bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic crop sequencing in Western Australian cropping systems
Authors: Malik Raj S. , Seymour Mark , French Robert J. , Kirkegaard John A. , Lawes Roger A. , Liebig Mark A.
Published: May 2015

During the last two decades in Western Australia, the traditional mixed farming system has been increasingly displaced by intensive crop sequences dominated by wheat. Intensive wheat sequences are usually maintained by using suitable breaks, including pasture, fallow, or alternative cereal, oilseed and legume crops, to control weeds and disease, or maintain the supply of nitrogen to crops. New cereal fungicide options may also assist to maintain intensive cereal systems by suppressing soilborne cereal diseases. To guide the successful diversification of intensive cereal systems, we evaluated the effect of a 2-year experimental matrix of 10 different sequence options. Wheat in the sequence was treated with the fluquinconazole fungicide Jockey (wheat + J) to control soilborne pathogens, or with the usual seed dressing of flutriafol fungicide (wheat – J), used for control of bunts and smuts only. The sequences were wheat + J, wheat – J, barley, grain oats, oaten hay, canola, lupin, field pea, oat–vetch green manure, bare fallow) in which all treatment combinations were grown in year 2 following the same 10 treatments in year 1. In year 3, wheat + J was grown across the entire area as the test crop. In year 2, grain yields of all crops were reduced when crops were grown on their own residues, including wheat (22% reduction), canola (46%), lupin (40%) and field pea (51%). Wheat + J significantly outyielded wheat – J by 300 kg ha–1 in year 1 (14% increase) and 535 kg ha–1 in year 2 (26% increase). Wheat + J was more responsive to break crops than wheat – J in both year 1 and year 2. Break crops sown in year 1, such as canola, fallow, field pea, lupin and oaten hay, continued to have a positive effect on year 3 wheat + J yields. This study has highlighted the importance of break crops to following cereal crops, and provided an example in which a seed-dressing fungicide fluquinconazole in the presence of low levels of disease consistently improved wheat yields.
Considering long-term ecological effects on future land-use options when making tactical break-crop decisions in cropping systems
Authors: Renton Michael , Lawes Roger , Metcalf Tess , Robertson Michael
Published: May 2015

In cropping systems where one type of crop dominates for economic reasons, farmers may employ alternative cropping or pasture options for strategic purposes such as controlling weed populations, reducing crop disease, and accumulating soil nitrogen. Tactical decisions regarding break crops often involve understanding the economic implications of several interacting bio-physical factors, along with complex trade-offs between short-term benefits, such as immediate profit, and long-term ecological problems, such as increased weed seedbank. Modelling analysis regarding tactical crop-sequencing and break-crop decisions has generally not addressed these longer term dynamic factors. In this study we adapted an analysis and modelling framework (LUSO), originally designed to aid understanding of the long-term strategic planning of agricultural crop and pasture rotations, so that it can be used to analyse immediate tactical decisions regarding break crops and sequencing, while still accounting for both short- and long-term implications of these decisions. We show how the revised framework was applied to two example scenarios and demonstrate that in both cases it can be used for simple decision-support, as well as more in-depth analysis and insight into the factors influencing the immediate decision.
Gaining insight into the risks, returns and value of perfect knowledge for crop sequences by comparing optimal sequences with those proposed by agronomists
Authors: Lawes Roger , Renton Michael
Published: May 2015

Crop rotation, in which a legume, pasture, fallow or oilseed ‘break crop’ is grown after a cereal crop to manage soil-borne disease and weeds and, on occasions, to fix nitrogen, is one of the oldest techniques in agriculture. Valuing of crop rotations is complicated because the profitability of particular crop species changes with the prevalence of biotic stresses and varies with seasonal factors such as rainfall. With the Land Use Sequence Optimiser (LUSO) and the Agricultural Production Systems Simulator (APSIM) crop model, we generate an optimum land-use strategy for various biotic stresses and land-use options for a semi-arid grain-growing region in Australia. Over a 10-year time horizon, we compare the performance and variability of an optimal sequence with three sequences recommended by local agronomists. The agronomists recommended strategic sequences to manage weeds and disease and to maximise profit. The optimal crop sequence, with perfect knowledge, selected a mixture of grain legume, oilseed, cereal crops and pastures to manage biotic stresses and generate profit. This sequence precisely timed a period of exploitation, when high-profit crops were repeatedly grown and the biotic stresses increase, with a period of rehabilitation, when low-profit break crops are grown to reduce the biotic stresses. The agronomists’ strategic sequences were either slightly more exploitative, grew more crops and allowed the biotic stresses to increase, or were more conservative and grew fewer profitable crops while managing the biotic stresses. Both strategic approaches were less profitable than the optimal crop sequence. The value of knowledge about a particular stress increases as its rate of accumulation in the farming system increases. With high levels of biotic weed stress, perfect knowledge was worth an additional AU$73 ha–1 year–1. In scenarios with lower levels of biotic weed stress, perfect knowledge was worth just $24 ha–1 year–1. Several measures of risk were defined, but there was no trade-off between profit and risk. Variability at the crop or enterprise scale did not necessarily translate into variability in profit when viewed over 10 years. Tools such as LUSO can help to determine the optimal crop sequence for a given series of enterprise options and a given level of biotic stress and explore the variability and risk associated with different enterprise choices.
Crop-sequence effects on productivity in a wheat-based cropping system at Wongan Hills, Western Australia
Authors: French R. J. , Malik R. S. , Seymour M.
Published: May 2015

