bluuebunny/crossref_metadata_2025 huggingface dataset:
The Mark–Houwink–Sakurada Equation for the Viscosity of Atactic Polystyrene
Authors: Wagner Herman L.
Published: February 2011

In this review, the second in a series, the viscosity–molecular weight (Mark–Houwink–Sakurada) relationships have been critically evaluated for atactic polystyrene for a variety of solvents often used for viscosity measurements. These are benzene, toluene, 1,2,4-trichlorobenzene, tetrahydrofuran, o-dichlorobenzene, 2-butanone, and two theta solvents, cyclohexane and decalin. In addition, the Mark–Houwink–Sakurada parameters for several other solvents, not used as frequently, are provided.
Standard Chemical Thermodynamic Properties of Alkylcyclopentane Isomer Groups, Alkylcyclohexane Isomer Groups, and Combined Isomer Groups
Authors: Alberty Robert A. , Ha Young S.
Published: February 2011

The standard chemical thermodynamic properties of the alkylcyclopentane isomer groups have been calculated through C9H18 in the ideal gas phase from 298.15 to 1000 K, and the properties of the alkylcyclohexane isomer groups have been calculated through C10H20. The properties of individual species for which literature data are not available have been estimated using the Benson method. The increments per carbon atom in the isomer group properties have been calculated to determine the extent to which extrapolations may be made to higher carbon numbers. Since alkylcyclopentanes and alkylcyclohexanes of the same carbon number are isomers, the chemical thermodynamic properties of these combined isomer groups have also been calculated. Values of C○P, S○, ΔfH○, and ΔfG○ are given for the individual cyclopentane species through C9H18 and for the individual cyclohexane species through C10H20 for a standard state pressure of 1 bar.
Characterisation and genetic diversity analysis of selected chickpea cultivars of nine countries using simple sequence repeat (SSR) markers
Authors: Sefera Tadesse , Abebie Bekele , Gaur Pooran M. , Assefa Kebebew , Varshney Rajeev K.
Published: February 2011

The genomic DNA profiles of 48 chickpea cultivars released in nine countries and of historical significance to the chickpea breeding programs at ICRISAT and in Ethiopia were evaluated using 48 simple sequence repeat (SSR) markers. Across the cultivars, a total of 504 alleles representing the 48 SSR loci were detected with frequencies ranging from three to 22 (mean 10.5) alleles per locus. The polymorphism information content (PIC) for the SSR markers varied from 0.37 to 0.91 (mean 0.77). A subset of only three highly informative SSR markers (TA176, TA2, TA180) enabled complete discrimination among all 48 chickpea cultivars tested. Hierarchical neighbour-joining UPGMA cluster analysis based on simple matching dissimilarity matrix resolved the 48 cultivars into two major clusters representing desi and kabuli types. These cluster groupings of the cultivars were consistent with the pedigree information available for the cultivars as to the phenotypic classes of chickpea types. Analysis of the temporal patterns of the SSR diversity by classifying 48 chickpea cultivars into four periods of release revealed increasing tendencies in the overall genetic diversity from 0.42 for the earliest varieties developed in the 1970s to 0.62 for those released in the 1980s, and reached a maximum and equivalent level of 0.72 for the varieties developed in the 1990s and 2000s. Overall, the study ascertained that SSRs provide powerful marker tools in revealing genetic diversity and relationships in chickpeas, thereby proving useful for selection of parents in breeding programs and also for DNA fingerprint identification of cultivars.
Evaluation of durum wheat experimental lines under different climate and water regime conditions of Iran
Authors: Mohammadi Reza , Sadeghzadeh Davood , Armion Mohammad , Amri Ahmed
Published: February 2011

In the Mediterranean region, grain yield of durum wheat is frequently limited by both high temperature and drought during grain filling. A total of six sets of paired trials, including 18 durum experimental lines and two durum and bread wheat landraces, were conducted in the field under three moderate (no stress), warm (stress) and cold (stress) climate conditions and two different water regimes [i.e. rain-fed (terminal stress) and two supplemental irrigations (no stress)] conditions for two cropping seasons (2005–06 and 2006–07) in Iran. Several stress indices (i.e. drought, heat, and cold) obtained from grain yield data under different climate and water regime conditions were used to analyse relationships between genotypic grain yield data of 20 genotypes and their tolerance to different stresses. The additive main effect and multiplicative interaction (AMMI) analysis was also used to capture a large portion of the genotype by environment (GE) interaction sum of squares and to separate main and interaction effects. The combined ANOVA revealed significant differences between locations, water regimes (rain-fed v. irrigation) and their effects in discriminating among the genotypes. The genotypic yields in both rain-fed and irrigated conditions were positively associated (P < 0.01) at the moderate and warm locations; but were adversely correlated (P < 0.05) at cold locations, suggesting that a high-yield potential under two supplemental irrigations does not necessarily result in improved yield under rain-fed conditions. The results verified that grain yield increased in response to irrigation, but some genotypes were more sensitive to environmental differences depending on year and location. Relative reduction of grain yield due to drought was a promising trait to improve drought tolerance indirectly in warm and moderate locations. Estimates of broad-sense heritability also varied with climate conditions. Based on principal component analysis (PCA), the different stress indices tended to discriminate genotypes in dissimilar fashions. The results also indicate that it was possible to identify superior genotypes based on single and multiple abiotic stresses (drought, heat and cold). The genotypes G4 and G5 had general tolerance to the three abiotic stresses while the G19 and G15 were tolerant to drought and cold stresses and G18 and G17 were tolerant to heat stress. According to AMMI biplot analysis, the genotypes G4 and G9 were the best in terms of both mean yield and minimal GE interaction, indicating that selecting for improved yield may increase yield in a wide range of environments.
Mapping backbone and side-chain interactions in the transition state of a coupled protein folding and binding reaction
Authors: Bachmann Annett , Wildemann Dirk , Praetorius Florian , Fischer Gunter , Kiefhaber Thomas
Published: February 2011

