Predictability of the quasi-biennial oscillation and its northern winter teleconnection on seasonal to decadal timescales

Journal ArticlePublished version used with permision of the publisher.The predictability of the quasi-biennial oscillation (QBO) is examined in initialized climate forecasts extending out to lead times of years. We use initialized retrospective predictions made with coupled ocean-atmosphere climate models that have an internally generated QBO. We demonstrate predictability of the QBO extending more than 3 years into the future, well beyond timescales normally associated with internal atmospheric processes. Correlation scores with observational analyses exceed 0.7 at a lead time of 12 months. We also examine the variation of predictability with season and QBO phase and find that skill is lowest in winter. An assessment of perfect predictability suggests that higher skill may be achievable through improved initialization and climate modeling of the QBO, although this may depend on the realism of gravity wave source parameterizations in the models. Finally, we show that skilful prediction of the QBO itself does not guarantee predictability of the extratropical winter teleconnection that is important for surface winter climate prediction. Key Points The QBO is skilfully predicted in seasonal-decadal forecast systems Further improvements in predictions of the QBO are possible The QBO winter surface teleconnection is reproduced with mixed succes

Modifiable risk factors associated with bone deficits in childhood cancer survivors

<p>Abstract</p> <p>Background</p> <p>To determine the prevalence and severity of bone deficits in a cohort of childhood cancer survivors (CCS) compared to a healthy sibling control group, and the modifiable factors associated with bone deficits in CCS.</p> <p>Methods</p> <p>Cross-sectional study of bone health in 319 CCS and 208 healthy sibling controls. Bone mineral density (BMD) was measured by dual-energy x-ray absorptiometry (DXA). Generalized estimating equations were used to compare measures between CCS and controls. Among CCS, multivariable logistic regression was used to evaluate odds ratios for BMD Z-score ≤ -1.</p> <p>Results</p> <p>All subjects were younger than 18 years of age. Average time since treatment was 10.1 years (range 4.3 - 17.8 years). CCS were 3.3 times more likely to have whole body BMD Z-score ≤ -1 than controls (95% CI: 1.4-7.8; p = 0.007) and 1.7 times more likely to have lumbar spine BMD Z-score ≤ -1 than controls (95% CI: 1.0-2.7; p = 0.03). Among CCS, hypogonadism, lower lean body mass, higher daily television/computer screen time, lower physical activity, and higher inflammatory marker IL-6, increased the odds of having a BMD Z-score ≤ -1.</p> <p>Conclusions</p> <p>CCS, less than 18 years of age, have bone deficits compared to a healthy control group. Sedentary lifestyle and inflammation may play a role in bone deficits in CCS. Counseling CCS and their caretakers on decreasing television/computer screen time and increasing activity may improve bone health.</p

Top-down estimates of European CH₄ and N₂O emissions based on four different inverse models

European CH4 and N2O emissions are estimated for 2006 and 2007 using four inverse modelling systems, based on different global and regional Eulerian and Lagrangian transport models. This ensemble approach is designed to provide more realistic estimates of the overall uncertainties in the derived emissions, which is particularly important for verifying bottom-up emission inventories. We use continuous observations from 10 European stations (including 5 tall towers) for CH4 and 9 continuous stations for N2O, complemented by additional European and global discrete air sampling sites. The available observations mainly constrain CH4 and N2O emissions from northwestern and eastern Europe. The inversions are strongly driven by the observations and the derived total emissions of larger countries show little dependence on the emission inventories used a priori. Three inverse models yield 26–56% higher total CH4 emissions from north-western and eastern Europe compared to bottom-up emissions reported to the UNFCCC, while one model is close to the UNFCCC values. In contrast, the inverse modelling estimates of European N2O emissions are in general close to the UNFCCC values, with the overall range from all models being much smaller than the UNFCCC uncertainty range for most countries. Our analysis suggests that the reported uncertainties for CH4 emissions might be underestimated, while those for N2O emissions are likely overestimated.JRC.H.2-Air and Climat

The Bolund Experiment, Part I: Flow Over a Steep, Three-Dimensional Hill

We present an analysis of data from a measurement campaign performed at the Bolund peninsula in Denmark in the winter of 2007–2008. Bolund is a small isolated hill exhibiting a significantly steep escarpment in the main wind direction. The physical shape of Bolund represents, in a scaled-down form, a typical wind turbine site in complex terrain. Because of its small size the effect of atmospheric stratification can be neglected, which makes the Bolund experiment ideal for the validation of neutral flow models and hence model scenarios most relevant to wind energy. We have carefully investigated the upstream conditions. With a 7-km fetch over water, the incoming flow is characterized as flow over flat terrain with a local roughness height based on the surface momentum flux. The nearly perfect upstream conditions are important in forming a meaningful quantitative description of the flow over the Bolund hill. Depending on the wind direction, we find a maximum speed-up of 30% at the hill top accompanied by a maximum 300% enhancement of turbulence intensity. A closer inspection reveals transient behaviour with recirculation zones. From the wind energy context, this implies that the best site for erecting a turbine based on resource constraints unfortunately also imposes a penalty of high dynamic loads. On the lee side of Bolund, recirculation occurs with the turbulence intensity remaining significantly enhanced even at one hill length downstream. Its transient behaviour and many recirculation zones place Bolund in a category in which the linear flow theory is not applicable

