bluuebunny/crossref_metadata_2025 huggingface dataset:
Organelle dynamics and dysfunction: A closer link between peroxisomes and mitochondria
Authors: Camões F. , Bonekamp N. A. , Delille H. K. , Schrader M.
Published: December 2008

Mitochondria and peroxisomes are ubiquitous subcellular organelles, which fulfil an indispensable role in the cellular metabolism of higher eukaryotes. Moreover, they are highly dynamic and display large plasticity. There is growing evidence now that both organelles exhibit a closer interrelationship than previously appreciated. This connection includes metabolic cooperations and cross‐talk, a novel putative mitochondria‐to‐peroxisome vesicular trafficking pathway, as well as an overlap in key components of their fission machinery. Thus, peroxisomal alterations in metabolism, biogenesis, dynamics and proliferation can potentially influence mitochondrial functions, and vice versa. In this review, we present the latest progress in the emerging field of peroxisomal and mitochondrial interrelationship with a particular emphasis on organelle dynamics and its implication in diseases.
Developmental changes of oxalate excretion in enterally fed preterm infants
Authors: Illsinger S. , Lücke T. , Vaske B. , Schmidt K.‐H. , Bohnhorst B. , Das A. M.
Published: December 2008

To further substantiate gestational age‐related changes in oxalate excretion, we studied urinary oxalate excretion in 66 preterm infants born at 23.4–34.7 weeks of gestation. Spot urine of 66 preterm infants was analysed by ion chromatography as soon as they were completely orally fed with enriched breast milk and/or special preterm milk formula (days 7 to 57 of postnatal life). Infants with evidence of renal, gastrointestinal, muscular or metabolic disease were not included. Newborns on parenteral nutrition were excluded. Oxalate/creatinine ratios (Ox/Cr) decreased with gestational age (three age groups: group 1, 23 0/7–28 0/7; group 2, 28 1/7–32 0/7; and group 3, 32 1/7–35 0/7 weeks of gestation). The mean Ox/Cr was highest in group 1 (398.2 mmol/mol ± 116.8; n = 21). Differences between groups 1 + 3 were statistically significant; p = 0.001; those between groups 1 + 2 and between groups 2 + 3 were not. Ox/Cr correlated inversely with gestational and maturational age (r = −0.41, p = 0.001; r = −0.33, p = 0.007) and positively with postnatal age (r = 0.32, p = 0.008). It correlated inversely with birth weight as well as actual weight at sample collection (r = −0.46 and −0.44, p < 0.001). Ox/Cr was significantly linked to energy and carbohydrate intake (r = 0.3 and 0.4, p = 0.03 and 0.001). These results were independent of sex. In the present study we show that urinary oxalate excretion in preterm infants depends on gestational age.
Effect of pH on the Interaction of Gold Nanoparticles with DNA and Application in the Detection of Human p53 Gene Mutation
Authors: Sun Liping , Zhang Zhaowu , Wang Shuang , Zhang Jianfeng , Li Hui , Ren Lei , Weng Jian , Zhang Qiqing
Published: December 2008

Gold nanoparticles (GNPs) are widely used to detect DNA. We studied the effect of pH on the assembly/disassembly of single-stranded DNA functionalized GNPs. Based on the different binding affinities of DNA to GNPs, we present a simple and fast way that uses HCl to drive the assembly of GNPs for detection of DNA sequences with single nucleotide differences. The assembly is reversible and can be switched by changing the solution pH. No covalent modification of DNA or GNP surface is needed. Oligonucleotide derived from human p53 gene with one-base substitution can be distinguished by a color change of the GNPs solution or a significant difference of the maximum absorption wavelength (λmax), compared with wildtype sequences. This method enables detection of 10 picomole quantities of target DNA.
Studying the Influence of Alumina Catalysts Doped with Tin and Zinc Oxides in the Soybean Oil Pyrolysis Reaction
Authors: Quirino Rafael L. , Tavares André P. , Peres Antônio C. , Rubim Joel C. , Suarez Paulo A. Z.
Published: December 2008

The pyrolysis of vegetable oils consists of cracking triglycerides to produce smaller molecules. A mixture of hydrocarbons and oxygenated compounds, such as carboxylic acids and aldehydes, is obtained as the product and which can be separated by fractional distillation. When the reaction is carried out in the absence of catalysts (thermal cracking), a great quantity of these oxygenated compounds is obtained. Thus, the presence of those oxygenated compounds in the products results in a high level of acidity, which can be a problem when using them as fuels in combustion engines. The aim of this work was to study the composition of the products obtained by cracking of vegetable oils assisted by γ‐alumina doped with zinc and tin oxides. The products were analyzed by FT‐IR, GC‐MS and GC‐FID and the acid number was determined by titration with alcoholic KOH solution. The acid number, infrared spectra and chromatograms of the resulting hydrocarbon mixtures indicated a significant reduction in oxygenated compounds when compared with the mixtures obtained by the thermal cracking process, thus decreasing the acidity of the mixture.
How could host discrimination abilities influence the structure of a parasitoid community?
Authors: van Baaren J. , Le Lann C. , Pichenot J. , Pierre J.S. , Krespi L. , Outreman Y.
Published: December 2008

