bluuebunny/crossref_metadata_2025 huggingface dataset:
Simultaneous and Sequential Qualitative Mixed Method Designs
Authors: Morse Janice M.
Published: April 2010

Mixed methods, defined as one complete method (as the core project) plus a different simultaneous and sequential supplemental strategy, have been well explicated for combining the most difficult designs—that is, qualitative and quantitative methods. However, experts in qualitative inquiry have relatively ignored the issues that occur while describing qualitative simultaneous and sequential designs in which both components are qualitative. In this article, the author argues that qualitative mixed method designs introduce many of the incompatibility problems of mixed method design that use qualitative and quantitative components. Various qualitatively driven mixed method designs are presented. Then, using an armchair walkthrough, QUAL- qual designs are contextualized within a hypothetical project of breaking bad news, and several examples of QUAL- qual mixed method designs are discussed.
Notes for Working With Detachment
Authors: Krueger Mark
Published: April 2010

The author shares his notes from writers, thinkers, poets, filmmakers, artists, and performers who worked with a sense of detachment. In addition to what he learns from reflective research, he uses these notes to help write sketches about youth and youth work. His goal is to create work that stands by itself. This allows him to see his experiences more clearly. To exemplify, he presents sketches from his collection Of Youth, an exploration of his youth unfolding over time.
A Critical Review of ADHD Diagnostic Criteria: What to Address in the DSM-V
Authors: Bell Allison S.
Published: April 2010

ADHD is an impairing psychological disorder that predominantly affects children, but also adults to a lesser extent. As a result, a considerable amount of research has been completed in recent years to better understand the nature of the disorder to best treat individuals experiencing symptoms of ADHD. Especially with the publication of the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) ( DSM-V) on the horizon, substantial empirical work has been analyzing current ADHD diagnostic criteria and what upcoming changes should be made. Among child and adult populations, adjusting or completely eradicating the age of onset criterion is well supported. With specifically adult populations, amending symptoms to be more developmentally and environmentally appropriate also appears necessary. Even though research additionally questions the state of ADHD subtypes (with both child and adult populations) and other general diagnostic issues (model for diagnosis and level of impairment), continued research is needed to better clarify what other changes should be made in the DSM-V and beyond.
Temporal dynamics of situated learning in organizations
Authors: Lervik Jon Erland , Fahy Kathryn M. , Easterby-Smith Mark
Published: April 2010

Situated learning theory posits that learning in organizations arises in the contexts and conditions of practical engagement, and time is an important dimension of activity and context of learning. However, time has primarily been conceptualized as an internal property of communities, buffered from social and organizational temporalities that shape rhythms of working and learning. This article examines how external temporalities affect situated learning through case studies of technical after-sales services. A situated learning perspective posits how new understandings are constructed from a broad assemblage of resources and relations. These resources and relationships are to a large extent governed by external temporalities that influence opportunities for learning through everyday work. We highlight temporal structures as an important mechanism guiding or obstructing the development of new understandings, and we conclude that a temporal perspective on situated learning holds important implications for practice and further research.
Disabled children’s services: how do we measure family-centred care?
Authors: Pickering Dawn , Busse Monica
Published: April 2010

Family-centred care has been defined as a philosophy of care where families are supported in their decision-making roles in an equal partnership with professionals. The research question was ‘How ‘‘family centred’’ do staff and parents perceive their work with disabled children and young people?’ A questionnaire, the Measure of Processes of Care for Service Providers (MPOC-SP), was used as a basis for designing focus groups and interview questions. Staff and parents took part in these and data were analysed using an editing approach. Staff described how they adapted their service to meet parental needs and empowered and enabled parents despite receiving no specific training in FCC. Parents spoke highly of the staff input and gave varied descriptions of the attributes they most valued, including feeling supported and being in an equal partnership. Investigation of the influence of focused FCC training on parental experiences is warranted.
PRIFAM: a shared experience leading to the transformation of everyone involved
Authors: Pelchat Diane
Published: April 2010

This article presents the PRIFAM, an interdisciplinary family intervention program co-constructed with parents of children with a disability. The PRIFAM’s theoretical foundations, clinical model of the adaptation/transformation process and tools have enabled professionals to conceptualize many years’ worth of research, clinical observations, and professional and personal experience. Through its relational foundations, the partnership forged between families and professionals contributes extensively to the adaptation of families and the well-being of professionals, by acknowledging their reciprocal resources and mutual competencies. The birth of a child with a disability triggers severe stress and plunges parents and families into a grieving process, but this process also leads to learning that generates transformation of the bereavement experience. A number of evaluative studies of the PRIFAM have demonstrated the importance of the close reciprocal relationship between research and clinical practice, which enables family intervention practices to evolve.
When the best become the rest: The interactive effect of premerger status and relative representation on postmerger identification and ingroup bias
Authors: Boen Filip , Vanbeselaere Norbert , Wostyn Piet
Published: April 2010