Understanding the mechanism of protein folding requires a detailed knowledge of the structural properties of the barriers separating unfolded from native conformations. The S-peptide from ribonuclease S forms its α-helical structure only upon binding to the folded S-protein. We characterized the transition state for this binding-induced folding reaction at high resolution by determining the effect of site-specific backbone thioxylation and side-chain modifications on the kinetics and thermodynamics of the reaction, which allows us to monitor formation of backbone hydrogen bonds and side-chain interactions in the transition state. The experiments reveal that α-helical structure in the S-peptide is absent in the transition state of binding. Recognition between the unfolded S-peptide and the S-protein is mediated by loosely packed hydrophobic side-chain interactions in two well defined regions on the S-peptide. Close packing and helix formation occurs rapidly after binding. Introducing hydrophobic residues at positions outside the recognition region can drastically slow down association.
Vacuolization of mucolipidosis type II mouse exocrine gland cells represents accumulation of autolysosomes
Authors: Boonen Marielle , van Meel Eline , Oorschot Viola , Klumperman Judith , Kornfeld Stuart
Published: February 2011

We previously reported that mice deficient in UDP-GlcNAc:lysosomal enzyme GlcNAc-1-phosphotransferase (mucolipidosis type II or Gnptab −/− mice), the enzyme that initiates the addition of the mannose 6-phosphate lysosomal sorting signal on acid hydrolases, exhibited extensive vacuolization of their exocrine gland cells, while the liver, brain, and muscle appeared grossly unaffected. Similar pathological findings were observed in several exocrine glands of patients with mucolipidosis II. To understand the basis for this cell type–specific abnormality, we analyzed these tissues in Gnptab −/− mice using a combined immunoelectron microscopy and biochemical approach. We demonstrate that the vacuoles in the exocrine glands are enlarged autolysosomes containing undigested cytoplasmic material that accumulate secondary to deficient lysosomal function. Surprisingly, the acid hydrolase levels in these tissues ranged from normal to modestly decreased, in contrast to skin fibroblasts, which accumulate enlarged lysosomes and/or autolysosomes also but exhibit very low levels of acid hydrolases. We propose that the lysosomal defect in the exocrine cells is caused by the combination of increased secretion of the acid hydrolases via the constitutive pathway along with their entrapment in secretory granules. Taken together, our results provide new insights into the mechanisms of the tissue-specific abnormalities seen in mucolipidosis type II.
The Ndc80 complex uses a tripartite attachment point to couple microtubule depolymerization to chromosome movement
Authors: Tooley John G. , Miller Stephanie A. , Stukenberg P. Todd
Published: February 2011

In kinetochores, the Ndc80 complex couples the energy in a depolymerizing microtubule to perform the work of moving chromosomes. The complex directly binds microtubules using an unstructured, positively charged N-terminal tail located on Hec1/Ndc80. Hec1/Ndc80 also contains a calponin homology domain (CHD) that increases its affinity for microtubules in vitro, yet whether it is required in cells and how the tail and CHD work together are critical unanswered questions. Human kinetochores containing Hec1/Ndc80 with point mutations in the CHD fail to align chromosomes or form productive microtubule attachments. Kinetochore architecture and spindle checkpoint protein recruitment are unaffected in these mutants, and the loss of CHD function cannot be rescued by removing Aurora B sites from the tail. The interaction between the Hec1/Ndc80 CHD and a microtubule is facilitated by positively charged amino acids on two separate regions of the CHD, and both are required for kinetochores to make stable attachments to microtubules. Chromosome congression in cells also requires positive charge on the Hec1 tail to facilitate microtubule contact. In vitro binding data suggest that charge on the tail regulates attachment by directly increasing microtubule affinity as well as driving cooperative binding of the CHD. These data argue that in vertebrates there is a tripartite attachment point facilitating the interaction between Hec1/Ndc80 and microtubules. We discuss how such a complex microtubule-binding interface may facilitate the coupling of depolymerization to chromosome movement.
Filamin depletion blocks endoplasmic spreading and destabilizes force-bearing adhesions
Authors: Lynch Christopher D. , Gauthier Nils C. , Biais Nicolas , Lazar Andre M. , Roca-Cusachs Pere , Yu Cheng-Han , Sheetz Michael P.
Published: February 2011