Three relatedAphidiusparasitoid species share the same host, the grain aphidSitobion avenae. Among this parasitoid community,Aphidius rhopalosiphiis the most abundant species in the field. Both the interspecific host discrimination ofA. rhopalosiphitowards hosts parasitized by the two other species (i.e.A. avenaeandA. ervi) and the interspecific host discrimination of the two other species towards hosts parasitized byA. rhopalosiphiwere studied here. Results showed that females ofA. rhopalosiphiandA. avenaeboth discriminated between unparasitized hosts and hosts parasitized by the other species. This discrimination occurred only after ovipositor insertion, suggesting the perception of an internal marker of parasitism. Likewise, females ofA. rhopalosiphiandA. erviwere able to discriminate between unparasitized hosts and hosts parasitized by the other species. However, in this combination of species, recognition of parasitized hosts occurred before ovipositor insertion, through an antennal perception, suggesting the presence an external cue indicating parasitism. Hence, interspecific host discrimination in the threeAphidiusspecies is based on internal or external cues, which are used either alone or together. Our results showed that the cues used for interspecific host discrimination depend on the specific identity of the interaction. These differences seemed strongly linked to the way the different species respond to defensive behaviours of their aphid hosts. Results are discussed in the context of optimal foraging and possible consequences for community structure.
The influence of late-stage pupal irradiation and increased irradiated: un-irradiated male ratio on mating competitiveness of the malaria mosquito Anopheles arabiensis Patton
Authors: Helinski M.E.H. , Knols B.G.J.
Published: December 2008

Competitiveness of released males in genetic control programmes is of critical importance. In this paper, we explored two scenarios to compensate for the loss of mating competitiveness after pupal stage irradiation in males of the malaria mosquito Anopheles arabiensis. First, competition experiments with a higher ratio of irradiated versus un-irradiated males were performed. Second, pupae were irradiated just prior to emergence and male mating competitiveness was determined.

Males were irradiated in the pupal stage with a partially or fully-sterilizing dose of 70 or 120 Gy, respectively. Pupae were irradiated aged 20–26 h (young) as routinely performed, or the pupal stage was artificially prolonged by cooling and pupae were irradiated aged 42–48 h (old). Irradiated males competed at a ratio of 3:1:1 to un-irradiated males for mates in a large cage design.

At the 3:1 ratio, the number of females inseminated by males irradiated with 70 Gy as young pupae was similar to the number inseminated by un-irradiated males for the majority of the replicates. At 120 Gy, significantly fewer females were inseminated by irradiated than by un-irradiated males. The irradiation of older pupae did not result in a significantly improved male mating competitiveness compared to the irradiation of young pupae.

Our findings indicate that the loss of competitiveness after pupal stage irradiation can be compensated for by a threefold increase of irradiated males, but only for the partially-sterilizing dose. In addition, cooling might be a useful tool to facilitate handling processes of large numbers of mosquitoes in genetic control programmes.
Strong cytoplasmic incompatibility and high vertical transmission rate can explain the high frequencies ofWolbachiainfection in Japanese populations ofColias erate poliographus(Lepidoptera: Pieridae)
Authors: Narita S. , Shimajiri Y. , Nomura M.
Published: December 2008

Wolbachia, belonging toAlphaproteobacteria, is ubiquitously found in arthropods and filarial nematodes, and is known to manipulate the reproduction of its hosts in various ways, such as feminization, male killing, induction of parthenogenesis or induction of cytoplasmic incompatibility. We found that theWolbachiainfection frequencies of the butterflyColias erate poliographuswere high (85.7–100%) in seven Japanese populations. Crossing experiments and rearing revealed that theWolbachiastrain exhibited strong cytoplasmic incompatibility and perfect vertical transmission inC. erate poliographus. Moreover, a comparison of the survival rates between infected and cured broods suggested thatWolbachiainfection had beneficial effects on host fitness. Our findings suggested that the high infection frequencies in Japanese populations have been accomplished by these advantageous traits of theWolbachiastrain. Furthermore, the multilocus sequence typing (MLST) scheme revealed that theWolbachiainC. erate poliographusis a novel strain (ST141), belonging to supergroup B.
Tessellation and Lyubich–Minsky laminations associated with quadratic maps, I: pinching semiconjugacies
Authors: KAWAHIRA TOMOKI
Published: December 2008

We constructtessellationsof the filled Julia sets of hyperbolic and parabolic quadratic maps. The dynamics inside the Julia sets are then organized by tiles which play the role of the external rays outside. We also construct continuous families of pinching semiconjugacies associated with hyperbolic-to-parabolic degenerationswithoutusing quasiconformal deformation. Instead, we achieve this via tessellation and investigation of the hyperbolic-to-parabolic degeneration of linearizing coordinates inside the Julia set.
Poisson suspensions and infinite ergodic theory
Authors: ROY EMMANUEL
Published: December 2008

We investigate the ergodic theory of Poisson suspensions. In the process, we establish close connections between finite and infinite measure-preserving ergodic theory. Poisson suspensions thus provide a new approach to infinite-measure ergodic theory. Fields investigated here are mixing properties, spectral theory, joinings. We also compare Poisson suspensions to the apparently similar looking Gaussian dynamical systems.
Global properties of a family of piecewise isometries
Authors: GOETZ AREK , QUAS ANTHONY
Published: December 2008

