Understanding and predicting the effects of land‐use change to short rotation forestry (SRF) on soil carbon (C) is an important requirement for fully assessing the C mitigation potential of SRF as a ...bioenergy crop. There is little current knowledge of SRF in the UK and in particular a lack of consistent measured data sets on the direct impacts of land use change on soil C stocks. The ECOSSE model was developed to simulate soil C dynamics and greenhouse gas (GHG) emissions in mineral and organic soils. The ECOSSE model has already been applied spatially to simulate land‐use change impacts on soil C and GHG emissions. However, it has not been extensively evaluated under SRF. Eleven sites comprising 29 transitions in Britain, representing land‐use change from nonwoodland land uses to SRF, were selected to evaluate the performance of ECOSSE in predicting soil C and soil C change in SRF plantations. The modelled C under SRF showed a strong correlation with the soil C measurements at both 0–30 cm (R = 0.93) and 0–100 cm soil depth (R = 0.82). As for the SRF plots, the soil C at the reference sites have been accurately simulated by the model. The extremely high correlation for the reference fields (R ≥ 0.99) shows a good performance of the model spin‐up. The statistical analysis of the model performance to simulate soil C and soil C changes after land‐use change to SRF highlighted the absence of significant error between modelled and measured values as well as the absence of significant bias in the model. Overall, this evaluation reinforces previous studies on the ability of ECOSSE to simulate soil C and emphasize its accuracy to simulate soil C under SRF plantations.
Systems approaches have great potential for application in predictive ecology. In this paper, we present a range of examples, where systems approaches are being developed and applied at a range of ...scales in the field of global change and biogeochemical cycling. Systems approaches range from Bayesian calibration techniques at plot scale, through data assimilation methods at regional to continental scales, to multi-disciplinary numerical model applications at country to global scales. We provide examples from a range of studies and show how these approaches are being used to address current topics in global change and biogeochemical research, such as the interaction between carbon and nitrogen cycles, terrestrial carbon feedbacks to climate change and the attribution of observed global changes to various drivers of change. We examine how transferable the methods and techniques might be to other areas of ecosystem science and ecology.
1 Department of Medicine, Washington University
School of Medicine, St. Louis 63110; and 2 Departments
of Physiology and Internal Medicine and Diabetes and
Cardiovascular Biology Program, School of ...Medicine, University of
Missouri, Columbia, Missouri 65212
Muscle contractions cause
numerous disturbances in intracellular homeostasis. This makes
it impossible to use contracting muscle to identify which of the many
signals generated by contractions are responsible for stimulating
mitochondrial biogenesis. One purpose of this study was to evaluate the
usefulness of L6 myotubes, which do not contract, for studying
mitochondrial biogenesis. A second purpose was to evaluate further the
possibility that increases in cytosolic Ca 2+ can stimulate
mitochondrial biogenesis. Continuous exposure to 1 µM ionomycin, a
Ca 2+ ionophore, for 5 days induced an increase in
mitochondrial enzymes but also caused a loss of myotubes, as reflected
in an ~40% decrease in protein per dish. However, intermittent (5 h/day) exposure to ionomycin, or to caffeine or W7, which release
Ca 2+ from the sarcoplasmic reticulum, did not cause a
decrease in protein per dish. Raising cytosolic Ca 2+
intermittently with these agents induced significant increases in
mitochondrial enzymes. EGTA blocked most of this effect of ionomycin,
whereas dantrolene, which blocks Ca 2+ release from the
sarcoplasmic reticulum, largely prevented the increases in
mitochondrial enzymes induced by W7 and caffeine. These findings
provide evidence that intermittently raising cytosolic Ca 2+
stimulates mitochondrial biogenesis in muscle cells.
caffeine; exercise; gene expression; ionomycin; L6 myotubes
Landscape heterogeneity can be instrumental in determining local disease risk, pathogen persistence and spread. This is because different landscape features such as habitat type determine the ...abundance and spatial distributions of hosts and pathogen vectors. Therefore, disease prevalence and distribution are intrinsically linked to the hosts and vectors that utilise the different habitats. Here, we develop a simplified reaction diffusion model of the louping-ill virus and red grouse (
Lagopus lagopus scoticus
) system to investigate the occurrence of a tick-borne pathogen and the effect of host movement and landscape structure. Ticks (
Ixodes ricinus
), the virus-vector, are dispersed by a virally incompetent tick host, red deer (
Cervus elephus
), between different habitats, whilst the virus infects only red grouse. We investigated how deer movement between different habitats (forest and moorland) affected tick distribution and hence prevalence of infected ticks and grouse and hence, the effect of habitat size ratio and fragmentation on infection. When habitat type has a role in the survival of the pathogen vector, we demonstrated that habitat fragmentation can have a considerable effect on infection. These results highlight the importance of landscape heterogeneity and the proximity and size of adjacent habitats when predicting disease risk in a particular location. In addition, this model could be useful for other pathogen systems with generalist vectors and may inform policy on possible disease management strategies that incorporate host movements.