Cell motility is an essential process that depends on a coherent, cross-linked actin cytoskeleton that physically coordinates the actions of numerous structural and signaling molecules. The actin cross-linking protein, filamin (Fln), has been implicated in the support of three-dimensional cortical actin networks capable of both maintaining cellular integrity and withstanding large forces. Although numerous studies have examined cells lacking one of the multiple Fln isoforms, compensatory mechanisms can mask novel phenotypes only observable by further Fln depletion. Indeed, shRNA-mediated knockdown of FlnA in FlnB–/–mouse embryonic fibroblasts (MEFs) causes a novel endoplasmic spreading deficiency as detected by endoplasmic reticulum markers. Microtubule (MT) extension rates are also decreased but not by peripheral actin flow, because this is also decreased in the Fln-depleted system. Additionally, Fln-depleted MEFs exhibit decreased adhesion stability that appears in increased ruffling of the cell edge, reduced adhesion size, transient traction forces, and decreased stress fibers. FlnA–/–MEFs, but not FlnB–/–MEFs, also show a moderate defect in endoplasm spreading, characterized by initial extension followed by abrupt retractions and stress fiber fracture. FlnA localizes to actin linkages surrounding the endoplasm, adhesions, and stress fibers. Thus we suggest that Flns have a major role in the maintenance of actin-based mechanical linkages that enable endoplasmic spreading and MT extension as well as sustained traction forces and mature focal adhesions.
Automated workflows for accurate mass-based putative metabolite identification in LC/MS-derived metabolomic datasets
Authors: Brown Marie , Wedge David C. , Goodacre Royston , Kell Douglas B. , Baker Philip N. , Kenny Louise C. , Mamas Mamas A. , Neyses Ludwig , Dunn Warwick B.
Published: February 2011

Motivation: The study of metabolites (metabolomics) is increasingly being applied to investigate microbial, plant, environmental and mammalian systems. One of the limiting factors is that of chemically identifying metabolites from mass spectrometric signals present in complex datasets.

Results: Three workflows have been developed to allow for the rapid, automated and high-throughput annotation and putative metabolite identification of electrospray LC-MS-derived metabolomic datasets. The collection of workflows are defined as PUTMEDID_LCMS and perform feature annotation, matching of accurate m/z to the accurate mass of neutral molecules and associated molecular formula and matching of the molecular formulae to a reference file of metabolites. The software is independent of the instrument and data pre-processing applied. The number of false positives is reduced by eliminating the inaccurate matching of many artifact, isotope, multiply charged and complex adduct peaks through complex interrogation of experimental data.

Availability: The workflows, standard operating procedure and further information are publicly available at http://www.mcisb.org/resources/putmedid.html.

Contact:  warwick.dunn@manchester.ac.uk
Proteomics to go: Proteomatic enables the user-friendly creation of versatile MS/MS data evaluation workflows
Authors: Specht Michael , Kuhlgert Sebastian , Fufezan Christian , Hippler Michael
Published: February 2011

Summary: We present Proteomatic, an operating system independent and user-friendly platform that enables the construction and execution of MS/MS data evaluation pipelines using free and commercial software. Required external programs such as for peptide identification are downloaded automatically in the case of free software. Due to a strict separation of functionality and presentation, and support for multiple scripting languages, new processing steps can be added easily.

Availability and Implementation: Proteomatic is implemented in C++/Qt, scripts are implemented in Ruby, Python and PHP. All source code is released under the LGPL. Source code and installers for Windows, Mac OS X, and Linux are freely available at http://www.proteomatic.org.

Contact:  michael.specht@uni-muenster.de

Supplementary information:  Supplementary data are available at Bioinformatics online.
What Have We Learned About Acute Pancreatitis in Children?
Authors: Bai Harrison X , Lowe Mark E , Husain Sohail Z
Published: February 2011

Pediatric pancreatitis has received much attention during the past few years. Numerous reports have identified an increasing trend in the diagnosis of acute pancreatitis in children and key differences in disease presentation and management between infants and older children. The present review provides a brief, evidence‐based focus on the latest progress in the clinical field. It also poses important questions for emerging multicenter registries to answer about the natural history and management of affected children with pancreatitis.
Measles virotherapy in a mouse model of adult T-cell leukaemia/lymphoma
Authors: Parrula Cecilia , Fernandez Soledad A. , Zimmerman Bevin , Lairmore Michael , Niewiesk Stefan
Published: February 2011

Adult T-cell leukaemia/lymphoma (ATL) is a highly aggressive CD4+T-cell malignancy caused by human T-cell leukaemia virus type 1. Measles virus (MV) oncolytic therapy has been reported to be efficient in reducing tumour burden in subcutaneous xenograft models of lymphoproliferative disorders such as myeloma, B-cell lymphoma and cutaneous T-cell lymphoma, but its potential to reduce tumour burden in disseminated lymphoproliferative disorders such as ATL remains to be determined. In this study, MV oncolytic therapy was evaluated in the MET-1/NOD/SCID xenograft mouse model of ATL. Treatment with the vaccine-related strain MV-NSE led to a significant reduction in tumour burden. In mice with a high tumour burden, therapy with MV-NSE significantly increased survival beyond any other single treatment tested previously using this model. Interestingly, signs of morbidity (cachexia) in mice treated with MV were not directly associated with tumour burden, but were correlated with the secretion of interleukin-6 by MET-1 cells and host cells. The results suggest that MV therapy could be a promising therapy for generalized lymphoproliferative disease.
Aguacate virus, a new antigenic complex of the genus Phlebovirus (family Bunyaviridae)
Authors: Palacios Gustavo , Travassos da Rosa Amelia , Savji Nazir , Sze Wilson , Wick Ivan , Guzman Hilda , Hutchison Stephen , Tesh Robert , Lipkin W. Ian
Published: February 2011

Genomic and antigenic characterization of Aguacate virus, a tentative species of the genus Phlebovirus, and three other unclassified viruses, Armero virus, Durania virus and Ixcanal virus, demonstrate a close relationship to one another. They are distinct from the other nine recognized species within the genus Phlebovirus. We propose to designate them as a new (tenth) serogroup or species (Aguacate virus) within the genus. The four viruses were all isolated from phlebotomine sandflies (Lutzomyia sp.) collected in Central and South America. Aguacate virus appears to be a natural reassortant and serves as one more example of the high frequency of reassortment in this genus.
Requirement of dopamine signaling in the amygdala and striatum for learning and maintenance of a conditioned avoidance response
Authors: Darvas Martin , Fadok Jonathan P. , Palmiter Richard D.
Published: February 2011