This experiment tested the combined impact of premerger status (low, high) and relative representation (low, high) on identification with a merged group and on bias expressed towards members of the merger partner. In phase 1, 111 university students were assigned to a premerger team of “inductive” thinkers. Premerger status was manipulated by informing participants that their team had performed worse or better than a deductionist team on a decision-making task. In phase 2, the participants’ premerger team was supposedly merged with this deductionist team to form a new merger team of analyst thinkers. Relative representation was manipulated by preserving either most or none of the characteristics of the premerger team in the new merger team. The results revealed a significant interaction between premerger status and relative representation on both postmerger identification and ingroup bias. Participants belonging to a high premerger status group confronted with a low relative representation reported less postmerger identification and more bias than participants in the other three conditions. Moreover, relative representation, but not premerger status, moderated the relation between postmerger identification and ingroup bias. More specifically, when relative representation was high, postmerger identification and ingroup bias were positively related. By contrast, when relative representation was low, postmerger identification and ingroup bias were negatively related. These results confirm the predictions based on the Ingroup Projection Model.
Believing shapes seeing: The impact of diversity beliefs on the construal of group composition
Authors: Homan Astrid C. , Greer Lindred L. , Jehn Karen A. , Koning Lukas
Published: April 2010

Previous research has suggested that diversity effects depend on how group members perceive their group’s composition. However, what determines how diversity is perceived is unclear. We argue that the way in which group members construe their group’s diversity is shaped by group members’ beliefs about the value in diversity. Focusing on groups with objective subgroups, we show in two studies that the more group members value diversity, the more likely they are to construe their diversity in terms of individual differences and the less likely they are to construe their diversity in terms of subgroups. We also show that diversity construal is only affected by diversity beliefs during intellectual tasks (where diversity matters), but not during physical tasks.
Does the correlation between self and ingroup/outgroup depend on group favorability?
Authors: Foroni Francesco , Pong Vivien , Rothbart Myron , Pearce Gale
Published: April 2010

There is considerable evidence that predictions about others’ behavior are anchored to comparable judgments about the self. There is also strong evidence that while self-judgments predict ingroup members’ behavior more strongly than outgroup members, the correlation between self and group remains positive for both ingroups and outgroups (Robbins & Krueger, 2005). The present study examined two related questions. First, could the differences in correlation between self and ingroup versus outgroup be attributed to differences in group favorability? Second, would a negative correlation between self and outgroup be found for intensely disliked outgroups? Using an idiographic design that assessed self—group correlations for ingroups and outgroups ranging in favorability from highly disliked to highly liked, we found: (1) group favorability did not explain ingroup—outgroup differences; and (2) there was no evidence for a negative correlation between self and outgroups, even highly disliked outgroups. Discrepancies with earlier research are discussed.
Effect of angiotensin-converting enzyme gene insertion/deletion polymorphism on steroid resistance in Egyptian children with idiopathic nephrotic syndrome
Authors: Saber-Ayad Maha , Sabry Samar , Abdel-Latif Inas , Nabil Hanaa , El-Azm Soheir Abo , Abdel-Shafy Sanaa
Published: April 2010

Introduction. The presence of the deletion (D) allele in the angiotensin-converting enzyme (ACE) gene has been reported as a probable genetic risk factor for idiopathic nephrotic syndrome (INS), but its role in determining resistance to steroid therapy remains to be evaluated.

Methods. Fifty-one patients were enrolled in the study and received oral steroids. The pattern of response to steroid therapy was determined. A group of 50 healthy adults served as a control group. The genotypes for ACE insertion (I)/D polymorphism were analysed using a PCR-based method.

Results. Twenty patients were steroid sensitive (SS) and 31 were non-SS. The presence of hypertension at presentation was significantly related to steroid unresponsiveness. Among the SS group, the frequencies of the II, ID, and DD genotypes of the ACE gene were 20% (n=4), 65% (n=13), and 15% (n=3), respectively, while the frequencies among the non-SS group were 19.4% (n=6), 74.2% (n=23), and 6.5% (n=2), respectively. The differences between the two groups were not statistically significant (Chi square=0.59).

Conclusion. The current study on Egyptian children with INS reveals no association between the ACE gene I/D polymorphism and clinical parameters, histological findings, and steroid resistance.
Review: Plasma renin and the incidence of cardiovascular disease
Authors: Meade Tom
Published: April 2010

Whether renin is involved in the onset of coronary heart disease (CHD) remains unclear. A case-control study in 1972, suggesting a causal association between renin and CHD, has now been followed by three prospective studies. One was based on 1,717 hypertensive subjects in a Work-Site Program in New York. The main results showed an increased risk of CHD the higher the renin level. A second study in occupational groups in North West London, UK, recruited 803 white men not selected according to blood pressure, and found no association.

A possible exception was in the minority of those with similar blood pressure levels to participants in the Work-Site Program, in whom the incidence of CHD was higher according to the renin level, but not significantly so. The third study was in Framingham Offspring and included 3,532 participants also not selected according to blood pressure. As in the UK study, there was no clear association between renin and risk of CHD in all participants, or in this study in those with raised blood pressure. The authors considered their results consistent with those of the UK study in finding “no association of renin with overall risk of CHD”. Besides the three epidemiological studies, dealing explicitly with renin, other studies in which it has been one of several variables considered have also not found convincing evidence of its involvement in CHD. There is, therefore, little support for the hypothesis that high renin levels increase the risk of CHD, with the possible but uncertain exception of those with raised blood pressure.
Wireless Intelligent Sensor and Actuator Network - A Scalable Platform for Time-synchronous Applications of Structural Health Monitoring
Authors: Sazonov Edward , Krishnamurthy Vidya , Schilling Robert
Published: April 2010