The significance of survivin and nectin-4 expression in the prognosis of breast carcinoma

To investigate the prognostic significance of Survivin and Nectin-4 expression in breast carcinomas. Imprint smears were obtained from 140 breast carcinoma specimens and studied immunocytochemically for the expression of Survivin and Nectin-4. The results were correlated with several clinicopathological parameters, including five-year survival. Increased Survivin staining pattern correlated with increased grade (p&lt; 0.0001), increased lymph node invasion (p&lt; 0.0001), increased tumor size and reduced survival (p&lt; 0.0001). Elevated Nectin-4 expression also correlated significantly with increased grade (p&lt; 0.0001), increased tumor size (p&lt; 0.0001) and reduced survival (p&lt; 0.0001). In addition, Survivin and Nectin-4 staining patterns correlated strongly with one another (p&lt; 0.0001). However, on multivariate analysis, neither Survivin nor Nectin-4 expression seemed to have an independent impact on survival in our study cases. The findings of our study suggest that increased expression of Survivin and Nectin-4 may indicate a worse prognosis in breast cancer patients. The exact implications of the expression of these markers in breast cancer prognosis and treatment remain to be clarified. © Polish Society for Histochemistry and Cytochemistry

Apoptosis-related factors p53, bcl-2 and the defects of force transmission in dilated cardiomyopathy

The etiology of heart failure in dilated cardiomyopathy involves multiple agents. The purpose of this study was to investigate the presence of apoptosis-related proteins p53, bcl-2, and the defects of force transmission in end-stage dilated cardiomyopathy.We studied myocardial samples from 20 hearts with histologic findings of dilated cardiomyopathy. Myocardial samples obtained from 10 normal hearts were used as controls. An immunohistochemical method was performed with the use of desmin, N-cadherin, p53, and bcl-2 antibodies.The expression of desmin and N-cadherin was much more pronounced in dilated cardiomyopathy, and both of them were arranged disorderly. On the other hand, increased expression of p53 is associated with progressive loss of myocytes by apoptosis in heart failure, and increased expression of bcl-2 represents a possible compensatory antiapoptotic mechanism.The increased amount and the irregular distribution of desmin and N-cadherin in dilated cardiomyopathy may compensate for the loss of cellular stability due to the loss of contractile material. These alterations contribute to the deterioration of contractile function in heart failure. Furthermore, the prevalence of an apoptotic or compensatory antiapoptotic mechanism may influence the evolution of heart failure in dilated cardiomyopathy. © 2010 Elsevier GmbH

CD24 expression has a prognostic impact in breast carcinoma

We investigated the prognostic significance of BAG-1 and CD24 in invasive breast carcinomas. Seventy cases of invasive breast carcinoma were studied immunocytochemically for the expression of BAG-1 and CD24. The results were correlated with several prognostic parameters, including 5-year survival. Univariate analysis showed a significant correlation of BAG-1 and CD24 overall positive staining with several adverse prognostic parameters, such as increased stage (p&lt;0.0001), tumor grade 3 (p=0.016 and p=0.02, respectively), positive lymph nodes (p&lt;0.0001), and increased tumor size (p&lt;0.0001). Similar results were found for BAG-1 nuclear staining, as well as for positive cytoplasmic CD24 expression. Both of our markers studied had a significant, negative effect on survival. Multivariate analysis further revealed an independent prognostic impact for CD24 overall staining. The results of our study showed that overall cytoplasmic and especially nuclear BAG-1 expression, as well as overall and cytoplasmic CD24 expression, correlates with adverse prognostic parameters. An independent prognostic value for overall CD24 staining was also demonstrated. © 2009 Elsevier GmbH. All rights reserved

From cell to heart: The impact of the cell organelles dysfunction on heart disease

Cellular morphology reflects biologic behavior and activity of the tissue and of the organ also reflects the genetic and molecular biology of the cells themselves. This intermediary position places examination of the cell in a key role to our understanding of the innumerable processes that affect this closely knit chain, from molecules to host. A large volume of the cell is occupied by organelles that come in a variety of shapes and sizes. Organelles are dynamic to maintain homeostasis and adjust to the various functions of the cell. The cardiovascular system is metabolically very active and is therefore particularly vulnerable to defects of the cellular substructures, such as the mitochondrial respiratory chain. Given the functional complexity of the cardiovascular system, it is not surprising that defects in cell organelles produce diverse clinical manifestations. Organelle dysfunction is being recognized as the basis of a wide variety of heart diseases. In this review, the authors discuss the relationship between organelle structure and function in myocardial cells and how these organelles have been linked to the cardiovascular diseases. © 2018 Italian Federation of Cardiology. All rights reserved