Western Australian grain production is dominated by wheat, but growing wheat continually in unbroken sequences leads to increasing problems with soil nutrient depletion, root and leaf disease build-up, high weed burdens, and possibly other less well-defined production constraints. These can adversely affect both production and grain quality. Including breaks in the crop sequence in the form of break crops, pasture, or fallow can reduce these problems, but these breaks can be expensive to implement, in terms of both direct cost and forgone revenue. It is therefore critical to predict the response of subsequent wheat crops to a break in order to choose crop sequences rationally.
We conducted a 4-year experiment at Wongan Hills, Western Australia, evaluating how wheat productivity in a wheat-based cropping sequence is affected by including wheat, barley, lupins, triazine-tolerant and Roundup Ready® canola, oaten hay, volunteer pasture, serradella pasture, and chemical fallow. Wheat yield responded positively to fallow, lupins, oaten hay, volunteer pastures and serradella but not to barley or canola when compared with continuous wheat. Responses depended on seasonal conditions; in a dry year, a very large response occurred after fallow but not after lupin or serradella, whereas in a wetter year, there were large responses after these crops. Fallowing, cutting hay, crop-topping lupins, and spray-topping volunteer and serradella pasture all reduced seedset of annual ryegrass dramatically, and reduced weed competition was a major contributor to the observed break crop responses. Nitrogen fixation by lupins and serradella and water storage by fallow in a dry year were also important, but soilborne diseases did not contribute to wheat yield responses. Some yield responses persisted for at least 3 years, and the contribution of effects of weed competition to yield responses increased over this time. These results emphasise the importance of understanding which productivity constraints are present in a cropping system at a given time when deciding whether a break is necessary and which is the most appropriate break. The results also emphasise the importance of managing the wheat crop after a break to maximise the response and its longevity.
Porcupine inhibitor suppresses paracrine Wnt-driven growth of
Rnf43;Znrf3
-mutant neoplasia
Authors: Koo Bon-Kyoung , van Es Johan H. , van den Born Maaike , Clevers Hans
Published: May 2015

Significance

Rnf43 (RING finger protein 43) and Znrf3 (zinc/RING finger protein 3), encoded by stem cell-specific Wnt (wingless-int) target genes, constitute a crucial negative feedback loop in the Wnt signaling pathway. Rnf43 is mutated in subsets of human cancers of the colon, pancreas, stomach, ovary, and liver, while Znrf3 is mutated in adrenocortical carcinoma and osteoblastoma. Indeed, when both genes are mutated simultaneously in small intestinal stem cells in mice, tumors arise within a few weeks. Treatment of mice carrying RZ
−/−
intestinal neoplasia with a small molecule Wnt secretion inhibitor strongly inhibited growth, while adjacent normal crypts remained intact. These results establish that paracrine Wnt secretion is an essential driver of RZ
−/−
tumor growth and imply that a therapeutic window exists for the use of porcupine inhibitors for RZ-mutant cancers.
Responses of Coastal Largemouth Bass to Episodic Hypoxia
Authors: Brown Daniel T. , Aday D. Derek , Rice James A.
Published: May 2015

The river systems inhabited by coastal populations of Largemouth Bass Micropterus salmoides in North Carolina and along the Atlantic and Gulf coast regions exhibit episodic (i.e., several times per year) fluctuations in environmental conditions (e.g., dissolved oxygen [DO]). Laboratory studies have documented the effects of low DO (hypoxia) on Largemouth Bass, yet few field studies have examined these effects in open systems. The objective of this study was to determine the effects of episodic hypoxia on Largemouth Bass distribution, survival, and feeding success in an open coastal system. We collected 45 Largemouth Bass from four tributaries of the Chowan River and tagged them with acoustic transmitters. Fish movements were monitored using active tracking and passive receivers, and these data were compared with DO levels recorded in the tributaries and main‐stem Chowan River. We found that tagged Largemouth Bass exhibited avoidance behavior at DO concentrations below 1.8 mg/L, with some seeking higher DO in the main stem or near tributary mouths during hypoxic events in the tributaries. The natural mortality rate of Largemouth Bass was low compared with rates reported in other studies, indicating that Largemouth Bass in coastal systems are able to survive hypoxic events. Analysis of stomach contents collected during hypoxic and non‐hypoxic periods indicated that Largemouth Bass had less food in their stomachs under hypoxic conditions; however, the CPUE (fish/h of pedal time) of potential prey fishes was not lower during hypoxic periods relative to non‐hypoxic periods, and thus a change in foraging opportunities did not appear to drive Largemouth Bass movement.
Enhanced secretion of natto phytase by Bacillus subtilis
Authors: Tsuji Shogo , Tanaka Kosei , Takenaka Shinji , Yoshida Ken-ichi
Published: May 2015