Wireless sensor networks have attracted attention as a possible solution for applications of periodic and continuous structural health monitoring. Ensuring synchronous data acquisition across wireless nodes in large networks of sensors spatially distributed on a structure is of critical importance for many methods of structural health monitoring, especially those based on analysis of vibration. In this article we present a novel Wireless Intelligent Sensor and Actuator Network (WISAN) addressing the issue of scalability for applications of structural health monitoring. We also present a novel time synchronization algorithm that can keep the synchronization error between any number of globally distributed sensors nodes less than ±23 μs. We show proof of stability for the time synchronization algorithm. We validate WISAN in laboratory experiments, testing the actual time synchronization between randomly selected sensors in a complex network. Finally, we validate WISAN in a field experiment by reconstructing mode shapes of a highway bridge.
Integrating Base Object Model Components into DEVS-based Simulation
Authors: Bin Chen  , Ronghua Zhong  , Vangheluwe Hans
Published: April 2010

The SISO standard Base Object Model (BOM) specification facilitates interoperability, re-usability, and composability of component models for simulation purposes. The common practice of constructing a BOM-based simulation system using the High-Level Architecture (HLA) does not, however, exploit the hierarchy of BOM components and hence limits re-usability. The Discrete EVent system Specification (DEVS) formalism has proven to be appropriate for hierarchical modeling and subsequent parallel and distributed simulation. In this paper we integrate the key part of the BOM, the component kernel, into a DEVS framework by mapping it onto atomic DEVS models. On the one hand, this precisely defines an automated mapping which fully conserves the wealth of information (such as hierarchy) present in BOMs. On the other hand, it allows for re-use of a plethora of theory, techniques and tools available for the DEVS formalism. If necessary, the DEVS models obtained through the integration can be optimized. A small case study of the take-off and landing of a plane demonstrates the increased re-usability compared to HLA-based approaches. This case study is also used to compare the performance of a BOM-based simulation system with the DEVS equivalent.
Genetic characterisation and structural analysis of the O-specific polysaccharide of Yersinia pseudotuberculosis serotype O:1c
Authors: De Castro Cristina , Kenyon Johanna J. , Cunneen Monica M. , Reeves Peter R. , Molinaro Antonio , Holst Otto , Skurnik Mikael
Published: April 2010

Many, but not all, of the current 21 serotypes of Yersinia pseudotuberculosis have been investigated with regard to the chemical structures of their O-specific polysaccharide (OPS) and the genetic basis of their biosynthesis. Completion of the genetics and structures of the remaining serotypes will enhance our understanding of the emerging relationship between genetics and structures within this species. Here, we present a structural and genetic analysis of the Y. pseudotuberculosis serotype O:1c OPS. Our results showed that this OPS has the same backbone as Y. pseudotuberculosis O:2b, but with a 3,6-dideoxy-D- ribo-hexofuranose (paratofuranose, Parf) side-branch instead of a 3,6-dideoxy-D-xylo-hexopyranose (abequopyranose, Abep). The 3'-end of the gene cluster is the same as for O:2b and has the genes for synthesis of the backbone and for processing the completed repeat unit. The 5'-end of the cluster consists of the same genes as O:1b for synthesis of Parf and a related gene for its transfer to the repeating unit backbone.
Three-dimensional spheroid cultures of A549 and HepG2 cells exhibit different lipopolysaccharide (LPS) receptor expression and LPS-induced cytokine response compared with monolayer cultures
Authors: Jian Liu  , Abate Wondwossen , Jinsheng Xu  , Corry David , Kaul Baksho , Jackson Simon K.
Published: April 2010

Lipopolysaccharide (LPS) is a potent modulator of pathogen-induced host inflammatory responses. Lipopolysaccharide signaling to host cells is correlated with the expression of well-characterized LPS receptors. We have developed three-dimensional (3-D) cell cultures (spheroids) that are more representative of in vivo conditions than traditional monolayer cultures and may provide novel in vitro models to study the inflammatory response. In this work, we have compared F-actin organization, LPS-induced pro-inflammatory cytokine response and LPS receptor expression between spheroid and monolayer cultures from A549 lung epithelial cells and HepG2 hepatocytes. Significant junctional F-actin was seen at the cell—cell contact points throughout the spheroids, while monolayer cells showed stress fibers of actin and more prominent F-actin localized at the cell base. A time course of cytokine release in response to LPS showed that A549 spheroids secreted persistently higher levels of interleukin (IL)-6 and IL-8 compared with monolayer cultures. Unlike monolayer cultures, HepG2 spheroids responded to LPS by releasing a significant level of IL-8. We identified a significant increase in the expression of CD14 and MD2 in these spheroids compared with monolayers, which may explain the enhanced cytokine response to LPS. Thus, we suggest that 3-D spheroid cell cultures are more typical of in vivo cell responses to LPS during the development of inflammation and would be a better in vitro model in inflammation studies.
Review: Defensins and cathelicidins in lung immunity
Authors: Tecle Tesfaldet , Tripathi Shweta , Hartshorn Kevan L.
Published: April 2010