We investigate a basic system of a piecewise rotations acting on two half-planes. We prove that for invertible systems, an arbitrary neighbourhood of infinity contains infinitely many periodic points surrounded by periodic cells. In the case where the underlying rotation is rational, we show that all orbits remain bounded, whereas in the case where the underlying rotation is irrational, we show that the map is conservative (satisfies the Poincaré recurrence property). A key part of the proof is the construction of periodic orbits that shadow orbits for certain rational rotations of the plane.
Lambda-topology versus pointwise topology
Authors: ROY MARIO , SUMI HIROKI , URBAŃSKI MARIUSZ
Published: December 2008

This paper deals with families of conformal iterated function systems (CIFSs). The space CIFS(X,I) of all CIFSs, with common seed space X and alphabet I, is successively endowed with the topology of pointwise convergence and the so-calledλ-topology. We show just how bad the topology of pointwise convergence is: although the Hausdorff dimension function is continuous on a dense Gδ-set, it is also discontinuous on a dense subset of CIFS(X,I). Moreover, all of the different types of systems (irregular, critically regular, etc.), have empty interior, have the whole space as boundary, and thus are dense in CIFS(X,I), which goes against intuition and conception of a natural topology on CIFS(X,I). We then prove how good the λ-topology is: Roy and Urbański [Regularity properties of Hausdorff dimension in infinite conformal IFSs. Ergod. Th. & Dynam. Sys.25(6) (2005), 1961–1983] have previously pointed out that the Hausdorff dimension function is then continuous everywhere on CIFS(X,I). We go further in this paper. We show that (almost) all of the different types of systems have natural topological properties. We also show that, despite not being metrizable (as it does not satisfy the first axiom of countability), the λ-topology makes the space CIFS(X,I) normal. Moreover, this space has no isolated points. We further prove that the conformal Gibbs measures and invariant Gibbs measures depend continuously on Φ∈CIFS(X,I) and on the parameter t of the potential and pressure functions. However, we demonstrate that the coding map and the closure of the limit set are discontinuous on an important subset of CIFS(X,I).
A family of entire functions with Baker domains
Authors: FLEISCHMANN DOMINIQUE S.
Published: December 2008

In his paper [The iteration of polynomials and transcendental entire functions. J. Aust. Math. Soc. (Series A)30 (1981), 483–495], Baker proved that the function f defined by has a Baker domain for c sufficiently large. In this paper we use a novel method to prove that f has a Baker domain for all c>0. We also prove that there exists an open unbounded set contained in the Baker domain on which the orbits of points under f are asymptotically horizontal.
Augmented dimension groups and ordered cohomology
Authors: BARGE MARCY , SMITH MEGAN
Published: December 2008

We show that the ordered MatsumotoK0-group of a substitutive system is derivable from the ordered Čech cohomology of a simple ‘augmentation’ of the tiling space associated with the substitution. Besides supplying a topological interpretation of the MatsumotoK0-group, this leads to finer invariants of the flow equivalence class of a substitutive system.
The KAM theorem and renormalization group
Authors: DE SIMONE E. , KUPIAINEN A.
Published: December 2008

We give an elementary proof of the analytic KAM theorem by reducing it to a Picard iteration of a certain PDE with quadratic nonlinearity, the so-called Polchinski renormalization group equation studied in quantum field theory.
A classification of explosions in dimension one
Authors: SANDER E. , YORKE J. A.
Published: December 2008

A discontinuous change in the size of an attractor is the most easily observed type of global bifurcation. More generally, anexplosionis a discontinuous change in the set of recurrent points. An explosion often results from heteroclinic and homoclinic tangency bifurcations. We prove that, for one-dimensional maps, explosions are generically the result of either tangency or saddle-node bifurcations. Furthermore, we give necessary and sufficient conditions for generic tangency bifurcations to lead to explosions.
Databases for assessing the outcomes of the treatment of patients with congenital and paediatric cardiac disease – the perspective of cardiac surgery
Authors: Jacobs Marshall Lewis , Jacobs Jeffrey Phillip , Franklin Rodney C.G. , Mavroudis Constantine , Lacour-Gayet Francois , Tchervenkov Christo I. , Walters Hal , Bacha Emile A. , Clarke David Robinson , William Gaynor J. , Spray Thomas L. , Stellin Giovanni , Ebels Tjark , Maruszewski Bohdan , Tobota Zdzislaw , Kurosawa Hiromi , Elliott Martin
Published: December 2008

This review includes a brief discussion, from the perspective of cardiac surgeons, of the rationale for creation and maintenance of multi-institutional databases of outcomes of congenital heart surgery, together with a history of the evolution of such databases, a description of the current state of the art, and a discussion of areas for improvement and future expansion of the concept. Five fundamental areas are reviewed: nomenclature, mechanism of data collection and storage, mechanisms for the evaluation and comparison of the complexity of operations and stratification of risk, mechanisms to ensure the completeness and accuracy of the data, and mechanisms for expansion of the current capabilities of databases to include comparison and sharing of data between medical subspecialties. This review briefly describes several European and North American initiatives related to databases for pediatric and congenital cardiac surgery the Congenital Database of The European Association for Cardio-Thoracic Surgery, the Congenital Database of The Society of Thoracic Surgeons, the Pediatric Cardiac Care Consortium, and the Central Cardiac Audit Database in the United Kingdom. Potential means of approaching the ultimate goal of acquisition of long-term follow-up data, and input of this data over the life of the patient, are also considered.
Databases for assessing the outcomes of the treatment of patients with congenital and paediatric cardiac disease – the perspective of cardiology
Authors: Jenkins Kathy J. , Beekman III Robert H. , Bergersen Lisa J. , Everett Allen D. , Forbes Thomas J. , Franklin Rodney C. G. , Klitzner Thomas S. , Krogman Otto N. , Martin Gerard R. , Webb Catherine L.
Published: December 2008