Two-way active avoidance (2WAA) involves learning Pavlovian (association of a sound cue with a foot shock) and instrumental (shock avoidance) contingencies. To identify regions where dopamine (DA) is involved in mediating 2WAA, we restored DA signaling in specific brain areas of dopamine-deficient (DD) mice by local reactivation of conditionally inactivated Th genes using viral gene therapy. Among all targeted areas—prefrontal cortex (PFC), amygdala, ventral striatum, dorsal striatum, and whole striatum—only restoration of DA signaling to both the whole striatum together with the amygdala enabled DD mice to acquire 2WAA. However, after prolonged overtraining during which DD mice had DA synthesis systemically reconstituted pharmacologically with L-3,4-dihydroxyphenylalanine (L-Dopa), DA signaling in the striatum alone was sufficient to maintain 2WAA, whereas DA signaling in the PFC together with the amygdala was insufficient to maintain 2WAA. Our results indicate that learning 2WAA requires DA signaling in both the amygdala and the entire striatum; however, after sufficient training, DA signaling in the striatum alone can maintain the learned avoidance behavior.
Regulation of Solute Flux through Plasmodesmata in the Root Meristem
Authors: Rutschow Heidi L. , Baskin Tobias I. , Kramer Eric M.
Published: February 2011

Plasmodesmata permit solutes to move between cells nonspecifically and without having to cross a membrane. This symplastic connectivity, while straightforward to observe using fluorescent tracers, has proven difficult to quantify. We use fluorescence recovery after photobleaching, combined with a mathematical model of symplastic diffusion, to assay plasmodesmata-mediated permeability in the Arabidopsis (Arabidopsis thaliana) root meristem in wild-type and transgenic lines, and under selected chemical treatments. The permeability measured for the wild type is nearly 10-times greater than previously reported. Plamodesmal permeability remains constant in seedlings treated with auxin (30 nm indoleacetic acid for 2 and 24 h; 100 nm indoleacetic acid for 2 h); however, permeability is diminished in two lines previously reported to have impaired plasmodesmal function as well as in wild-type seedlings treated for 24 h with 0.6 mm tryptophan. Moreover, plasmodesmal permeability is strongly altered by applied hydrogen peroxide within 2 h of treatment, being approximately doubled at a low concentration (0.6 mm) and nearly eliminated at a higher one (6 mm). These results reveal that the plasmodesmata in the root meristem carry a substantial flux of small molecules and that this flux is subject to rapid regulation.
Expression of Antibody Fragments with a ControlledN-Glycosylation Pattern and Induction of Endoplasmic Reticulum-Derived Vesicles in Seeds of Arabidopsis
Authors: Loos Andreas , Van Droogenbroeck Bart , Hillmer Stefan , Grass Josephine , Pabst Martin , Castilho Alexandra , Kunert Renate , Liang Mifang , Arcalis Elsa , Robinson David G. , Depicker Ann , Steinkellner Herta
Published: February 2011

Intracellular trafficking and subcellular deposition are critical factors influencing the accumulation and posttranslational modifications of proteins. In seeds, these processes are not yet fully understood. In this study, we set out to investigate the intracellular transport, final destination, N-glycosylation status, and stability of the fusion of recombinant single-chain variable fragments to the crystallizing fragment of an antibody (scFv-Fc) of two antiviral monoclonal antibodies (2G12 and HA78). The scFv-Fcs were expressed in Arabidopsis (Arabidopsis thaliana) seeds and leaves both as secretory molecules and tagged with an endoplasmic reticulum (ER) retention signal. We demonstrate differential proteolytic degradation of scFv-Fcs in leaves versus seeds, with higher degradation in the latter organ. In seeds, we show that secretory versions of HA78 scFv-Fcs are targeted to the extracellular space but are deposited in newly formed ER-derived vesicles upon KDEL tagging. These results are in accordance with the obtained N-glycosylation profiles: complex-type and ER-typical oligomannosidic N-glycans, respectively. HA78 scFv-Fcs, expressed in seeds of an Arabidopsis glycosylation mutant lacking plant-specific N-glycans, exhibit custom-made human-type N-glycosylation. In contrast, 2G12 scFv-Fcs carry exclusively ER-typical oligomannosidic N-glycans and were deposited in newly formed ER-derived vesicles irrespective of the targeting signals. HA78 scFv-Fcs exhibited efficient virus neutralization activity, while 2G12 scFv-Fcs were inactive. We demonstrate the efficient generation of scFv-Fcs with a controlled N-glycosylation pattern. However, our results also reveal aberrant subcellular deposition and, as a consequence, unexpected N-glycosylation profiles. Our attempts to elucidate intracellular protein transport in seeds contributes to a better understanding of this basic cell biological mechanism and is a step toward the versatile use of Arabidopsis seeds as an alternative expression platform for pharmaceutically relevant proteins.
Improvements in haemolysis and indicators of erythrocyte survival do not correlate with acute vaso‐occlusive crises in patients with sickle cell disease: a phase III randomized, placebo‐controlled, double‐blind study of the gardos channel blocker senicapoc (ICA‐17043)
Authors: Ataga Kenneth I. , Reid Marvin , Ballas Samir K. , Yasin Zahida , Bigelow Carolyn , James Luther St. , Smith Wally R. , Galacteros Frederic , Kutlar Abdullah , Hull James H. , Stocker Jonathan W. ,   for the ICA‐17043‐10 Study Investigators
Published: February 2011