Defensins were first identified in 1985 and are now recognized as part of a large family of antimicrobial peptides, divided into three categories: α-, β-, and θ-defensins. These defensin classes differ in structure, sites of expression and biological activities. Human α-defensins include peptides that are expressed primarily in neutrophils, whereas human β-defensins are widely expressed in epithelial cells, including those lining the respiratory tract. Defensins were first studied for their broad spectrum activity against bacteria, fungi and viruses; however, it is now clear that they also recruit inflammatory cells and promote innate and adaptive immune responses. Recent evidence shows that defensins have anti-inflammatory effects as well. Hence, defensins can participate in all phases of an immune response in the lung, including initial killing of pathogens and mounting — and resolution —- of an immune or inflammatory response. The cathelicidin, LL-37, is an antimicrobial peptide produced by neutrophils and respiratory epithelial cells that has similar roles in lung immunity as the defensins. A major challenge for the coming years will be to sort out the relative contributions of defensins and LL-37 to overall immune responses in the lung and to determine which of their many in vitro activities are most important for lung immunity.
Lipopolysaccharide induces raft domain expansion in membrane composed of a phospholipid-cholesterol-sphingomyelin ternary system
Authors: Nomura Kaoru , Maeda Masahide , Sugase Kenji , Kusumoto Shoichi
Published: April 2010

The molecular behavior and interaction of Re-type lipopolysaccharide (ReLPS) and phospholipids were investigated in two different types of model membrane systems, a pure phospholipid membrane consisting of 1,2-dielaidoyl-snglycero-3-phosphoethanolamine (DEPE) and a raft-forming membrane composed of equimolar DEPE, sphingomyelin (SM), and cholesterol (Chol) by solid-state NMR spectroscopy. A remarkable influence of ReLPS on the property of lipid bilayer was found by analyzing the 13C-NMR spectra. Namely, while both liquid-ordered (Lo) and liquid-disordered (Ld) phases co-exist in DEPE/SM/Chol, only the Lo phase is present in DEPE/SM/Chol/ReLPS. This clearly indicates that ReLPS induces expansion of the raft area in the raft-forming membrane. The 1H spin-lattice relaxation times in the rotating frame T 1ρH in the two different membranes, DEPE/ReLPS and DEPE/SM/Chol/ReLPS, indicate that the motion of DEPE is affected by the presence of ReLPS, Chol, and SM, and much faster than that of ReLPS in both membranes. The ReLPS in the raft-forming membrane, in particular, accelerated the movement of DEPE. Thus, this study shows the possibility that LPS induces the expansion of raft region and the rapid motion of the raft-forming membranes to favor molecular interactions in the animal cell membrane during innate immune recognition.
Review: Toll-like receptors and NOD-like receptors in pulmonary antibacterial immunity
Authors: Balamayooran Theivanthiran , Balamayooran Gayathriy , Jeyaseelan Samithamby
Published: April 2010

Lung diseases caused by bacteria are a leading cause of death in both immunocompromised and immunocompetent individuals as well as in children. Although neutrophil recruitment is critical to augment the host defence, excessive neutrophil accumulation results in life-threatening diseases, such as acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Therefore, it is important to modulate excessive neutrophil influx in ALI/ARDS to mitigate lung damage and mortality. A better understanding of the basic mechanisms underlying neutrophil influx is crucial to designing novel and innovative treatment strategies for ALI/ARDS. Recognition of bacteria in the lung is the critical first step leading to neutrophil influx. Pattern recognition receptors, such as Toll-like receptors and NOD-like receptors, play an important role in the recognition of bacterial pathogens. Understanding the molecular and cellular mechanisms associated with the recognition of bacterial pathogens by the host is critical for the development of effective therapeutic strategies to control parenchymal damage via modulating neutrophil accumulation in the lung.
Review: Mammalian peptidoglycan recognition proteins (PGRPs) in innate immunity
Authors: Dziarski Roman , Gupta Dipika
Published: April 2010

Peptidoglycan recognition proteins (PGRPs or PGLYRPs) are innate immunity proteins that are conserved from insects to mammals, recognize bacterial peptidoglycan, and function in antibacterial immunity and inflammation. Mammals have four PGRPs — PGLYRP1, PGLYRP2, PGLYRP3, and PGLYRP4. They are secreted proteins expressed in polymorphonuclear leukocytes (PGLYRP1), liver (PGLYRP2), or on body surfaces, mucous membranes, and in secretions (saliva, sweat) (PGLYRP3 and PGLYRP4). All PGRPs recognize bacterial peptidoglycan. Three PGRPs, PGLYRP1, PGLYRP3, and PGLYRP4 are directly bactericidal for both Gram-positive and Gram-negative bacteria and have no enzymatic activity, whereas PGLYRP2 is an N-acetylmuramoyl-L-alanine amidase that hydrolyzes bacterial cell wall peptidoglycan. Peptidoglycan recognition proteins influence host— pathogen interactions not only through their antibacterial or peptidoglycan-hydrolytic properties, but also through their pro-inflammatory and anti-inflammatory properties that are independent of their hydrolytic and antibacterial activities. The PGRPs likely play a role both in antibacterial defenses and several inflammatory diseases. They modulate local inflammatory responses in tissues (such as arthritic joints) and there is evidence for association of PGRPs with inflammatory diseases, such as psoriasis.
Regulatory role of natural killer (NK) cells on antibody responses to Brucella abortus
Authors: Ning Gao  , Jennings Paula , Yuhong Guo  , Yuan Dorothy
Published: April 2010