Phytases comprise a group of phosphatases that trim inorganic phosphates from phytic acid (IP6). In this study, we aimed to achieve the efficient secretion of phytase by Bacillus subtilis. B. subtilis laboratory standard strain 168 and its derivatives exhibit no phytase activity, whereas a natto starter secretes phytase actively. The natto phytase gene was cloned into strain RIK1285, a protease-defective derivative of 168, to construct a random library of its N-terminal fusions with 173 different signal peptides (SPs) identified in the 168 genome. The library was screened to assess the efficiency of phytase secretion based on clear zones around colonies on plates, which appeared when IP6 was hydrolyzed. The pbp SP enhanced the secretion of the natto phytase most efficiently, i.e. twice that of the original SP. Thus, the secreted natto phytase was purified and found to remove up to 3 phosphates from IP6.
Unconditional love? Exploring hometown effect in Stalin’s birthplace
Authors: Kabachnik Peter , Gugushvili Alexi
Published: May 2015

This article explores the impact of spatial location – place – on people’s attitudes by examining whether support for Stalin is concentrated in his birthplace: Gori, Georgia. Using a variety of multivariate statistical methods, including propensity score-matching, we examine a recent survey indicating high levels of admiration for Stalin in his home country. We explore two main questions: First, is there a “hometown effect” – do people in Gori love Stalin unconditionally because they came from the same place? Second, is Gori so exceptional from the rest of Georgia? We conclude that there is indeed a stronger level of support for Stalin in Gori, but when shifting scales and looking within the category, we find that the highest admiration stems from the town’s rural outskirts.
Positroids and non-crossing partitions
Authors: Ardila Federico , Rincón Felipe , Williams Lauren
Published: May 2015

We investigate the role that non-crossing partitions play in the study of positroids, a class of matroids introduced by Postnikov. We prove that every positroid can be constructed uniquely by choosing a non-crossing partition on the ground set, and then placing the structure of a connected positroid on each of the blocks of the partition. This structural result yields several combinatorial facts about positroids. We show that the face poset of a positroid polytope embeds in a poset of weighted non-crossing partitions. We enumerate connected positroids, and show how they arise naturally in free probability. Finally, we prove that the probability that a positroid on

[
n
]

[n]

is connected equals

1

/

e
2

1/e^2

asymptotically.
The cone spanned by maximal Cohen-Macaulay modules and an application
Authors: Chan C-Y. , Kurano Kazuhiko
Published: May 2015

The aim of this paper is to define the notion of the Cohen- Macaulay cone of a Noetherian local domain

R
R

and to present its applications to the theory of Hilbert-Kunz functions. It has been shown by the second author that with a mild condition on

R
R

, the Grothendieck group

G
0

(
R
)

¯

\overline {G_0(R)}

of finitely generated

R
R

-modules modulo numerical equivalence is a finitely generated torsion-free abelian group. The Cohen-Macaulay cone of

R
R

is the cone in

G
0

(
R
)

¯

R

\overline {G_0(R)}_{\mathbb R}

spanned by cycles represented by maximal Cohen-Macaulay modules. We study basic properties on the Cohen-Macaulay cone in this paper. As an application, various examples of Hilbert-Kunz functions in the polynomial type will be produced. Precisely, for any given integers

ϵ
i

=
0
,
±
1

\epsilon _i = 0, \pm 1

(

d

/

2
>
i
>
d

d/2 > i > d

), we shall construct a

d
d

-dimensional Cohen-Macaulay local ring

R
R

(of characteristic

p
p

) and a maximal primary ideal

I
I

of

R
R

such that the function

ℓ
R

(
R

/

I

[

p
n

]

)

\ell _R(R/I^{[p^n]})

is a polynomial in

p
n

p^n

of degree

d
d

whose coefficient of

(

p
n

)
i

(p^n)^i

is the product of

ϵ
i

\epsilon _i

and a positive rational number for

d

/

2
>
i
>
d

d/2 > i > d

. The existence of such ring is proved by using Segre products to construct a Cohen-Macaulay ring such that the Chow group of the ring is of certain simplicity and that test modules exist for it.
The Sato-Tate law for Drinfeld modules
Authors: Zywina David
Published: May 2015

We prove an analogue of the Sato-Tate conjecture for Drinfeld modules. Using ideas of Drinfeld, J.-K. Yu showed that Drinfeld modules satisfy some Sato-Tate law, but did not describe the actual law. More precisely, for a Drinfeld module

ϕ
\phi

defined over a field

L
L

, he constructs a continuous representation

ρ
∞

:

W
L

→

D
×

\rho _\infty \colon W_L \to D^\times

of the Weil group of

L
L

into a certain division algebra, which encodes the Sato-Tate law. When

ϕ
\phi

has generic characteristic and

L
L

is finitely generated, we shall describe the image of

ρ
∞

\rho _\infty

up to commensurability. As an application, we give improved upper bounds for the Drinfeld module analogue of the Lang-Trotter conjecture.
xHeinz: an algorithm for mining cross-species network modules under a flexible conservation model
Authors: El-Kebir Mohammed , Soueidan Hayssam , Hume Thomas , Beisser Daniela , Dittrich Marcus , Müller Tobias , Blin Guillaume , Heringa Jaap , Nikolski Macha , Wessels Lodewyk F. A. , Klau Gunnar W.
Published: May 2015