Red blood cell (RBC) hydration is regulated in part by the Ca2+‐activated K+ efflux (Gardos) channel. Senicapoc selectively blocks potassium efflux through the Gardos channel, reducing RBC dehydration and haemolysis, and increasing haemoglobin levels in sickle cell disease (SCD). This randomized, placebo‐controlled trial was designed to determine the safety and clinical efficacy of senicapoc in SCD patients. One hundred and forty‐five patients were randomized to receive senicapoc and 144 patients to receive placebo for 52 weeks. Consistent with a previous study, patients in the senicapoc group had significantly increased haematocrit, haemoglobin, and decreased numbers of both dense erythrocytes and reticulocytes when compared to the placebo group. The unblinded Data Monitoring Committee terminated this study early due to a lack of efficacy when it determined that, despite improvements in anaemia and haemolysis, no significant improvement in the rate of sickle cell painful crises was observed in patients treated with senicapoc compared to those on placebo (0·38 vs. 0·31, respectively). Comparisons of the times to first, second and third crises between the senicapoc and placebo groups were not statistically significant. Nausea and urinary tract infections occurred more frequently in the senicapoc group than placebo. Serious adverse events were similar in the two groups.
Red cell alloimmunization in a diverse population of transfused patients with thalassaemia
Authors: Thompson Alexis A. , Cunningham Melody J. , Singer Sylvia T. , Neufeld Ellis J. , Vichinsky Elliott , Yamashita Robert , Giardina Patricia , Kim Hae‐Young , Trachtenberg Felicia , Kwiatkowski Janet L. ,   for the Thalassemia Clinical Research Network Investigators
Published: February 2011

Red blood cell (RBC) transfusion is the primary treatment for severe forms of thalassaemia. Pre‐storage screening has resulted in decreased transfusion‐transmitted infections, but anti‐RBC antibodies remain a major problem. We report on 697 participants who had ever received transfusions. Allo‐ and autoantibody rates were compared with respect to splenectomy status, ethnicity, diagnosis, duration of transfusions, treatment centre, and age at transfusion initiation, together with rates before and after 1990, when leucoreduction methods were routine at thalassaemia treatment centres. Allo‐ and autoantibodies were reported in 115 (16·5%) and 34 (4·9%) subjects, respectively. Splenectomized patients were more likely to have alloantibodies [odds ratio (OR) = 2·528, P ≤ 0·0001], or autoantibodies (OR = 2·590, P = 0·0133). Alloantibodies occurred in 19 of 91 (21%) splenectomized subjects who started transfusion after 1990, and only 18 of 233 (7·7%) nonsplenectomized subjects (P < 0·001). Data from this study demonstrate that RBC antibodies continue to develop in chronically transfused thalassaemia patients at a high rate. Splenectomy preceded the development of antibodies in most cases. Increased rates of RBC sensitization among splenectomized patients is concerning and deserves further study.
The impacts and implications of an intensifying fire regime on Alaskan boreal forest composition and albedo
Authors: BECK PIETER S. A. , GOETZ SCOTT J. , MACK MICHELLE C. , ALEXANDER HEATHER D. , JIN YUFANG , RANDERSON JAMES T. , LORANTY M. M.
Published: February 2011

Climate warming and drying are modifying the fire dynamics of many boreal forests, moving them towards a regime with a higher frequency of extreme fire years characterized by large burns of high severity. Plot‐scale studies indicate that increased burn severity favors the recruitment of deciduous trees in the initial years following fire. Consequently, a set of biophysical effects of burn severity on postfire boreal successional trajectories at decadal timescales have been hypothesized. Prominent among these are a greater cover of deciduous tree species in intermediately aged stands after more severe burning, with associated implications for carbon and energy balances. Here we investigate whether the current vegetation composition of interior Alaska supports this hypothesis. A chronosequence of six decades of vegetation regrowth following fire was created using a database of burn scars, an existing forest biomass map, and maps of albedo and the deciduous fraction of vegetation that we derived from Moderate Resolution Imaging Spectroradiometer (MODIS) satellite imagery. The deciduous fraction map depicted the proportion of aboveground biomass in deciduous vegetation, derived using a RandomForest algorithm trained with field data sets (n=69, 71% variance explained). Analysis of the difference Normalized Burn Ratio, a remotely sensed index commonly used as an indicator of burn severity, indicated that burn size and ignition date can provide a proxy of burn severity for historical fires. LIDAR remote sensing and a bioclimatic model of evergreen forest distribution were used to further refine the stratification of the current landscape by burn severity. Our results show that since the 1950s, more severely burned areas in interior Alaska have produced a vegetation cohort that is characterized by greater deciduous biomass. We discuss the importance of this shift in vegetation composition due to climate‐induced changes in fire severity for carbon sequestration in forest biomass and surface reflectance (albedo), among other feedbacks to climate.
Nurses’ and midwives’ clinical leadership development needs: A mixed methods study
Authors: Casey Mary , McNamara Martin , Fealy Gerard , Geraghty Ruth
Published: February 2011

casey m., mcnamara m., fealy g. & geraghty r. (2011) Nurses’ and midwives’ clinical leadership development needs: a mixed methods study. Journal of Advanced Nursing67(7), 1502–1513.

Aim.  This paper is a report of a descriptive study of nurses’ and midwives’ clinical leadership development needs.

Background.  Nurses and midwives are expected to fulfil a leadership role at all levels, yet efforts to strategically support them are often unfocused. An analysis of clinical leadership development needs can provide the foundation for leadership initiatives to support staff.