Our previous studies have indicated an important regulatory role for natural killer (NK) cells, a major constituent of the innate immune system in modulating antigen-specific responses. Herein, we have investigated the possible participation of these cells in regulating the polyclonal response as well. For these studies we have utilized heat-killed Brucella abortus (HKBA). Brucella abortus is a facultative intracellular bacterium that is pathogenic for both humans and animals. An outstanding feature of the infectious process is the rapid production of polyclonal antibodies, particularly of the IgG2c subclass, that bypasses the requirement for clonally specific antigen recognition. We report here that NK-cell depletion profoundly reduced the production of these polyclonal antibodies suggesting that activation of B cells by HKBA requires help from NK cells. This help may not be solely derived from NK-cell amplification of the cytokine circuit initiated by HKBA but may involve direct NK—B-cell interactions as suggested by results of in vitro analyses of NK induction of γ2a mRNA by B cells. These findings have therapeutic implications in that the induction of polyclonal Ig production may be more important for altering the chronic phase rather than the acute stage of infection by B. abortus.
Review: Collectins link innate and adaptive immunity in allergic airway disease
Authors: Ledford Julie G. , Pastva Amy M. , Wright Jo Rae
Published: April 2010

Although the lipoprotein complex of pulmonary surfactant has long been recognized as essential for reducing lung surface tension, its role in lung immune host defense has only relatively recently been elucidated. Surfactant-associated proteins A (SP-A) and D (SP-D) can attenuate bacterial and viral infection and inflammation by acting as opsonins and by regulating innate immune cell functions. Surfactant-associated protein A and D also interact with antigen-presenting cells and T cells, thereby linking the innate and adaptive immune systems. A recent study from our laboratory demonstrated that mice deficient in SP-A have enhanced susceptibility to airway hyper-responsiveness and lung inflammation induced by Mycoplasma pneumonia, an atypical bacterium present in the airways of approximately 50% of asthmatics experiencing their first episode, and further supports an important role for SP-A in the host response to allergic airway disease. Animal and human studies suggest that alterations in the functions or levels of SP-A and SP-D are associated with both infectious and non-infectious chronic lung diseases such as asthma. Future studies are needed to elucidate whether alterations in SP-A and SP-D are a consequence and/or cause of allergic airway disease.
Review: Gp-340/DMBT1 in mucosal innate immunity
Authors: Madsen Jens , Mollenhauer Jan , Holmskov Uffe
Published: April 2010

Deleted in Malignant Brain Tumour 1 (DMBT1) is a gene that encodes alternatively spliced proteins involved in mucosal innate immunity. It also encodes a glycoprotein with a molecular mass of 340 kDa, and is referred to as gp-340 (DMBT1gp340) and salivary agglutinin (DMBT1SAG). DMBT1gp340 is secreted into broncho-alveolar surface lining fluid whereas DMBTSAG is present in the saliva. The two molecules were shown to be identical and both interact with and agglutinate several Gram-negative and Gram-positive bacteria including Streptococcus mutans, a bacterium responsible for caries in the oral cavity. DMBT1gp340 interacts with surfactant proteins A and D (SP-D). DMBT1gp340 and SP-D can individually and together interact and agglutinate influenza A virus. DMBT1gp340 also binds to HIV-1 and facilitates transcytosis of the virus into epithelial cells. DMBT1 binds to a variety of other host proteins, including serum and secretory IgA, C1q, lactoferrin, MUC5B and trefoil factor 2 (TFF2), all molecules with involvement in innate immunity and/or wound-healing processes. Recent generation of Dmbt1-deficient mice has provided the research field of DMBT1 with a model that allows research to progress from in vitro studies to in vivo functional studies of the multifunctional proteins encoded by the DMBT1 gene.
Dronedarone: an emerging therapy for atrial fibrillation
Authors: Agabiti Rosei Enrico , Salvetti Massimo
Published: April 2010

Atrial fibrillation (AF) is a common arrhythmia, with a prevalence ranging from 0.1% to 9.0% at different ages, and is associated with increased cardiovascular events and mortality. A significant increase in the prevalence of the disease is expected to occur in the coming years as a consequence of the aging of the population and advances in the management of coronary artery disease and heart failure. Effective rhythm control may be difficult to obtain in a significant proportion of patients with AF. The limited efficacy and the possible adverse effects of antiarrhythmic drugs has led researchers to focus their attention on new molecules, in a search of compounds with antiarrhythmic efficacy and a more favourable safety profile. Among several new drugs developed for the management of AF, dronedarone, a benzofuran derivative that shares many of the antiarrhythmic properties of amiodarone, but with a more favourable safety profile, seems particularly promising. The drug is noniodinated, has less lipophilicity, reaches therapeutic concentrations over a shorter period of time and has lower tissue accumulation. Dronedarone, similarly to amiodarone, exhibits electrophysiologic characteristics of all 4 Vaughan Williams classes. Clinical studies have shown that dronedarone effectively reduces ventricular rate, may prevent or delay the recurrence of AF, and may reduce cardiovascular morbidity and mortality in patients with AF or atrial flutter. The drug has an overall good safety profile, in particular with low pulmonary and thyroid toxicity. An important exception is represented by patients with unstable haemodynamic conditions, in which the use of dronedarone has been found to be associated with an increase in mortality. Dronedarone has been recently approved for clinical use by the Food and Drug Administration and by the European Medicines Agency. Further results from trials and clinical use will better define the efficacy and safety profile of dronedarone in AF compared with other antiarrhythmic drugs and its role in the management of patients with AF.
Aliskiren versus ramipril in hypertension
Authors: Verdecchia Paolo , Angeli Fabio , Mazzotta Giovanni , Martire Paola , Garofoli Marta , Gentile Giorgio , Reboldi Gianpaolo
Published: April 2010