Motivation: Integrative network analysis methods provide robust interpretations of differential high-throughput molecular profile measurements. They are often used in a biomedical context—to generate novel hypotheses about the underlying cellular processes or to derive biomarkers for classification and subtyping. The underlying molecular profiles are frequently measured and validated on animal or cellular models. Therefore the results are not immediately transferable to human. In particular, this is also the case in a study of the recently discovered interleukin-17 producing helper T cells (Th17), which are fundamental for anti-microbial immunity but also known to contribute to autoimmune diseases.

Results: We propose a mathematical model for finding active subnetwork modules that are conserved between two species. These are sets of genes, one for each species, which (i) induce a connected subnetwork in a species-specific interaction network, (ii) show overall differential behavior and (iii) contain a large number of orthologous genes. We propose a flexible notion of conservation, which turns out to be crucial for the quality of the resulting modules in terms of biological interpretability. We propose an algorithm that finds provably optimal or near-optimal conserved active modules in our model. We apply our algorithm to understand the mechanisms underlying Th17 T cell differentiation in both mouse and human. As a main biological result, we find that the key regulation of Th17 differentiation is conserved between human and mouse.

Availability and implementation: xHeinz, an implementation of our algorithm, as well as all input data and results, are available at http://software.cwi.nl/xheinz and as a Galaxy service at http://services.cbib.u-bordeaux2.fr/galaxy in CBiB Tools.

Contact:  gunnar.klau@cwi.nl

Supplementary information:  Supplementary data are available at Bioinformatics online.
Early post-settlement mortality of the scallop Pecten fumatus and the role of algal mats as a refuge from predation
Authors: Mendo T. , Lyle J. M. , Moltschaniwskyj N. A. , Semmens J. M.
Published: May 2015

Early post-settlement mortality is one of the main processes determining distribution and abundance patterns of marine benthic invertebrates. Most scallops have an attached phase as spat before they release the byssus and move onto the soft sediments. Thus, spat differ from other stages of life in their use of microhabitat, lack of mobility, and therefore in their vulnerability to mortality processes such as predation. However, the contribution of predation to explain levels of mortality experienced by spat and early juvenile scallops is unknown. Complex habitats such as seagrasses and algae provide a substrate upon which spat can attach and might confer an advantage as a refuge from predation. This study investigates the contribution of early post-settlement predation on abundance of Pecten fumatus and determines the role of the algae Hincksia sordida as a refuge from predation. Data were collected using field observations, a predator exclusion experiment, and tethering techniques. Mortality of up to 85% during the first weeks after settlement appeared to have prevented the establishment of an adult population at our study site. Mats of the macroalgae H. sordida provided a settlement substrate for P. fumatus spat. However, increased algal biomass did not provide greater protection from predation to juvenile scallops than lower algal biomass. Our study suggests that prey survival in submersed vegetation is likely to be dynamic among years, and affected by prey behaviour and density as well as the characteristics of the submerged vegetation.
Women Skating on the Edge: Marketplace Performances as Ideological Edgework
Authors: Thompson Craig J. , Üstüner Tuba
Published: May 2015

This study analyzes the marketplace performances that are enacted in the field of women’s flat track roller derby using the theoretical lens of gender performativity. Rather than treating the roller derby field as an autonomous enclave of gender resistance, this study focuses on the interrelationships between derby grrrls’ resignifying performances of femininity and the gender constraints that have been naturalized in their everyday lives. The market-mediated nature of derby grrrls’ ideological edgework enables them to challenge orthodox gender boundaries, without losing sociocultural legitimacy. This analysis casts new theoretical light on the gendered habitus and reveals key differences to the outcomes that would follow from Bourdieusian assumptions about the deployment of cultural capital in zero-sum status competitions. The concept of ideological edgework also presents a theoretical alternative to critical arguments, such as the commodity feminism thesis, that assume an inherently paradoxical and, ultimately co-opting, relationship exists between practices of countercultural resistance and marketplace performances. We further argue that ideological edgework redresses some of the conceptual ambiguities that can lead gender researchers to conflate gender performativity with social performances.
Conventional echocardiography—basic principles
Authors: Hagendorff Andreas
Published: May 2015

The transthoracic and transooesophageal documentation is the base of understanding and interpretation of sonographic findings. Practical and technical skills and a standardized acquisition of an echocardiographic image dataset make it possible to compare examinations due to better reproducibility. Standardization is also necessary to make diagnoses correctly and to objectify changes of the cardiovascular state. Despite the wide range of textbooks in the literature, there are limited user-oriented instructions for echocardiography. Thus, the present chapter starts by describing the practical aspects of transducer holding and its handling in transthoracic, as well as transooesophageal, echocardiography. Then, the reader is familiarized with the standard documentation of grey-scale 2D imaging, colour-coded imaging, and spectral Doppler imaging according to the actual international guidelines and recommendations. Illustrations of all important sectional planes are given. In addition, schemata for understanding special views, as well as for incorrect documentation, are given. At the end, a table of standard values and a table of cineloops and spectra belonging to a standardized investigation in echocardiography are given.
Cardiac CT—basic principles
Authors: Cademartiri Filippo , Maffei Erica , Arcadi Teresa , Catalano Orlando , Krestin Gabriel
Published: May 2015