Method.  A mixed methods design was used. A questionnaire was sent to 911 nurses and midwives and 22 focus groups comprising 184 participants were conducted. Data were collected between March and June 2009 across all promotional grades of nurses and midwives in Ireland. Repeated measures anova with Greenhouse–Geisser adjustment was used for post hoc pair wise comparisons of the subscale dimensions of clinical leadership. anova with Tukey’s post hoc method was used for comparison between grades on each individual subscale. Thematic analysis was undertaken on the focus group data.

Results.  Results reveal that needs related to development of the profession were the highest for all grades. The staff grade expressed a higher need in relation to ‘managing clinical area’, ‘managing the patient care’ and ‘skills for clinical leadership’ than managers. Qualitative analysis yielded five themes; (1) clinical leadership and leaders from a nursing and midwifery perspective; (2) quality service from a nursing and midwifery perspective; (3) clinical leaders’ roles and functions; (4) capital and (5) competences for clinical leaders and leadership and the context of clinical leadership.

Conclusion.  Clinical leadership concerns quality, safety and effectiveness. Nurses and midwives are ideally placed to offer the clinical leadership that is required to ensure these patient care outcomes. Development initiatives must address the leader and leadership competencies to support staff.
Oral glucose for pain relief during eye examinations for retinopathy of prematurity
Authors: Olsson Emma , Eriksson Mats
Published: February 2011

Aim.  The aim of this study was to determine whether oral glucose could have a pain‐relieving effect during the eye examinations that premature neonates undergo in the screening for retinopathy of prematurity.

Background.  Studies have shown that orally administered sweet‐tasting solutions reduce signs of pain during painful procedures such as venepuncture and heel sticks on premature and full‐term infants. This effect has not yet been proven during the eye examinations for the screening of retinopathy of prematurity.

Design.  Randomised, controlled, double‐blind study.

Method.  Thirty infants born before 32 weeks of gestation and/or weighing <1500 g at birth were randomised to receive 1 ml of either 30% glucose or sterile water before the eye examination. Examinations were videotaped, and the observer was blinded to the intervention. Pain responses were scored using the premature infant pain profile. Heart rate and crying time were also recorded.

Results.  There were no statistically significant differences between the two groups, neither in premature infant pain profile score, heart rate changes nor crying time.

Conclusion.  This study does not support the pain‐relieving effect of orally administered glucose during eye examinations in preterm infants.

Relevance to clinical practice.  Oral glucose should not be used as single measure for pain relief during eye examinations of preterm infants. Other comforting and pain‐relieving measures should be used.
Single subcutaneous dosing of cefovecin in rhesus monkeys (Macaca mulatta): a pharmacokinetic study
Authors: BAKKER J. , THUESEN L. R. , BRASKAMP G. , SKAANILD M. T. , OUWERLING B. , LANGERMANS J. A. M. , BERTELSEN M. F.
Published: February 2011

Bakker, J., Thuesen, L. R., Braskamp, G., Skaanild, M. T., Ouwerling, B., Langermans, J. A. M., Bertelsen, M. F. Single subcutaneous dosing of cefovecin in rhesus monkeys (Macaca mulatta): a pharmacokinetic study. J. vet. Pharmacol. Therap.34, 464–468.

Cefovecin is a third‐generation cephalosporin approved for antibacterial treatment with a 14‐day dosing interval in dogs and cats. This antibiotic may also be useful for zoo and wildlife veterinary medicine, because of its broad spectrum and long duration of activity. The aim of the study was to determine whether cefovecin is a suitable antibiotic to prevent skin wound infection in rhesus monkeys. Therefore, the pharmacokinetics (PK) of cefovecin after a single subcutaneous injection at 8 mg/kg bodyweight in four rhesus monkeys (Macaca mulatta) and sensitivity of bacterial isolates from fresh skin wounds were determined. After administration, blood, urine, and feces were collected, and concentrations of cefovecin were determined. Further, the minimum inhibitory concentrations (MIC) for bacteria isolated from fresh skin wounds of monkeys during a health control program were determined. The mean maximum plasma concentration (Cmax) of cefovecin was 78 μg/mL and was achieved after 57 min. The mean apparent long elimination half‐life (t½) was 6.6 h and excretion occurred mainly via urine. The MIC for the majority of the bacteria examined was >100 μg/mL. The PK of cefovecin in rhesus monkeys is substantially different than for dogs and cats. Cefovecin rapidly reached Cmax which however was lower than most of the MIC levels and with a very short t½. Therefore, cefovecin is not recommended for treating skin wounds in rhesus monkeys.
Can piperonyl butoxide enhance the efficacy of pyrethroids against pyrethroid‐resistant Aedes aegypti?
Authors: Bingham Georgina , Strode Clare , Tran Lien , Khoa Pham Thi , Jamet Helen Pates
Published: February 2011

Background  Pyrethroid resistance can be considered the main threat to the continued control of many mosquito vectors of disease. Piperonyl butoxide (PBO) has been used as a synergist to help increase the efficacy of certain insecticides. This enhancement stems from its ability to inhibit two major metabolic enzyme systems, P450s and non‐specific esterases, and to enhance cuticular penetration of the insecticide.

Objective  To compare the mortality of a characterized resistant Aedes aegypti strain, Nha Trang, from Vietnam and the susceptible laboratory strain Bora Bora on netting with the pyrethroid deltamethrin (DM) alone and in combination with PBO.