Aliskiren is an orally active direct renin inhibitor which inhibits the synthesis of angiotensin I by linking to active renin on a deep cleft of its molecular structure, the site of hydrolysis of the Leu10-Val11 bond of angiotensinogen. At variance with angiotensin-converting enzyme (ACE) inhibitors, aliskiren eliminates the main substrate for the ‘escape’ phenomenon (synthesis of angiotensin II from angiotensin I through alternative enzymatic pathways). The possibility that the antihypertensive effect of aliskiren differs from that of ACE inhibitors needs to be proved in specifically designed clinical trials. Over the past 2 years, three studies have been published which directly compared aliskiren with ramipril, in patients with hypertension. We made a pooled analysis of these studies. In order to avoid interference with additional drugs, analysis was restricted to trial periods when the two drugs were given as monotherapy. In each individual study, systolic blood pressure (BP) was slightly lower with aliskiren. Overall, systolic BP was lower with aliskiren than with ramipril (weighted mean difference between the treatments 1.84 mmHg; fixed effect model; p < 0.0001; and 1.87 mmHg; random effect model; p = 0.0055). The standardized mean difference between the treatments was 2.58 (fixed effect model; p < 0.0001) and 2.92 (random effect model; p = 0.0017) in favor of aliskiren. Compared with ramipril, aliskiren may have induced a more complete ‘upstream’ inhibition of the renin—angiotensin—aldosterone system, with consequent greater suppression of angiotensin II. Another potential explanation may be the longer terminal elimination halflife of aliskiren (about 40 hours) compared with ramiprilat (13—17 hours). These data provide further evidence that aliskiren monotherapy provides a sustained BP reduction over the 24 hours.
Current educational challenges for specialist community public health nurses following a health-visiting pathway and the consequences of these challenges for public health
Authors: Lindley P.J. , Sayer L. , Thurtle V.J.
Published: April 2010

The UK Standing Conference on Specialist Community Public Health Nurse Education represents the interests of those most intimately involved with specialist community public health nurse (health visitor) (SCPHN (HV)) education in higher education institutions across the UK. This paper summarizes issues currently affecting the education of SCPHN (HV)s and the delivery of health visiting and public health nursing services across the UK. Difficulties in recruitment, numbers of practice teachers and tensions created by the gap between expected and actual practice roles for health visitors are discussed. This discussion takes place in the context of the Programme of Action on Health Visiting, which was launched in 2009 by the Department of Health in England. Recommendations for action by HEIs are made in response to the difficulties identified in particular. Although this paper applies to all the UK SCPHN education programmes the majority of these are in England, which has resulted in a focus being placed on challenges in England.
Effects of pH, Ca- and SO4-concentration on surface charge and colloidal stability of goethite and hematite – consequences for the adsorption of anionic organic substances
Authors: Walsch J. , Dultz S.
Published: April 2010

Soil solution chemistry, especially pH and the presence of multivalent ions, affects the surface charge (SC) of Fe oxides and accordingly colloidal stability and sorption properties. The SC of synthetic goethite and hematite was quantified in the presence of different electrolytes (NaCl, CaCl2, Na2SO4and CaSO4) by combining the streaming potential with polyelectrolyte titration. The point of zero charge (PZC) for goethite was observed at pH 8.2 and the stability field around the PZC, where colloids are flocculated, is more extended (±1 pH unit) than that of hematite with a PZC at pH 7.1 (±0.5 pH unit). The SC decreases with increasing SO4concentration, indicating adsorption of SO4on the oxide, whereas the presence of Ca increases the SC. At pH 4, the addition of 0.1 mmol l–1Na2SO4induced a decrease in SC from 1.5 to 0.380 μmolcm–2for goethite and from 0.85 to 0.42 μmolcm–2for hematite. In a suspension with 0.1 mmol l–1Na2SO4, the number of colloids is already reduced, and both oxides flocculate rapidly and completely at >0.5 mmol l–1Na2SO4. While the addition of SO4did not affect charge titrations with the cationic polyelectrolyte, the anionic polyelectrolyte formed complexes with Ca, resulting in an overestimation of positive SC. The electrolyte CaSO4is most efficient at keeping goethite and hematite in the pH range 4–10 in the flocculated state. Besides pH, the presence of multivalent ions should also be considered when predicting colloid mediated transport and adsorption properties of anionic substances by Fe oxides in soil systems.
Modelling the process of kaolinite leaching from a copper mine flotation waste
Authors: Djurić I. , Mihajlović I. , Bogdanović D. , Živković Ž.
Published: April 2010