This review includes a brief discussion, from the perspective of the pediatric cardiologist, of the rationale for creation and maintenance of multi-institutional databases of outcomes of the treatment of patients with congenital and paediatric cardiac disease, together with a history of the evolution of such databases, and a description of the current state of the art. A number of projects designed to have broad-based impact are currently in the design phase, or have already been implemented. Not surprisingly, most of the efforts thus far have focused on catheterization procedures and interventions, although some work examining other aspects of paediatric cardiology practice is also beginning. This review briefly describes several European and North American initiatives related to databases for pediatric and congenital cardiology including the Central Cardiac Audit Database of the United Kingdom, national database initiatives for pediatric cardiology in Switzerland and Germany, various database initiatives under the leadership of the Working Groups of The Association for European Paediatric Cardiology, the IMPACT Registry™ (IMproving Pediatric and Adult Congenital Treatment) of the National Cardiovascular Data Registry® of The American College of Cardiology Foundation® and The Society for Cardiovascular Angiography and Interventions (SCAI), the Mid-Atlantic Group of Interventional Cardiology (MAGIC) Catheterization Outcomes Project, the Congenital Cardiac Catheterization Project on Outcomes (C3PO), the Congenital Cardiovascular Interventional Study Consortium (CCISC), and the Joint Council on Congenital Heart Disease (JCCHD) National Quality Improvement Initiative. These projects, each leveraging multicentre data and collaboration, demonstrate the enormous progress that has occurred over the last several years to improve the quality and consistency of information about nonsurgical treatment for congenital cardiac disease. The paediatric cardiology field is well-poised to move quickly beyond outcome assessment and benchmarking, to collaborative quality improvement.
Databases for assessing the outcomes of the treatment of patients with congenital and paediatric cardiac disease – the perspective of anaesthesia
Authors: Vener David F. , Jacobs Jeffrey P. , Schindler Ehrenfried , Maruszewski Bohdan , Andropoulos Dean
Published: December 2008

The Congenital Cardiac Anesthesia Society was formed in 2005 by representatives from many of the busiest congenital cardiac surgical programs in North America and is now in the process of partnering with The Society of Thoracic Surgeons to create a joint congenital cardiac surgery and congenital cardiac anaesthesia database. Even the busiest of congenital cardiac programs have a low frequency of anaesthesia-related cardiac complications and deaths. One of the only mechanisms for accurately determining the incidence and outcomes of low frequency events is to aggregate large amounts of data from multiple sources. To that end, the Congenital Cardiac Anesthesia Society has joined with the Society of Thoracic Surgeons Congenital Database Task Force to incorporate anaesthesia-specific data points into their surgical registry, which is now the largest single reporting site for children and adults undergoing surgical repair of congenital cardiac malformations in North America. The Joint Congenital Cardiac Anesthesia Society – Society of Thoracic Surgeons Database will therefore become an optional module of The Society of Thoracic Surgeons Congenital Heart Surgery Database. Initial data fields have been selected and are presented in this article.

Efforts are ongoing to make this initiative a global project. Initial collaborative discussions have taken place about the possibility of linking this initiative with the European Association of Cardiothoracic Anesthesiologists. It is certainly possible and desirable that the planned anaesthesia module of The Society of Thoracic Surgeons Congenital Heart Database has an identical module in the congenital heart database of The European Association for Cardio-Thoracic Surgery and The European Congenital Heart Surgeons Association. This project should also ideally spread beyond North America and Europe. Efforts to involve Africa, Asia, Australia, and South America are necessary and already underway. The creation of a joint cardiac surgery and anaesthesia database is another step towards the ultimate goal of creating a database for congenital heart disease that spans both geographical and subspecialty boundaries.
Arrhythmic complications associated with the treatment of patients with congenital cardiac disease: consensus definitions from the Multi-Societal Database Committee for Pediatric and Congenital Heart Disease
Authors: Deal Barbara J. , Mavroudis Constantine , Jacobs Jeffrey Phillip , Gevitz Melanie , Backer Carl Lewis
Published: December 2008

A detailed hierarchal nomenclature of arrhythmias is offered with definition of its applications to diagnosis and complications. The conceptual and organizational approach to discussion of arrhythmias employs the following sequence: location – mechanism – aetiology – duration. The classification of arrhythmias is heuristically divided into an anatomical hierarchy: atrial, junctional, ventricular, or atrioventricular. Mechanisms are most simplistically classified as either reentrant, such as macro-reentrant atrial tachycardia, previously described as atrial flutter, or focal, such as automatic or micro-reentrant tachycardia, for example, junctional ectopic tachycardia. The aetiology of arrhythmias can be either iatrogenic, such as postsurgical, or non-iatrogenic, such as genetic or congenital, and in many cases is multi-factorial. Assigning an aetiology to an arrhythmia is distinct from understanding the mechanism of the arrhythmia, yet assignment of a possible aetiology of an arrhythmia may have important therapeutic implications in certain clinical settings. For example, postoperative atrial arrhythmias in patients after cardiac transplantation may be harbingers of rejection or consequent to remediable imbalances of electrolytes. The duration, frequency of, and time to occurrence of arrhythmia are temporal measures that further refine arrhythmia definition, and may offer insight into ascription of aetiology. Finally, arrhythmias do not occur in a void, but interact with other organ systems. Arrhythmias not only can result from perturbations of other organ systems, such as renal failure, but can produce dysfunction in other organ systems due to haemodynamic compromise or embolic phenomena.
Haematological and infectious complications associated with the treatment of patients with congenital cardiac disease: consensus definitions from the Multi-Societal Database Committee for Pediatric and Congenital Heart Disease
Authors: Checchia Paul A. , Karamlou Tara , Maruszewski Bohdan , Ohye Richard G. , Bronicki Ronald , Dodge-Khatami Ali
Published: December 2008

