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1.
Int J Biometeorol ; 62(5): 823-832, 2018 May.
Article in English | MEDLINE | ID: mdl-29196806

ABSTRACT

Crop growth models have many uncertainties that affect the yield response to climate change. Based on that, the aim of this study was to evaluate the sensitivity of crop models to systematic changes in climate for simulating soybean attainable yield in Southern Brazil. Four crop models were used to simulate yields: AQUACROP, MONICA, DSSAT, and APSIM, as well as their ensemble. The simulations were performed considering changes of air temperature (0, + 1.5, + 3.0, + 4.5, and + 6.0 °C), [CO2] (380, 480, 580, 680, and 780 ppm), rainfall (- 30, - 15, 0, + 15, and + 30%), and solar radiation (- 15, 0, + 15), applied to daily values. The baseline climate was from 1961 to 2014, totalizing 53 crop seasons. The crop models simulated a reduction of attainable yield with temperature increase, reaching 2000 kg ha-1 for the ensemble at + 6 °C, mainly due to shorter crop cycle. For rainfall, the yield had a higher rate of reduction when it was diminished than when rainfall was increased. The crop models increased yield variability when solar radiation was changed from - 15 to + 15%, whereas [CO2] rise resulted in yield gains, following an asymptotic response, with a mean increase of 31% from 380 to 680 ppm. The models used require further attention to improvements in optimal and maximum cardinal temperature for development rate; runoff, water infiltration, deep drainage, and dynamic of root growth; photosynthesis parameters related to soil water availability; and energy balance of soil-plant system to define leaf temperature under elevated CO2.


Subject(s)
Climate Change , Crops, Agricultural/growth & development , Glycine max/growth & development , Models, Theoretical , Brazil , Carbon Dioxide/analysis , Computer Simulation , Crops, Agricultural/metabolism , Plant Transpiration , Rain , Glycine max/metabolism , Sunlight , Temperature
2.
Transl Psychiatry ; 3: e248, 2013 Apr 23.
Article in English | MEDLINE | ID: mdl-23612047

ABSTRACT

Microstructural white matter changes have been reported in the brains of patients across a range of psychiatric disorders. Evidence now demonstrates significant overlap in these regions in patients with affective and psychotic disorders, thus raising the possibility that these conditions share common neurobiological processes. If affective and psychotic disorders share these disruptions, it is unclear whether they occur early in the course or develop gradually with persistence or recurrence of illness. Utilisation of a clinical staging model, as an adjunct to traditional diagnostic practice, is a viable mechanism for measuring illness progression. It is particularly relevant in young people presenting early in their illness course. It also provides a suitable framework for determining the timing of emergent brain alterations, including disruptions of white matter tracts. Using diffusion tensor imaging, we investigated the integrity of white matter tracts in 74 patients with sub-syndromal psychiatric symptoms as well as in 69 patients diagnosed with established psychosis or affective disorder and contrasted these findings with those of 39 healthy controls. A significant disruption in white matter integrity was found in the left anterior corona radiata and in particular the anterior thalamic radiation for both the patients groups when separately contrasted with healthy controls. Our results suggest that patients with sub-syndromal symptoms exhibit discernable early white matter changes when compared with healthy control subjects and more significant disruptions are associated with clinical evidence of illness progression.


Subject(s)
Brain/ultrastructure , Mood Disorders/pathology , Psychotic Disorders/pathology , Adolescent , Adult , Brain/pathology , Case-Control Studies , Diffusion Tensor Imaging , Disease Progression , Female , Humans , Longitudinal Studies , Magnetic Resonance Imaging , Male , Neuroimaging , Prodromal Symptoms , Psychiatric Status Rating Scales , Young Adult
3.
Neurosurg Rev ; 36(2): 205-14; discussion 214, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23187966

ABSTRACT

Historically, brain tumour resection has relied upon standardised anatomical atlases and classical mapping techniques for successful resection. While these have provided adequate results in the past, the emergence of new technologies has heralded a wave of less invasive, patient-specific techniques for the mapping of brain function. Functional magnetic resonance imaging (fMRI) and, more recently, diffusion tensor imaging (DTI) are two such techniques. While fMRI is able to highlight localisation of function within the cortex, DTI represents the only technique able to elucidate white matter structures in vivo. Used in conjunction, both of these techniques provide important presurgical information for thorough preoperative planning, as well as intraoperatively via integration into frameless stereotactic neuronavigational systems. Together, these techniques show great promise for improved neurosurgical outcomes. While further research is required for more widespread clinical validity and acceptance, results from the literature provide a clear road map for future research and development to cement these techniques into the clinical setup of neurosurgical departments globally.


Subject(s)
Brain Neoplasms/diagnosis , Diffusion Tensor Imaging/methods , Magnetic Resonance Imaging/methods , Preoperative Care/methods , Brain/pathology , Brain/surgery , Brain Neoplasms/surgery , Humans , Image Processing, Computer-Assisted , Neuronavigation/methods , Oxygen/blood , Patient Care Planning
4.
Am J Physiol Endocrinol Metab ; 299(2): E249-57, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20484013

ABSTRACT

The excess accumulation of lipids in islets is thought to contribute to the development of diabetes in obesity by impairing beta-cell function. However, lipids also serve a nutrient function in islets, and fatty acids acutely increase insulin secretion. A better understanding of lipid metabolism in islets will shed light on complex effects of lipids on beta-cells. Adipose differentiation-related protein (ADFP) is localized on the surface of lipid droplets in a wide range of cells and plays an important role in intracellular lipid metabolism. We found that ADFP was highly expressed in murine beta-cells. Moreover, islet ADFP was increased in mice on a high-fat diet (3.5-fold of control) and after fasting (2.5-fold of control), revealing dynamic changes in ADFP in response to metabolic cues. ADFP expression was also increased by addition of fatty acids in human islets. The downregulation of ADFP in MIN6 cells by antisense oligonucleotide (ASO) suppressed the accumulation of triglycerides upon fatty acid loading (56% of control) along with a reduction in the mRNA levels of lipogenic genes such as diacylglycerol O-acyltransferase-2 and fatty acid synthase. Fatty acid uptake, oxidation, and lipolysis were also reduced by downregulation of ADFP. Moreover, the reduction of ADFP impaired the ability of palmitate to increase insulin secretion. These findings demonstrate that ADFP is important in regulation of lipid metabolism and insulin secretion in beta-cells.


Subject(s)
Insulin/biosynthesis , Islets of Langerhans/physiology , Lipid Metabolism/physiology , Membrane Proteins/physiology , Animals , Blood Glucose/metabolism , Blotting, Western , Cells, Cultured , Down-Regulation/physiology , Fluorescent Antibody Technique , Humans , Immunohistochemistry , Insulin/metabolism , Insulin Secretion , Islets of Langerhans/cytology , Islets of Langerhans/metabolism , Lipolysis/physiology , Male , Mice , Mice, Inbred C57BL , Nutritional Physiological Phenomena , Perilipin-2 , RNA/biosynthesis , RNA/isolation & purification , Triglycerides/metabolism
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