Methods  Resistance mechanisms were characterized using molecular and bioassay techniques; standard PCR was used to test for the kdr target site mutation. Potential genes conferring metabolic resistance to DM were identified with microarray analysis using the Ae. aegypti‘detox chip’. These data were analysed alongside results from WHO susceptibility tests. P450, CYP9J32, was significantly overexpressed in the DM‐resistant strain compared with the susceptible Bora Bora strain. Another five genes involved with oxidative stress responses in mosquitoes were also significantly overexpressed. The Nha Trang strain was homozygous for two kdr mutations. WHO cone bioassays were used to investigate mortality with incorporated DM‐treated nets with and without PBO. PBO used in combination with DM resulted in higher mortality than DM alone.

Conclusion  Synergists may have an important role to play in the future design of vector control products in an era when alternatives to pyrethroids are scarce.
Functional characterization of the TSC2 c.3598C>T (p.R1200W) missense mutation that co‐segregates with tuberous sclerosis complex in mildly affected kindreds
Authors: Wentink M , Nellist M , Hoogeveen‐Westerveld M , Zonnenberg B , van der Kolk D , van Essen T , Park S‐M , Woods G , Cohn‐Hokke P , Brussel W , Smeets E , Brooks A , Halley D , van den Ouweland A , Maat‐Kievit A
Published: February 2011

Wentink M, Nellist M, Hoogeveen‐Westerveld M, Zonnenberg B, van der Kolk D, van Essen T, Park S‐M, Woods G, Cohn‐Hokke P, Brussel W, Smeets E, Brooks A, Halley D, van den Ouweland A, Maat‐Kievit A. Functional characterization of the TSC2 c.3598C>T (p.R1200W) missense mutation that co‐segregates with tuberous sclerosis complex in mildly affected kindreds.

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by a combination of neurological symptoms and hamartomatous growths, and caused by mutations in the TSC1 and TSC2 genes. Overall, TSC2 mutations are associated with a more severe disease phenotype. We identified the c.3598C>T (R1200W) change in the TSC2 gene in seven different families. The clinical phenotypes in the families were mild, characterized by mild skin lesions, remitting epilepsy and a lack of severe mental retardation or major organ involvement. Functional analysis of the TSC2 R1200W variant, and four other TSC2 missense variants associated with a mild TSC phenotype, confirmed that the changes disrupted the TSC1–TSC2 function. Interestingly however, in each case, the TSC1–TSC2 interaction was not affected by the amino acid substitution.
Training of trainers on epinephrine autoinjector use
Authors: Arga Mustafa , Bakirtas Arzu , Catal Ferhat , Derinoz Oksan , Harmanci Koray , Razi Cem H. , Ergöcen Salih , Demirsoy M. Sadik , Turktas Ipek
Published: February 2011

To cite this article: Arga M, Bakirtas A, Catal F, Derinoz O, Harmanci K, Razi CH, Ergöcen S, Demirsoy MS, Turktas I. Training of trainers on epinephrine autoinjector use. Pediatric Allergy Immunology 2011; 22: 590–593.

The majority of physicians do not know how to use epinephrine autoinjectors. This displays that current education of physicians on anaphylaxis is inadequate for a thorough practice. We hypothesize that a theoretical lecture together with a practical session on epinephrine autoinjector use will improve its proper use by physicians. Residents, specialists, and consultants from General Pediatrics excluding allergists and allergy fellows were included in this study. All physicians were given an eight‐item questionnaire followed by a practical session scoring and timing ability to use epinephrine autoinjector trainer. This ensued with one‐to‐one hands‐on training on correct autoinjector use. Finally, a joint theoretical lecture on anaphylaxis including re‐demonstration of epinephrine autoinjector use was given. All physicians were scored a second time on use of epinephrine autoinjector 6 months later. One hundred fifty‐one of 196 participants completed all steps of the study in four tertiary hospitals. Correct use of epinephrine autoinjector improved from 23.3% to 74.2%, mean score from 3.49 ± 1.14 to 4.66 ± 0.65, need for prospectus from 91.4% to 29.1%, and mean time to administer autoinjector from 28.01 ± 6.22 s to 19.62 ± 5.01 s (p < 0.001 for each). The rate of most common mistakes during autoinjector use decreased but the ranking did not change. An integrated theoretical and practical education increased correct of epinephrine autoinjector use by physicians. Ongoing mistakes despite this education may be related with its design.
Stochastic simulation of dairy cattle breeding schemes: Genetic evaluation of nucleus size and type
Authors: Schrooten C. , van Arendonk J. A. M.
Published: February 2011

A stochastic model was developed for the simulation of dairy cattle breeding programmes including use of embryo transfer and nucleus schemes. All bulls in the model were simulated individually. In order to reduce the computational demands only nucleus and top population cows were simulated individually while the commercial cow population was simulated by age groups with a deterministic model. Selection was for a single sex‐limited trait with a heritability of 0.25 and based on animal model breeding value estimates. Selection of dams was across age classes while sires were required to have a progeny test before they could be selected as proven bull or bull sire. The first 15 years of the simulated period was used to reach a population with an equilibrium genetic progress for a progeny testing scheme. Comparisons were based on the 25 year period after an alternative breeding scheme was adopted in year 15.

The progeny testing scheme without MOET resulted in an annual genetic progress of .234 σA. The annual genetic response in open MOET nucleus schemes with 120 and 240 replacement heifers per year was 4.3% and 5.6% higher, respectively, than in the progeny testing scheme. The response was reduced by 1.7% and 0.9% when the nucleus schemes with 120 and 240 replacements heifers per year were closed.