Cardiac CT is a fast-developing technique. In 10 years it developed from an investigative tool into a clinical reality. The technology drive has been the key to success for this technique, which is to date the only non-invasive clinical tool for coronary angiographic assessment. Technical background is quite complex and the newer solutions are aiming at reducing the scan time and the radiation dose while improving temporal resolution, contrast resolution, and ultimately image quality. The key technical development has been in late 1990: the introduction of ECG triggering/gating techniques. Spatial resolution has also been improved, reaching sub-millimetre performance. The latest innovations provide fast coverage with >64 slice detectors, high spatial resolution with 0.5-mm slice thickness, high temporal resolution with <100 ms in hardware, and higher contrast resolution with the forthcoming dual-energy solutions.
New technical developments in cardiac CT
Authors: Achenbach Stephan
Published: May 2015

Computed tomography (CT), in the context of cardiac imaging, faces numerous challenges. The heart is a complex, three-dimensional organ, which moves very rapidly and has small dimensions. Especially the coronary arteries, the main target of cardiac CT imaging, are difficult to visualize by any non-invasive technique. Technology progress has made the use of CT for cardiac and coronary diagnosis possible. For selected applications, including ruling out coronary artery stenoses in low-risk individuals, CT has become a clinical tool. The technical progress of cardiac CT, and especially coronary CT angiography, is continuous and rapid. One major aim is to improve image quality and broaden the applicability of coronary CT angiography, while at the same time achieving lower radiation doses. The other major aim is to extract more than purely anatomic information out of the dataset and to complement the information in luminal narrowing with information on downstream ischaemia.
Aortic valve stenosis
Authors: Baumgartner Helmut , Donal Erwan , Orwat Stefan , Schmermund Axel , Rosenhek Raphael , Maintz David
Published: May 2015

Echocardiography is the method of choice for the diagnosis, assessment of morphology, and aetiology, as well as quantification of aortic valve stenosis. It permits the additional evaluation of the consequences on left ventricular size and, function, wall thickness, mitral valve (functional regurgitation).Haemodynamic assessment can be performed by Doppler echocardiography providing transvalvular gradients and valve areas can be determined by the continuity equation. Recently, MR and CT imaging have gained importance for assessment of valve morphology, ventricular function, and associated aortic disease. In current practice their role in quantifying severity of valve stenosis, however, remains limited. It is important to be aware of the specific limitations and pitfalls of the various measurements. Final judgement should be based on an integrated approach involving all available information. Finally, imaging techniques provide important prognostic information in aortic valve stenosis and have a fundamental impact on the decision making process in clinical practice.
Valvular heart disease: mitral valve stenosis
Authors: Brochet Eric , Gonçalves Alexandra
Published: May 2015

Rheumatic fever is still the predominant aetiology of mitral stenosis (MS) and full recognition and comprehensive assessment of valve morphology is fundamental for the treatment strategy. Echocardiography is the main method to diagnose and assess MS severity and consequences. The evaluation of morphology uses 2-dimensional (2D) and 3D echocardiography, while the severity classification depends on an integrative approach, combining all echocardiographic and Doppler parameters. Lately, cardiac magnetic resonance imaging (MRI) and multi-slice computed tomography (MSCT) are increasing adjuncts to echocardiography, but the experience in MS is still limited. This chapter describes the role of echocardiography, MRI, and MSCT in quantifying mitral stenosis and discusses the imaging part in decision-making and in the assessment of prognosis. Finally, we present an overview of echocardiography during percutaneous mitral commissurotomy.
MDCT and detection of coronary artery disease
Authors: Achenbach Stephan
Published: May 2015

Coronary CT angiography (coronary CTA) with multi-detector row CT (MDCT) systems permits visualization of the coronary arteries and detection of stenoses. Image quality depends on a low and stable heart rate, so patients need to be selected and adequately prepared. Due to a very high negative predictive value, coronary CTA is useful to rule out coronary artery stenosis, especially in low-to-intermediate risk patients with stable or acute chest pain. Imaging of patients with coronary artery stents and patients after bypass surgery is challenging and only in selected situations considered appropriate. Coronary CTA can visualize non-stenotic coronary atherosclerotic plaque, the presence and extent of which is associated with cardiovascular events, but there is no indication to perform coronary CTA for screening of asymptomatic individuals at low-intermediate risk. Coronary calcium, on the other hand, has a well-established predictive value and can be considered to improve risk stratification in asymptomatic individuals with a low to intermediate cardiovascular risk profile.
Evaluation of left ventricular systolic function and mechanics
Authors: Hoffmann Rainer , Colonna Paolo
Published: May 2015