A complication is an event or occurrence that is associated with a disease or a healthcare intervention, is a departure from the desired course of events, and may cause, or be associated with, suboptimal outcome. A complication does not necessarily represent a breech in the standard of care that constitutes medical negligence or medical malpractice. An operative or procedural complication is any complication, regardless of cause, occurring (1) within 30 days after surgery or intervention in or out of the hospital, or (2) after 30 days during the same hospitalization subsequent to the operation or intervention. Operative and procedural complications include both intraoperative/intraprocedural complications and postoperative/postprocedural complications in this time interval.

The MultiSocietal Database Committee for Pediatric and Congenital Heart Disease has set forth a comprehensive list of complications associated with the treatment of patients with congenital cardiac disease, related to cardiac, pulmonary, renal, haematological, infectious, neurological, gastrointestinal, and endocrinal systems, as well as those related to the management of anaesthesia and perfusion, and the transplantation of thoracic organs. The objective of this manuscript is to examine the definitions of operative morbidity as they relate specifically to the haematological system and to infectious complications. These specific definitions and terms will be used to track morbidity associated with surgical and transcatheter interventions and other forms of therapy in a common language across many separate databases.

The MultiSocietal Database Committee for Pediatric and Congenital Heart Disease has prepared and defined a near-exhaustive list of haematological and infectious complications. Within each subgroup, complications are presented in alphabetical order. Clinicians caring for patients with congenital cardiac disease will be able to use this list for databases, quality improvement initiatives, reporting of complications, and comparing strategies for treatment.
A Notice
Authors: MacDonald M. C. A.
Published: December 2008

After Burckhardt's ‘rediscovery’ of Petra in 1812, no other Europeans were able to visit the site until William John Bankes led an expedition in 1818. Unlike Burckhardt, Bankes and his companions were granted two days in which they could freely explore and record as much as possible. They used the time to the full, and with great energy and skill produced an astonishingly large collection of information.
Determinants of undernutrition in rural communities of a protected area in Gabon
Authors: Blaney S , Beaudry M , Latham M
Published: December 2008

Objective

To understand how access to natural resources may contribute to nutrition.

Design

In each of the two major seasons, data were collected during a 7 d period using observations, semi-structured interviews, anthropometric measures and a weighed food consumption survey.

Setting

Four rural communities selected to represent inland and coastal areas of the Gamba Complex in Gabon.

Subjects

In each community, all individuals from groups vulnerable to malnutrition, i.e. children aged 0–23 months (n 41) and 24–59 months (n 63) and the elderly (n 101), as well as women caregivers (n 96).

Results

In most groups, household access to natural resources was associated with household access to food but not with individual nutritional status. In children aged 0–23 months, access to care and to health services and a healthy environment were the best predictors of length-for-age (adjusted R2: 14 %). Health status was the only predictor of weight-for-height in children aged 24–59 months (adjusted R2: 14 %). In women caregivers, household food security was negatively associated with nutritional status, as was being younger than 20 years (adjusted R2: 16 %). Among the elderly, only nutrient adequacy predicted nutritional status (adjusted R2: 5 %).

Conclusion

Improving access to care and health for young children would help reverse the process of undernutrition. Reaching a better understanding of how the access of individuals to both food and other resources relate to household access could further our appreciation of the constraints to good nutrition. This is particularly relevant in women to ensure that their possibly important contribution to the household is not at their own expense.
Stehen kognitive Funktionen im Zusammenhang mit Angst, Depression und Posttraumatischer Belastungsstörung bei Brustkrebspatientinnen nach onkologischer Behandlung?
Authors: Schirmer Lena , Mehnert Anja , Scherwath Angela , Schleimer Barbara , Schulz-Kindermann Frank , Zander Axel R. , Koch Uwe
Published: December 2008

Die in mehreren Studien gefundenen kognitiven Störungen bei Tumorpatienten nach Chemotherapie werden zumeist mit der Zytostatikaneurotoxizität assoziiert. In der vorliegenden Arbeit wird der Zusammenhang von Angst, Depression und Posttraumatischer Belastungsstörung mit der kognitiven Leistungsfähigkeit bei Frauen mit Mammakarzinom untersucht. Insgesamt wurden 76 Brustkrebspatientinnen fünf Jahre nach Abschluss der onkologischen Behandlung mit neuropsychologischen Testverfahren sowie mit der Hospital Anxiety and Depression Scale – Deutsche Version (HADS-D) und der Posttraumatic Stress Disorder Checklist – Civilian Version (PCL-C) untersucht: 23 nach Standard- und 24 nach Hochdosistherapie sowie 29 nach Brustoperation und Strahlentherapie als Vergleichsgruppe. Signifikante Zusammenhänge sind vor allem zwischen kognitiven Funktionen und Intrusionssymptomen einer Posttraumatischen Belastungsstörung (PTBS) festzustellen. Bei Patientinnen nach Standardtherapie weisen Intrusionen der PTBS einen moderaten Zusammenhang mit der globalen kognitiven Beeinträchtigung auf. Die Ergebnisse der Studie deuten auf multidimensionale Einfluss- und moderierende Faktoren bei der Entwicklung kognitiver Defizite bei Brustkrebspatientinnen nach onkologischer Therapie hin.
Avalanche crown‐depth distributions
Authors: Bair Edward H. , Dozier Jeff , Birkeland Karl W.
Published: December 2008