This paper presents the results of acidic leaching of kaolinite from the flotation waste of the RTB Bor copper mine, Serbia. The kaolinitic concentrate from the flotation waste contains 32% Al2O3. Kinetic investigations were conducted on the leaching of kaolinite roasted at 750°C for 60 min under air using H2SO4, HNO3 and HCl. Activation energies for the process were 74, 63 and 63.2 kJ mol–1 for sulphuric, nitric and hydrochloric acids, respectively. The kinetic function D3: [1 – (1 – α)1/3]2 = kt was chosen to describe the fractional conversion dependence on time and temperature. This enabled effective management of the leaching process to be carried out.
Use ofTmaxas a thermal maturity indicator in orogenic successions and comparison with clay mineral evolution
Authors: Dellisanti F. , Pini G. A. , Baudin F.
Published: April 2010

The relationship between three parameters, theTmaxgiven by Rock-Eval pyrolysis, the illite content in illite-smectite mixed layers (I-S) and the Ku¨bler Index (KI) has been investigated in the Cretaceous–Neogene, sedimentary syn-orogenic successions in the Northern Apennines (Italy). A strong relationship was found between maturity stages of kerogen, illite content in I-S and KI. The oil formation zone for continental organic matter (Type III), delimited byTmaxbetween 434 and 465ºC, corresponded to rocks with short-range ordering R1, I-S with illite content between 60 and 85% and KI values in the range 0.85–0.65 (ºΔ2θ). Over-mature rocks were characterized byTmax>465ºC, a long-range ordered I-S with an illite content >85% and KI in the range 0.65–0.45 (ºΔ2θ). The relationship permits use of both mineralogical parameters andTmaxto estimate palaeotemperatures in sedimentary successions and it can be exploited in hydrocarbon research to evaluate the petroleum potential.
Acid and aluminium modification of sepiolite and its application in FCC catalysis
Authors: Zheng Shu-Qin , Han Yong , Huang Xiao-Hong , Dai Ya-Li , Qian Dong , Zhang Jian-Ce , Ren Shao
Published: April 2010

The effects of acid and Al concentration, type of Al salt, treatment temperature and time of removal of Mg from sepiolite have been investigated, as has the use of modified sepiolite as an active fluid catalytic cracking (FCC) matrix. The samples were characterized by N2 adsorption and X-ray diffraction. Mg removal from sepiolite increased with increasing acid and Al ion concentration, treatment time and temperature. The temperature had the greatest impact on Mg removal. After acid and Al modification, 29% of the Mg was removed. When using the modified sepiolites as active matrices in FCC catalysts, the specific surface area, pore volume and mesoporous pore volume of the catalysts increased and they exhibited excellent performance in resisting the effects of heavy-metals as a result of the introduction of Mg oxide from the modified sepiolite.
Determination of soil aggregate disintegration dynamics using laser diffraction
Authors: Bieganowski A. , Ryżak M. , Witkowska-Walczak B.
Published: April 2010

A new practical and precise method for determining soil aggregate stability is described. Four air-dry aggregate fractions (<0.25, 0.25–0.5, 0.5–1.0 and 1.0–2.0 mm) were added to thoroughly stirred water in a Mastersizer 2000 laser diffractometer. The suspension obtained was passed directly through the measuring system. The dynamics of median (equivalent diameterd50) particle-size distribution decrease (interpolated with a logarithmic function) was assumed to be the measure of soil aggregate stability. In order to show the applicability of the new method, the results obtained (for selected and diverse soils) were compared with those from the wet sieving standard method. The main conclusion is that the proposed method is convenient and can be successfully used for the estimation of soil aggregate stability. Moreover, it has wider application because standard sieving methods are restricted to aggregates >0.25 mm whereas, with the use of the laser diffraction method, smaller aggregates can be measured. The energy delivered to the aggregates in the process of aggregate disintegration is more reproducible in the method described here. The method also provides an opportunity to verify that the soil aggregates are completely destroyed (lack of the changes of the median value shows the end of soil aggregate disintegration).
Palaeoenvironmental approach to the geology, mineralogy and geochemistry of an Early Miocene alluvial-fan to cyclic shallow-lacustrine depositional system in the Aktoprak Basin (central Anatolia), Turkey
Authors: Gürel A. , Kadir S.
Published: April 2010

The Aktoprak Basin, Turkey, provides important clues regarding regional palaeoclimatic changes which have not so far been elucidated. The purpose of the present study is to fill this gap using mineralogical, geochemical and isotopic characterization of cyclic sedimentation within Neogene sedimentary units. Early Miocene alluvial-fan to cyclic shallow-lacustrine sediments of the Aktoprak Basin consist of conglomerate, sandstone, mudstone, marl, limestone and palaeosol. The increasingly fine upward grain size and bed thicknesses suggest that the alluvial fan was fed by an ephemeral braided river. The cyclic sandflat–mudflat–shallow-lake succession is predominantly composed of small-scale sandstone-mudstone beds. Sandstone intervals in the sedimentary cycles are interpreted to be a result of sedimentation from shallow, ephemeral braided-river channels, the deposits having evolved under water-saturated conditions in response to climate changes. The mudstone intervals are interpreted as having been laid down via sedimentation during distal sheet floods which developed either under sub-aerial exposure or in a water-saturated environment. Palaeocurrent measurements indicate that the general transport direction in the Early Miocene was from east to west. The lacustrine sediments of the Aktoprak Basin consist of calcite + quartz + feldspar + serpentine coexisting mainly with smectite ± palygorskite ± illite ± chlorite. Illite and chlorite are either detrital, having originated from basement units, or the illite formed authigenically from smectite. Calcite and clay appear as cement-building conglomerate, sandstone and mudstone. The clay content decreases with increasing calcite and the presence of an inverse relationship between CaO and other oxides may correspond to an inverse relationship between calcite and other minerals. Furthermore, Al2O3, Fe2O3, TiO2, MgO, Ni, Co, Cu, Sr, Ba and Zr values in the smectite-bearing mudstone and sandstone are consistent with the chemical compositions of rocks in the surrounding area, mainly ophiolitic and volcanogenic associations. Micromorphologically, the development of smectite as a cement on leached feldspar, the occurrence of palygorskite fibres as bridges between crystals and rock fragments, as well as the presence of ‘edging’ smectite flakes suggest an authigenic origin. Field observations, mineralogy, geochemistry and the results of δ18O and δ13C isotopic determinations reveal that periodic palaeoclimatic changes were controlled by alternating wet and dry periods that resulted in a relative upward decrease in precipitation of authigenic smectite ± palygorskite within the sections, under the influence of geochemical and pH fluctuations in meteoric water within the shallow-lake environment.
Bentonite from Porto Santo Island, Madeira archipelago: surface properties studied by inverse gas chromatography
Authors: Cordeiro N. , Silva J. , Gomes C. , Rocha F.
Published: April 2010