Analysis of left ventricular (LV) systolic function is the most frequent indication to perform echocardiography and an integral part of cardiac magnetic resonance (CMR) or radionuclide studies. Visual estimation of LV function may be supplemented by quantitative analysis of 2D images to obtain parameters of global or regional function. Administration of contrast agents to improve identification of myocardium–blood interface has been demonstrated to improve the reproducibility of 2D-echocardiography-based analysis of LV function and should be applied in cases of insufficient endocardial border definition (more than two LV segments not adequately visualized). 2D-echocardiography-based analysis of LV volumes results in underestimation of end-systolic and end-diastolic LV volumes compared to CMR. 3D-echocardiography results in significantly less volume underestimation and higher accuracy in the analysis of ejection fraction. Analysis of regional wall motion is mainly based on subjective visual assessment, which is limited by significant inter-observer variability. Doppler tissue imaging and speckle tracking echocardiography have become validated methods for quantitative analysis of regional LV function. Similarly, tagging, strain-encoded cardiac magnetic resonance (SENC) and feature tracking are modalities to quantify regional LV function based on CMR. Echocardiography should be used as a primary technique to assess systolic LV function as it is the cheapest, widely available and can be applied without the use of ionizing radiation or nephrotoxic contrast material. CMR has become the clinical gold standard for quantification of LV function and may be applied if other information achievable best by CMR is required. Similarly, nuclear techniques should be applied to assess LV function only if simultaneous assessment of myocardial perfusion is requested.
Evaluation of diastolic LV function
Authors: Sutter Johan De , Vanoverschelde Jean-Louis J.
Published: May 2015

The evaluation of diastolic function in patients with reduced (HFREF) or preserved (HFPEF) left ventricular (LV) ejection fraction is important as it carries both diagnostic and prognostic information. In daily practice, this is most frequently done by standard echocardiographic techniques, including the evaluation of LV mass and LA volumes, as well as transmitral and pulmonary venous PW Doppler, CW Doppler for evaluation of the IVRT, and tissue Doppler imaging of the septal and lateral annular velocities. This permits grading the severity of diastolic dysfunction, which is related to outcome and may be used to estimate LV filling pressures. The latter needs further validation, especially in patients with HFPEF. Newer echocardiographic and cardiac magnetic resonance techniques, including myocardial deformation measurements during diastole, LV twist and untwisting, and parameters of left atrial function, are promising and will hopefully in the future help clinicians to make a more precise evaluation of diastolic function and filling pressures in heart failure patients.
Nuclear imaging and multi-detector computed tomography to assess viability
Authors: Perrone-Filardi Pasquale , Gerber Bernhard L.
Published: May 2015

Although recent trials have questioned whether revascularization of myocardial viability benefits survival of patients with chronic ischaemic heart disease, evaluation of myocardial viability by cardiac imaging still plays an important role in clinical practice for decision-making and selection of therapeutic strategies for patients with ischaemic and non-ischaemic left ventricular (LV) dysfunction. Application of cardiac imaging for viability assessment follows distinct pathophysiological approaches, namely regional assessment of perfusion by either single-photon emission computed tomography (SPECT) or positron emission tomography (PET), or regional assessment of perfusion and metabolism by PET, or verification of residual contractile reserve in dysfunctional myocardium using dobutamine stimulation, or direct visualization of necrotic myocardium by magnetic resonance imaging (MRI) or multi-detector computed tomography (MDCT). For predicting the recovery of regional or global LV systolic function at rest, nuclear techniques (PET and SPECT) demonstrate very high sensitivity but reduced specificity, which in clinical terms translates into overestimation of potential for recovery of systolic function, whereas an opposite behaviour is reported by techniques assessing contractile reserve. MDCT, like MRI, directly evaluates the presence of necrotic tissue using late enhancement (LE) after injection of a contrast agent. Although at present time no sufficient clinical experience has been reported, MSCT has the appealing potential for a comprehensive anatomic and tissue characterization within a single test.
Imaging cardiac innervation
Authors: Flotats Albert , Carrió Ignasi
Published: May 2015

Imaging cardiac autonomic nervous system has shown to be of value in the assessment of patients with different cardiac disorders, especially in those with heart failure (HF), where it has an independent prognostic value and provides a potential tool for improving patient management. Excellent reviews on cardiac autonomic imaging have been recently published. This chapter updates the subject with inclusion of novel data, highlighting the use of innervation imaging for monitoring therapy in patients with HF.
Cardiac resynchronization therapy: selection of candidates
Authors: Delgado Victoria , Bax Jeroen J.
Published: May 2015

Cardiac resynchronization therapy (CRT) is an established treatment for heart failure patients who remain symptomatic despite optimal medical treatment, with left ventricular ejection fraction <35% and QRS complex with left bundle branch block morphology or duration ≥150 ms. Non-invasive imaging modalities contribute in the evaluation and selection of patients who are candidates for CRT. Evaluation of left ventricular mechanics and dyssynchrony, extent and location of myocardial scar and cardiac venous anatomy are important to estimate the likelihood of favourable response to CRT. This chapter will review the ‘why and how’ to assess cardiac dyssynchrony, myocardial scar, and cardiac venous anatomy, prior to CRT implantation.
Echocardiography for advanced extracorporeal support
Authors: Price Susanna , Canivet Jean-Luc
Published: May 2015