The literature disagrees about the statistical distribution of snow avalanche crown depths. Large datasets from Mammoth Mountain, California and the Westwide Avalanche Network show that the three‐parameter generalized extreme value distribution provides the most robust fit, followed by a two‐parameter variation, the Fréchet distribution. The most parsimonious explanation is neither self‐organized criticality nor other complex cascades, but the maximum domain of attraction, implying that distributions of individual avalanche crown depths are scaling. We also show that crown depths do not have a universal tail index. Rather, they range from 2.8 to 4.6 over different avalanche paths, consistent with other geophysical phenomena such as wildfires, which show similar variability.
Evidence and theory for trapped electrons in guide field magnetotail reconnection
Authors: Egedal J. , Fox W. , Katz N. , Porkolab M. , Øieroset M. , Lin R. P. , Daughton W. , Drake J. F.
Published: December 2008

A previous analysis of electron distributions measured in situ by the Wind spacecraft has revealed that electrons were trapped in the electromagnetic geometry of the reconnection event encountered in the deep magnetotail. In this paper we develop a detailed theory that can account for the main anisotropic features of the electron distributions associated with trapping in reconnection. The analysis shows that electron trapping in electric fields is generic in reconnection, as it is required in order to maintain the condition of quasineutrality. In addition to the spacecraft data, evidence of trapping in numerical simulations is also presented. Trapping is effective in eliminating free‐streaming electrons along magnetic fields and thereby reduces parallel electron currents. Its importance for fast reconnection is discussed and emphasized by observations in a laboratory plasma.
CloudSat mission: Performance and early science after the first year of operation
Authors: Stephens Graeme L. , Vane Deborah G. , Tanelli Simone , Im Eastwood , Durden Stephen , Rokey Mark , Reinke Don , Partain Philip , Mace Gerald G. , Austin Richard , L'Ecuyer Tristan , Haynes John , Lebsock Matthew , Suzuki Kentaroh , Waliser Duane , Wu Dong , Kay Jen , Gettelman Andrew , Wang Zhien , Marchand Rojer
Published: December 2008

This paper reports on the early mission performance of the radar and other major aspects of the CloudSat mission. The Cloudsat cloud profiling radar (CPR) has been operating since 2 June 2006 and has proven to be remarkably stable since turn‐on. A number of products have been developed using these space‐borne radar data as principal inputs. Combined with other A‐Train sensor data, these new observations offer unique, global views of the vertical structure of clouds and precipitation jointly. Approximately 11% of clouds detected over the global oceans produce precipitation that, in all likelihood, reaches the surface. Warm precipitating clouds are both wetter and composed of larger particles than nonprecipitating clouds. The frequency of precipitation increases significantly with increasing cloud depth, and the increased depth and water path of precipitating clouds leads to increased optical depths and substantially more sunlight reflected from precipitating clouds compared to than nonprecipitating warm clouds. The CloudSat observations also provide an authoritative estimate of global ice water paths. The observed ice water paths are larger than those predicted from most climate models. CloudSat observations also indicate that clouds radiatively heat the global mean atmospheric column (relative to clear skies) by about 10 Wm−2. Although this heating appears to be contributed almost equally by solar and infrared absorption, the latter contribution is shown to vary significantly with latitude being influenced by the predominant cloud structures of the different region in questions.
Venus surface thermal emission at 1 μm in VIRTIS imaging observations: Evidence for variation of crust and mantle differentiation conditions
Authors: Mueller N. , Helbert J. , Hashimoto G. L. , Tsang C. C. C. , Erard S. , Piccioni G. , Drossart P.
Published: December 2008

The Venus Express spacecraft images the nightside thermal emissions using the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS). At 1.02, 1.10, and 1.18 μm, thermal emission from the surface is observed. The signal is attenuated by scattering and absorption in the dense atmosphere. The measured flux at the top of the atmosphere is positively correlated with surface temperature and surface emissivity. The surface temperature of Venus is relatively well constrained as being mainly a function of altitude with a gradient lesser or equal to the adiabatic lapse rate. This study examines the correlation of VIRTIS images showing a signal of the surface at 1.02 μm with viewing geometry, stray sunlight, cloud opacity, and topography and applies semiempirical relations to remove their influence. The remaining contrast can be either ascribed to surface emissivity or unexpected temperature variations. Temperature variations due to active volcanism are unlikely to be persistent over the time of observations; therefore, the mosaic of all processed images is here interpreted in terms of surface emissivity variation. The emissivity variation found is correlated with geomorphological features established from Magellan synthetic aperture radar images. It is generally lower at tessera terrain. Some, but not all, volcanic edifices show increased emissivity. Large lava flows in the Lada terra‐Lavinia planitia region also show an increased thermal emission. This might indicate a more felsic surface composition of tessera highlands and large‐scale extrusive volcanism of ultramafic composition.
Influence of Text Type, Topic Familiarity, and Stuttering Frequency on Listener Recall, Comprehension, and Mental Effort
Authors: Panico James , Healey E. Charles
Published: December 2008

Purpose

To determine how text type, topic familiarity, and stuttering frequency influence listener recall, comprehension, and perceived mental effort.