The present paper shows the importance of Inverse Gas Chromatography (IGC) for the determination of the surface properties of bentonites. These properties are dispersive surface energy, acid-base properties, surface heterogeneity, sorption isotherms, BET surface areas and heat of sorption, using different probe molecules. IGC can contribute to the interpretation, prediction and optimization of the studied materials' properties. The paper focuses on two distinctive bentonite samples from Porto Santo Island, Madeira archipelago. In view of their potential value, achieved through their incorporation in products for dermopharmacy and dermocosmetics, particle size and particle surface properties are of fundamental importance.
Corrensite and chlorite-rich Chl-S mixed layers in sandstones from the ‘Macigno’ Formation (northwestern Tuscany, Italy)
Authors: Leoni L. , Lezzerini M. , Battaglia S. , Cavalcante F.
Published: April 2010

Corrensite and chlorite-rich chlorite-smectite (Chl-S) mixed-layers occurring in the Macigno Formation of northwestern Tuscany were investigated by XRPD/SEM techniques. The samples from the Macigno outcrops were affected by metamorphism corresponding to the high-diagenesis/low-anchizone transition boundary. The basal spacing of corrensite measured from 00lreflections on EG–Mg2+-saturated samples ranges from 30.97 to 31.18 Å with a coefficient of variation (CV) of 0.46–0.77%, consistent with the rational pattern of a 1:1 Chl-S periodic stacking sequence. X-ray patterns of heated K+-saturated specimens reveal the presence of two types of corrensite, probably with different interlayer charges on their respective smectite-like layers. The chlorite-rich Chl-S mixed layers coexisting with corrensite consist of R2 chlorite (0.70–0.75)/S and chlorite (0.90)/S with long-range orderingR⩾ 1. SEM observations show that corrensite and chlorite-rich Chl-S mixed-layers are closely mixed on a sub-micron scale. Some grains of corrensite and chlorite-rich Chl-S mixed-layers include zones (2–10 μm) of chlorite composition, as shown by microprobe analyses.
The structure of charoite, (K,Sr,Ba,Mn)15–16(Ca,Na)32[(Si70(O,OH)180)](OH,F)4.0.nH2O, solved by conventional and automated electron diffraction
Authors: Rozhdestvenskaya I. , Mugnaioli E. , Czank M. , Depmeier W. , Kolb U. , Reinholdt A. , Weirich T.
Published: April 2010

Charoite, ideally (K,Sr,Ba,Mn)15–16(Ca,Na)32[(Si70(O,OH)180)](OH,F)4.0·nH2O, a rare mineral from the Murun massif in Yakutiya, Russia, was studied using high-resolution transmission electron microscopy, selected-area electron diffraction, X-ray spectroscopy, precession electron diffraction and the newly developed technique of automated electron-diffraction tomography. The structure of charoite (a= 31.96(6) Å,b= 19.64(4) Å,c= 7.09(1) Å, β = 90.0(1)°,V= 4450(24) Å3, space groupP21/m) was solvedab initioby direct methods from 2878 unique observed reflections and refined toR1/wR2= 0.17/0.21. The structure can be visualized as being composed of three different dreier silicate chains: a double dreier chain, [Si6O17]10–; a tubular loop-branched dreier triple chain, [Si12O30]12–; and a tubular hybrid dreier quadruple chain, [Si17O43]18–. The silicate chains occur between ribbons of edge-sharing Ca and Na-octahedra. The chains of tetrahedra and the ribbons of octahedra extend parallel to thezaxis. K+, Ba2+, Sr2+, Mn2+and H2O molecules lie inside tubes and channels of the structure. On the basis of microprobe analyses and occupancy refinement of the cation sites, the crystal chemical formula of this charoite can be written as (Z= 1): (K13.88Sr1.0Ba0.32Mn0.36)Σ15.56(Ca25.64Na6.36)Σ32[(Si6O11(O,OH)6)2(Si12O18(O,OH)12)2(Si17O25(O,OH)18)2](OH,F)4.0·3.18H2O.