aerial Photography ◽  
Field Studies ◽  
Soil Characteristics ◽  
Historical Records ◽  
Remote Imaging ◽  
The Past ◽  
Ground Survey ◽  
Wide Range ◽  
Over Time

There are many field techniques that take research beyond what can be found in written documents. Clues to the past are hidden in such subtle (and not so subtle) features as topographic modifications, soils, and tree trunks. Field studies search for evidence of conditions and for their resultant effects through a variety of techniques. Features may be evident from a ground survey, located precisely through GPS. Remote imaging, using a variety of techniques from simple aerial photography to lidar, reveal hidden patterns, that may then be studied on the ground. Archeological study relates the patterns found on the ground to human activities, as they have changed over time. Dendroecology interprets records left in tree rings. Some studies look at stands of different ages to study change over time, and long-term studies trace change in individual stands. In these field studies that look at the past, soil characteristics and materials hidden in the soil, such as DNA, stable isotopes and charcoal, can reveal details of past processes and species. These methods are illustrated with examples from a wide range of biomes.

scholarly journals Limits of long-term selection against Neandertal introgression

2019 ◽  
Vol 116 (5) ◽  
pp. 1639-1644 ◽  
Author(s):  
Martin Petr ◽  
Svante Pääbo ◽  
Janet Kelso ◽  
Benjamin Vernot
Keyword(s):  
Negative Selection ◽  
Modern Human ◽  
Model Parameters ◽  
Human Populations ◽  
Modern Humans ◽  
High Coverage ◽  
Protein Coding ◽  
The Past ◽  
Wide Range

Several studies have suggested that introgressed Neandertal DNA was subjected to negative selection in modern humans. A striking observation in support of this is an apparent monotonic decline in Neandertal ancestry observed in modern humans in Europe over the past 45,000 years. Here, we show that this decline is an artifact likely caused by gene flow between modern human populations, which is not taken into account by statistics previously used to estimate Neandertal ancestry. When we apply a statistic that avoids assumptions about modern human demography by taking advantage of two high-coverage Neandertal genomes, we find no evidence for a change in Neandertal ancestry in Europe over the past 45,000 years. We use whole-genome simulations of selection and introgression to investigate a wide range of model parameters and find that negative selection is not expected to cause a significant long-term decline in genome-wide Neandertal ancestry. Nevertheless, these models recapitulate previously observed signals of selection against Neandertal alleles, in particular the depletion of Neandertal ancestry in conserved genomic regions. Surprisingly, we find that this depletion is strongest in regulatory and conserved noncoding regions and in the most conserved portion of protein-coding sequences.

Sign in / Sign up

Export Citation Format

Share Document