Abstract
In this paper, we focus on the impact on soil organic carbon (
SOC
) of two dedicated energy crops: perennial grass
M
iscanthus x
G
iganteus
(
M
iscanthus
) and short rotation coppice (
SRC
...)‐willow. The amount of
SOC
sequestered in the soil is a function of site‐specific factors including soil texture, management practices, initial
SOC
levels and climate; for these reasons, both losses and gains in
SOC
were observed in previous
M
iscanthus
and
SRC
‐willow studies. The
ECOSSE
model was developed to simulate soil C dynamics and greenhouse gas emissions in mineral and organic soils. The performance of
ECOSSE
has already been tested at site level to simulate the impacts of land‐use change to short rotation forestry (
SRF
) on
SOC
. However, it has not been extensively evaluated under other bioenergy plantations, such as
M
iscanthus
and
SRC
‐willow. Twenty‐nine locations in the
U
nited
K
ingdom, comprising 19 paired transitions to
SRC
‐willow and 20 paired transitions to
M
iscanthus
, were selected to evaluate the performance of
ECOSSE
in predicting
SOC
and
SOC
change from conventional systems (arable and grassland) to these selected bioenergy crops. The results of the present work revealed a strong correlation between modelled and measured
SOC
and
SOC
change after transition to
M
iscanthus
and
SRC
‐willow plantations, at two soil depths (0–30 and 0–100 cm), as well as the absence of significant bias in the model. Moreover, model error was within (i.e. not significantly larger than) the measurement error. The high degrees of association and coincidence with measured
SOC
under
M
iscanthus
and
SRC
‐willow plantations in the
U
nited
K
ingdom, provide confidence in using this process‐based model for quantitatively predicting the impacts of future land use on
SOC
, at site level as well as at national level.
An autochthonous model of pancreatic ductal adenocarcinoma (PDA) permitted the analysis of why immunotherapy is ineffective in this human disease. Despite finding that PDA-bearing mice had cancer ...cell-specific CD8 ⁺ T cells, the mice, like human patients with PDA, did not respond to two immunological checkpoint antagonists that promote the function of T cells: anti-cytotoxic T-lymphocyte-associated protein 4 (α-CTLA-4) and α-programmed cell death 1 ligand 1 (α-PD-L1). Immune control of PDA growth was achieved, however, by depleting carcinoma-associated fibroblasts (CAFs) that express fibroblast activation protein (FAP). The depletion of the FAP ⁺ stromal cell also uncovered the antitumor effects of α-CTLA-4 and α-PD-L1, indicating that its immune suppressive activity accounts for the failure of these T-cell checkpoint antagonists. Three findings suggested that chemokine (C-X-C motif) ligand 12 (CXCL12) explained the overriding immunosuppression by the FAP ⁺ cell: T cells were absent from regions of the tumor containing cancer cells, cancer cells were coated with the chemokine, CXCL12, and the FAP ⁺ CAF was the principal source of CXCL12 in the tumor. Administering AMD3100, a CXCL12 receptor chemokine (C-X-C motif) receptor 4 inhibitor, induced rapid T-cell accumulation among cancer cells and acted synergistically with α-PD-L1 to greatly diminish cancer cells, which were identified by their loss of heterozygosity of Trp53 gene. The residual tumor was composed only of premalignant epithelial cells and inflammatory cells. Thus, a single protein, CXCL12, from a single stromal cell type, the FAP ⁺ CAF, may direct tumor immune evasion in a model of human PDA.
The adverse effects of prenatal alcohol exposure constitute a continuum of disabilities (fetal alcohol spectrum disorders FASD). In 1996, the Institute of Medicine established diagnostic categories ...delineating the spectrum but not specifying clinical criteria by which diagnoses could be assigned. In 2005, the authors published practical guidelines operationalizing the Institute of Medicine categories, allowing for standardization of FASD diagnoses in clinical settings. The purpose of the current report is to present updated diagnostic guidelines based on a thorough review of the literature and the authors' combined expertise based on the evaluation of >10 000 children for potential FASD in clinical settings and in epidemiologic studies in conjunction with National Institute on Alcohol Abuse and Alcoholism-funded studies, the Collaborative Initiative on Fetal Alcohol Spectrum Disorders, and the Collaboration on FASD Prevalence. The guidelines were formulated through conference calls and meetings held at National Institute on Alcohol Abuse and Alcoholism offices in Rockville, MD. Specific areas addressed include the following: precise definition of documented prenatal alcohol exposure; neurobehavioral criteria for diagnosis of fetal alcohol syndrome, partial fetal alcohol syndrome, and alcohol-related neurodevelopmental disorder; revised diagnostic criteria for alcohol-related birth defects; an updated comprehensive research dysmorphology scoring system; and a new lip/philtrum guide for the white population, incorporating a 45-degree view. The guidelines reflect consensus among a large and experienced cadre of FASD investigators in the fields of dysmorphology, epidemiology, neurology, psychology, developmental/behavioral pediatrics, and educational diagnostics. Their improved clarity and specificity will guide clinicians in accurate diagnosis of infants and children prenatally exposed to alcohol.
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