Stochastische Simulation von Milchviehzuchtplänen: Genetische Bewertung von Nukleusgröße und Typ

Ein stochastisches Modell wurde für die Simulation eines Zuchtprogrammes mit Embryotransfer und Nukleus entwickelt. Alle Bullen wurden im Modell individuell simuliert. Um die Rechenansprüche zu begrenzen, wurden nur Nukleus‐ und Spitzenpopulationskühe individuell simuliert, während die kommerzielle Kuhpopulation deterministisch nach Altersgruppen simuliert wurde. Selektion betraf ein einzelnes geschlechtsgebundenes Merkmal mit einer Heritabilität von 25% und beruhte auf einem Tiermodell. Die Selektion der Muttertiere erfolgte über Altersklassen hinweg, während Vatertiere vor ihrer Selektion als geprüfte oder Elitebullen eine Nachkommenschaftsprüfung haben mußten. Die ersten 15 Jahre der simulierten Periode wurden bis zum Erreichen eines Gleichgewichtsfortschrittes des Nachkommenschaftsprüfsystems benötigt. Die Vergleiche beruhen auf der folgenden 25 Jahrperiode, nachdem im Jahr 15 ein alternatives Zuchtsystem eingeführt worden war.

Nachkommenschaftsprüfschema ohne MOET resultierte in einen Jahreszuchtfortschritt von 0,234 σA. Der jährliche genetische Fortschritt im offenen MOET Nukleusschema mit 120 und 240 nachgestellten Kalbinnen pro Jahr war 4,3 bzw. 5,6% höher als beim Nachkommenschaftsprüfsystem. Der Fortschritt wurde um 1,7 bzw. 0,9% reduziert, wenn die Nukleusschema geschlossen worden sind.
Liposome mediated gene transfer via spermatozoa into avian egg cells
Authors: Rottmann O.J. , Antes R. , Höfer P. , Maierhofer G.
Published: February 2011

Liposomes were prepared in the presence of plasmid DNA and allowed to react with spermatozoa from roosters prior to artificial insemination of 200 hens. Twelve days old fetuses developed from fertilized eggs were analysed by Southern blot technique to detect the transfer of the foreign sequences. About 26% of all fetuses examined displayed the banding pattern of the transferred plasmid. The results indicate that the sequences are not chromosomally integrated but are present in episomic form. The method described here is easy to handle so that it may become an appropriate means to establish large numbers of transgenic animals.

Liposomaler Gentransfer über Spermien in Hühnereier

Mischsperma von mehreren Hähnen wurde mit Liposomen inkubiert, in denen Plasmid‐DNA eingeschlossen war. Mit diesem Sperma sind 200 Hennen inseminiert worden. Nach 12 Tagen Bebrütung wurden die Föten mittels Southernblot‐Technik analysiert. Rund 26% aller untersuchten Föten zeigten die typischen Bandenmuster des transferierten Plasmids. Die Befunde weisen darauf hin, daß das Plasmid nicht chromosomal integriert, sondern als Episom neben der genomischen DNA vorliegt. Das hier beschriebene Gentransfer‐Verfahren ist einfach zu handhaben, so daß ohne nennenswerten Aufwand größere Zahlen transgener Tiere erstellt werden können.
Factoring out common terms in the mixed model equations
Authors: Tier B.
Published: February 2011

In the coefficient matrix of the mixed model equations (MME) for the multiple trait animal and reduced animal models of animal breeding there is considerable repetition of some coefficients. This paper describes how some of these common terms can be factored out when iterating for solutions. As a result considerable savings in computation are possible.

Ausklammern gemeinsamer Größen in Mischmodellgleichungen

In der Koeffizientenmatrix gemischter Modellgleichungen (MME) für Mehrmerkmals‐ und reduzierte Tiermodelle gibt es beträchtliche Wiederholungen einzelner Koeffizienten. Die Arbeit beschreibt, wie solche gemeinsame Größen für Iteration herausgenommen werden können. Es können beträchtliche Recheneinsparungen erzielt werden.
A modified pseudoexpectation method for variance component estimation
Authors: Iwaisaki H.
Published: February 2011

A set of quadratic forms that are translation invariant and whose matrices are not symmetric are considered. Using the quadratics, a modified pseudoexpectation method for estimating variance components is discussed. Whereas this method does not require calculation of the inverse of the coefficient matrix of mixed model equations as other pseudoexpectation methods do not, weighted sums of squares of off‐diagonal elements of the coefficient matrix need to be computed in each iteration. A simple simulation study conducted suggests that the current method gives an estimator closer to REML estimator and would have a better ability to account for culling type of selection than previous pseudoexpectation methods.

Eine modifizierte Pseudo‐Erwartungswert‐Methode zur Varianzkomponentenschätzung

Eine Reihe von quadratischen Formen, translationsinvariant mit nicht symmetrischen Matrizen, wurden untersucht. Durch Verwendung quadratischer Formen wird eine modifizierte Pseudo‐Erwartungswert‐Methode zur Schätzung von Varianzkomponenten betrachtet. Die Methode benötigt zwar nicht die Inverse der Koeffizientenmatrix, doch müssen gewichtete Quadratsummen der nicht‐diagonalen Elemente der Koeffizientenmatrix bei jeder Situation berechnet werden. Eine einfache Simulationsstudie deutet an, daß die Methode einen Schätzwert ergibt, der näher am REML‐Wert liegt und besser Abschnittsselektion in Rechnung stellt, als frühere Pseudo‐Erwartungswert‐Methoden.