Extracorporeal circuits are increasingly used to support critically ill patients with severe cardiac and/or respiratory failure. They may be used as a bridge to recovery, transplantation, decision for further intervention, or, in a very few patients with cardiac failure, as destination therapy. Although echocardiography for extracorporeal support is highly specialist, certain key principles apply. First, extracorporeal support is not a treatment per se, but rather a supportive therapy whilst awaiting resolution of the underlying pathological process. Thus echocardiography has a vital role in excluding any potentially treatable underlying cause for cardiorespiratory failure. Second, echocardiography is required to determine the requirement for right and/or left ventricular support, the level of support required, and assessing the ability of the right and left ventricles to support the extracorporeal circuit. This demands that the practitioner understands the different types of circuit, and the load that each will place on the heart. Third, echocardiography is mandatory to exclude cardiovascular contraindications to initiation of support. Echocardiography subsequently has a vital role in its successful implementation, including confirming/guiding correct cannula placement, ensuring the goals of support are met, detecting complications, and assessing tolerance to assistance. Finally, in patients requiring extracorporeal cardiac support, various echocardiographic parameters have been proposed to be used in conjunction with clinical and haemodynamic assessment in order to attempt to predict those patients who can be successfully weaned.
Infiltrative cardiomyopathy
Authors: Selvanayagam Joseph B. , Joseph Majo , Karamitsos Theodoros , Neubauer Stefan
Published: May 2015

Infiltrative cardiomyopathy can result from a wide spectrum of both inherited and acquired conditions with varying systemic manifestations. They usually portend an adverse prognosis, although in rare instances (e.g. Fabry’s disease) early diagnosis can result in potentially curative treatment. Cardiac amyloid remains the archetypal infiltrative cardiomyopathy and is discussed in most detail in this chapter. Non-invasive imaging modalities, principally echocardiography and cardiovascular magnetic resonance, play a pivotal role in the early diagnosis and management of all types of infiltrative cardiomyopathy.
Dilated cardiomyopathy
Authors: Germans Tjeerd , Lombardi Massimo , Neglia Danilo , Nihoyannopoulos Petros , van Rossum Albert C.
Published: May 2015

Dilated cardiomyopathies either familial/genetic or non-familial/non-genetic in origin are characterized by dilatation of one or both ventricles and systolic dysfunction. The modern imaging techniques allow assessment of the primary myocardial defect as abnormalities in the structural, mechanical, metabolic, and perfusion patterns. The diagnostic and the prognostic role of the three most used imaging modalities (echocardiography, nuclear technologies, and cardiac magnetic resonance imaging) are discussed with the purpose of integrating the specific cardiac characteristics provided by each of them.
Other genetic and acquired cardiomyopathies
Authors: Nihoyannopoulos Petros , Elliott Perry , Captur Gaby
Published: May 2015

The right ventricle may be the seat of ventricular tachycardia of left bundle branch block pattern. Recent interest has centred on its pathophysiology because early reports suggested that an apparent absence of gross organic heart disease indicated a more favourable prognosis. The term ‘arrhythmogenic right ventricular cardiomyopathy’ was first proposed in 1977 by Fontaine et al. when he reported right ventricular tachycardia associated with right-sided structural disorders. Although ARVC/D is a cardiomyopathy affecting primarily the right ventricle (RV), the left ventricle (LV) is also affected in many patients. It is a heterogeneous group of conditions characterized by right ventricular dysfunction and dilatation from very subtle abnormalities located at the RV to a most extensive RV and LV dysfunction.
Constrictive pericarditis
Authors: Garot Jérôme , Rademakers Frank
Published: May 2015

The diagnosis of constrictive pericarditis (CP) generally requires both the demonstration of an appropriate physiology and evidence of pericardial thickening. Differential diagnosis in pericardial disease remains difficult and challenging to the clinician. The pathophysiologic characteristics of the various pericardial syndromes can be studied with different imaging modalities, but it is crucial to register morphology, function and flow during the different phases of the respiratory cycle. When a discrepancy exists between clinical findings and hemodynamic evaluation with imaging, multiple modalities should be combined and, if a very low or very high atrial pressure is suspected, an intervention to increase or lower this pressure can be required to unmask characteristic findings during respiration with respect to ventricular interdependence.
Cardiac masses and tumours
Authors: Buser Peter , Buck Thomas , Plicht Björn
Published: May 2015

Cardiac tumours represent a rare but important cause of morbidity and mortality in clinical cardiology and are often challenging in diagnostic cardiac imaging. There is a broad spectrum of differential diagnosis for cardiac masses. This chapter is mainly focused on the diagnosis of primary and secondary cardiac tumours and intra-cardiac thrombi. Diagnostic imaging of cardiac tumours provides important clinical decision-making information, such as origin, size, extension, morphology, and mobility of the tumour, involvement of cardiac chambers, valves, myocardium and pericardium, invasiveness, vascularization, and tissue characterization. Echocardiography is usually the first imaging modality providing high sensitivity in detecting cardiac masses, particularly by transoesophageal approach, and detailed analysis of mass characteristics by the use of different imaging modalities, including 3D imaging, tissue Doppler imaging, and contrast imaging.
The role of echocardiography in adult congenital heart disease
Authors: Mertens Luc , Friedberg Mark K.
Published: May 2015