Method

Sixty adults listened to familiar and unfamiliar narrative and expository texts produced with 0%, 5%, 10%, and 15% stuttering. Participants listened to 4 experimental text samples at only 1 stuttering frequency. After hearing the text samples, each listener performed a free recall task, answered cued recall questions, answered story comprehension questions, and rated their perceived mental effort.

Results

Free and cued recall as well as story comprehension scores were higher for narrative than for expository texts. Free and cued recall scores were better for familiar than for unfamiliar stories, although topic familiarity did not affect story comprehension scores. Samples with all levels of stuttering resulted in higher mental effort ratings for both text types and topic familiarities.

Conclusions

Stuttering has a greater influence on listener recall and comprehension for narrative than for expository texts. Topic familiarity affects free and cued recall but has no influence on story comprehension. Regardless of the amount of stuttering, mental effort was high for both text types and levels of familiarity.
Electron inelastic scattering and secondary electron emission calculated without the single pole approximation
Authors: Mao S. F. , Li Y. G. , Zeng R. G. , Ding Z. J.
Published: December 2008

In this work, aimed primarily at providing more accurate electron inelastic mean free paths (IMFPs) and stopping powers (SPs) at low energies than are provided by the single pole approximation, the “full Penn” algorithm has been employed to derive the electron inelastic scattering energy loss function in solids. IMFPs and SPs have thus been calculated in the energy range from 1 eV to 10 keV and are in good agreement with the experimental data. This treatment of electron inelastic scattering combined with a consistent model for the cascade secondary electron generation has enabled more elaborate Monte Carlo simulations of secondary electron emission from metals. The calculated results of the energy distributions and the secondary electron emission yields for Al and Cu agree reasonably with experimental results.
Cloning from stem cells: different lineages, different species, same story
Authors: Oback Björn
Published: December 2008

Following nuclear transfer (NT), the most stringent measure of extensive donor cell reprogramming is development into viable offspring. This is referred to as cloning efficiency and quantified as the proportion of cloned embryos transferred into surrogate mothers that survive into adulthood. Cloning efficiency depends on the ability of the enucleated recipient cell to carry out the reprogramming reactions (‘reprogramming ability’) and the ability of the nuclear donor cell to be reprogrammed (‘reprogrammability’). It has been postulated that reprogrammability of the somatic donor cell epigenome is inversely proportional to its differentiation status. In order to test this hypothesis, reprogrammability was compared between undifferentiated stem cells and their differentiated isogenic progeny. In the mouse, cells of divergent differentiation status from the neuronal, haematopoietic and skin epithelial lineage were tested. In cattle and deer, skeletal muscle and antler cells, respectively, were used as donors. No conclusive correlation between differentiation status and cloning efficiency was found, indicating that somatic donor cell type may not be the limiting factor for cloning success. This may reflect technical limitations of the NT-induced reprogramming assay. Alternatively, differentiation status and reprogrammability may be unrelated, making all cells equally difficult to reprogramme once they have left the ground state of pluripotency.
Cryopreservation of manipulated embryos: tackling the double jeopardy
Authors: Dinnyes A. , Nedambale T. L.
Published: December 2008

The aim of the present review is to provide information to researchers and practitioners concerning the reasons for the altered viability and the medium- and long-term consequences of cryopreservation of manipulated mammalian embryos. Embryo manipulation is defined herein as the act or process of manipulating mammalian embryos, including superovulation, AI, IVM, IVF, in vitro culture, intracytoplasmic sperm injection, embryo biopsy or splitting, somatic cell nuclear transfer cloning, the production of sexed embryos (by sperm sexing), embryo cryopreservation, embryo transfer or the creation of genetically modified (transgenic) embryos. With advances in manipulation technologies, the application of embryo manipulation will become more frequent; the proper prevention and management of the resulting alterations will be crucial in establishing an economically viable animal breeding technology.
101 EFFECT OF DIETARY UREA ON EMBRYONIC VIABILITY AND DEVELOPMENT OF TOGGENBURG GOATS
Authors: Amorim L. S. , Torres C. A. A. , Amorim E. A. M. , Guimarães J. D. , Fonseca J. F. , Siqueira L. G. B. , Seidel G. E.
Published: December 2008