Congenital malformations of the heart affect at least 1% of newborn infants. Without intervention, the prognosis for more complex forms is poor. Over the last few decades advances in paediatric cardiology and cardiac surgery have significantly improved patient management, and the majority of patients now survive into adulthood. This has led to new challenges as increasing numbers of adult patients with congenital heart disease transition into the care of adult cardiac services. Caring for these patients requires expert knowledge and a new subspecialty of adult congenital heart disease (CHD) has emerged. This patient population also has specific imaging requirements due to variability in morphology and hemodynhaemodynamics.
The roles of CMR and MSCT in adult congenital heart disease
Authors: Kilner Philip , Nicol Ed , Rubens Michael
Published: May 2015

Both CMR and MSCT give almost unrestricted access to intra-thoracic structures, whereas ultrasonic access may be limited in ACHD patients. MSCT, generally using intravascular contrast, gives superior spatial resolution more rapidly than CMR, although the radiation dose is a concern in younger patients who may require repeated studies. MSCT gives better visualisation of epicardial coronary arteries and small collateral vessels, and can show conduit calcification or stent location clearly. It provides an alternative to CMR in patients with a pacemaker or ICD. CMR offers unrivalled versatility of acquisition methods without ionizing radiation, enabling measurements of biventricular function, flow, myocardial viability, angiography and more. A dedicated CMR service should be available in a centre specializing in ACHD care. Appropriate understanding is needed for the evaluation of congenitally and surgically altered circulatory function, for example after Fontan operations, surgery for transposition of the great arteries or tetralogy of Fallot.
Role of echocardiography
Authors: Fernández-Golfín Covadonga , Zamorano José L.
Published: May 2015

Aortic aneurysms and aortic dissection are relatively frequent entities and their prognosis is sometimes fatal. Transthoracic and transoesophageal echocardiography are two of the main diagnostic tools for diagnosis, prognostic evaluation and surgical assessment. In this chapter, the potential use of echocardiography for patients with suspected or demonstrated aortic aneurysm or dissection will be discussed.
Role of magnetic resonance imaging in aortic disease
Authors: Evangelista Arturo , Garot Jérôme
Published: May 2015

MRI is a non-invasive imaging technique that permits the most comprehensive study of aortic diseases. It offers morphological, functional and biochemical information. Conventional ECG-gated spin-echo imaging, cine gradient-echo and contrast-enhanced 3D MR angiography have earned MRI the reputation of being the ideal tool for evaluating the aorta. The phase-contrast imaging technique enables the assessment of flow in the great vessels. MRI can be used to define the location and extent of aneurysms, dissections and aortic wall ulceration. This is the best technique to demonstrate areas of wall thickening related to aortitis or intramural haematoma. MRI may also be used as a tool to study aortic physiology by assessment of elastic aortic properties, stiffness and aortic wall shear stress. MRI is particularly useful in patients with either contraindications to iodinated contrast material or in those with known aneurysms who require sequential follow-up.
Diagnosis in Psychiatry
Authors: Paris Joel
Published: May 2015

Diagnosis in psychiatry lacks precision because disorders have fuzzy boundaries with each other and with normality. Validity is problematic because diagnosis is entirely based on signs and symptoms; there are no biological markers for any of the major mental disorders. Clinicians can under-diagnose or overdiagnose disorders, but the problem of overdiagnosis is more prevalent and more problematic. At the present state of knowledge, psychiatry does not need hundreds of diagnoses, only a few of which have established validity. Overdiagnosis is an attempt to short-circuit a process of scientific discovery that will require many more decades of research.
Science, Philosophy, and Diagnosis
Authors: Paris Joel
Published: May 2015

Mental disorders need not be seen as “real” in the same way as medical diagnoses. Current categories of mental disorder are not well validated, and can best be considered as heuristics. Overdiagnosis ignores these limitations, sometimes leading to diagnostic epidemics in which many different phenomena are seen as belonging to the same category. The use of DSM-5 as a gold standard has also distorted psychiatric epidemiology, which has been based on syndromal definitions rather than empirically validated categories. These concepts have made it all too easy to diagnose almost everyone with some form of mental disorder.
Where Do We Go From Here?
Authors: Paris Joel
Published: May 2015

The problem of overdiagnosis reflects physician biases, and the wish to explain complex clinical presentations. Overdiagnosis has also become part of a broader cultural trend in which all human problems are seen as requiring medical treatment. Evidence-based practice, accompanied by a tolerance of uncertainty, can help to reduce the frequency of this problem. The diagnostic manuals of the future will probably not look very much like DSM-5. I expect that they will be based on a deeper and more thorough understanding of disease. But that will take many decades, and we have to remain humble and patient.