Urea supplementation in the diet of ruminants may alter the pH and protein concentration in different tissues and may affect the embryo quality and viability. Imbalances in nitrogen metabolism during the periods of oocyte growth and/or fertilization may dispose the zygote, pre-implantation embryo, and surviving conceptus to developmental errors. The aim of this research was to investigate the effect of feeding urea to goats on embryo quality. Eighteen Toggenburg goats, 48.6 ± 7.9 kg of BW, 2.9 ± 0.5 BCS, and 34.3 ± 20.8 months of age, were allocated randomly to 2 treatments: T1 (control, n = 8): no urea, and T2 (n = 10): 2.4% of dry matter (DM) as urea in the diet. The animals were fed diets based on Coast-cross hay (Cynodon dactylon) and concentrate (14% crude protein, DM basis) for 42 ± 2 days before embryo flushing. Estrus was synchronized with intravaginal sponges impregnated with 60 mg of medroxyprogesterone acetate (Progespon®, Syntex S.A., Buenos Aires, Argentina) for 11 days plus i.m. injection of 100 μg of cloprostenol (Ciosin®, Schering-Plough, Cotia, Brazil), on the Day 9. The superovulation protocol consisted of i.m. injections of 200 mg equivalent of NIH-FSH-P-1 (Folltropin®, Bioniche, Athens, GA), in 6 decreasing doses at 12-h intervals, on Days 9, 10, and 11 (Day 0 = sponge insertion). Estrus was monitored twice a day for 30 min from sponge withdrawal by use of teaser bucks, and females were mated by fertile bucks every 12 h during standing estrus. Early luteal regression was preventing by administration of an antiluteolytic (Banamine®, Schering-Plough) 72 h after sponge withdrawal, 1.1 mg kg–1 per day i.m. for 3 days. Embryo recovery was done on the seventh day of estrous cycle by a transcervical technique. Recovered embryos were classified by quality (I = excellent, V = degenerated), development stage percent (1 = unfertilized oocytes, 9 = hatched blastocyst), and viability with the embryo grades 1 (excellent), 2 (good), and 3 (fair). The effect of urea supplementation on embryo stage and viability was analyzed by ANOVA. From the 18 goats, 12 (67%) were responsive to the superovulation protocol, 62.5% from T1 and 70.0% from T2. The number of embryos flushed (7.20 ± 2.39 v. 6.29 ± 2.93) and the percentage and number of viable embryos [100% (36/36) v. 100% (39/39)] from T1 and T2 were not different (P > 0.01). Thereafter, embryos in advanced stages of development (7, 8, and 9) were 58.65% from T2 compared with 0% from T1 (P < 0.01). In addition to the embryos, 13 unfertilized oocytes were recovered from the T2 goats v. none from the T1 goats (P < 0.01). These results suggest that urea may cause acceleration of embryo development and may affect oocyte fertilization.

Supported by grants from CNPq, FAPEMIG, CAPES, Schering Plough®, Tecnopec®, and Carbogel®.
106 ANGIOGENIC FACTOR mRNA EXPRESSION IN FETAL MEMBRANES IN EARLY PREGNANT SHEEP
Authors: Johnson M. L. , Reynolds L. P. , Minten M. A. , Borowicz P. P. , Redmer D. A. , Grazul-Bilska A. T.
Published: December 2008

Maternal and fetal placental development may be compromised by use of assisted reproductive techniques, including cloning, resulting in poor placental angiogenesis and subsequent high embryonic/fetal loss (Palmieri et al. 2007 Placenta 28, 577–584). Before changes in vascular development in placenta from compromised pregnancies can be understood, a detailed knowledge of regulation of angiogenesis in placental tissues from normal pregnancies is necessary. Therefore, this study determined the expression pattern of mRNA for several angiogenic factors and their receptors: vascular endothelial growth factor (VEGF) and receptor (R) 1 and 2; basic fibroblast growth factor (FGF2) and FGFRIIIc; angiopoietin (ANGPT) 1 and 2 and ANGPTR (Tie2); endothelial nitric oxide synthase (eNOS) and NO receptor GUCY1B3 in fetal membranes (FM; fetal placenta) collected on Days 16, 18, 20, 22, 24, 26, 28, and 30 after mating (n = 5 to 8/day). Fetal membranes were snap frozen for evaluation of gene expression using quantitative, real-time RT-PCR. VEGF mRNA was increased (P < 0.05) 2-fold on Days 28 and 30 compared with Days 16, 18, and 20, whereas VEGFR1 mRNA increased (P < 0.05) 25- to 50-fold on Days 28 and 30 compared with Day 16, and VEGFR2 mRNA was greatest (P < 0.05) on Day 22 compared with Days 16, 18, 28, and 30. FGF2 mRNA was 4-fold greater (P < 0.05) on Day 22 compared with Day 16; however, FGF2RIIIc was unchanged from Day 16 through 30. eNOS mRNA was greatest (P < 0.05) on Days 22 and 24 compared with Days 16 and 18, but GUCY1B3 mRNA was greatest (P < 0.05) on Day 18 compared with Days 20, 24, and 28. ANGPT1 mRNA increased (P < 0.05) 40-fold by Days 28 and 30 compared with Days 16 and 18. ANGPT2 mRNA was undetectable on Day 16, and increased (P < 0.05) 5-fold from Days 18 through 30. ANGPTR mRNA was greatest (P < 0.05) on Days 22 and 24 compared with Days 16 and 18. This description of expression of factors potentially regulating early placental angiogenesis during normal pregnancy in sheep will provide the foundation for understanding the dramatic increases in capillary cell proliferation and capillary size we have previously observed (unpublished) and for determining whether placental vascular development is altered in compromised pregnancies.

USDA-NRI grant 2007-01215 to LPR and ATGB; NIH grant HL64141 to LPR and DAR; ND EPSCoR AURA grant to ATGB and MAM; ND Space Grant Fellowship Program award to MAM; and NIH grant P20 RR016741 (INBRE program of the NCRR, NIH).