bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seeking feedback in blended learning: competitive versus cooperative student attitudes and their links to learning outcome
Authors: Hwang A. , Arbaugh J.B. 
Published: March 2009

AbstractEmerging research has revealed the impact of electronic media usage on student outcomes, such as satisfaction and reported learning efficacy. However, little is known of its impact on measurable knowledge acquisition. Results from this study showed that participation on discussion topics through Blackboard, an electronic discussion forum, predicted multiple‐choice test performance. In contrast, none of the traditional face‐to‐face feedback‐seeking behaviours, neither with professors in class or out of class, nor among fellow students, had significant influence on test results. An examination of underlying attitudes driving both electronic and face‐to‐face feedback‐seeking behaviours showed that competitiveness rather than cooperation drove average intensity of electronic board participation, which in turn, was related to participation across the number of electronic topical forums. The influencing role of competitiveness in this undergraduate student sample may indicate undergraduate students' lack of workplace experience, where cooperation rather than competition is often needed for workplace effectiveness. This and implications of other findings are discussed in the paper.
From bar diagrams to letter‐symbolic algebra: a technology‐enabled bridging
Authors: Looi C.‐K. , Lim K.‐S. 
Published: March 2009

AbstractIn the Singapore primary school Mathematics curriculum, students are taught the model method that uses bar diagrams to visualize the problem structure in a given word problem. When these students progress to secondary school, they learn the algebraic way of solving word problems. Studies (e.g. Ng et al.) have shown that poor bridging of students from the use of bar diagrams to the use of letter‐symbolic algebraic methods can hinder their learning of algebra. We design a software tool ‘AlgeBAR’ to scaffold the learning of the algebraic process, especially the formulation of equations to support a pedagogy that seeks to help students transit from bar diagrams to algebraic methods. In this paper, we report a cycle of evaluation of the intervention pedagogy by examining a class that uses the software tool as part of a holistic intervention package. This evaluation is in the context of an overall design research approach that sought to address complex problems in real classroom contexts in collaboration with practitioners and to integrate design principles with technological affordances to render plausible solutions. Our findings show that the software tool can be an important enabler of the bridging process.
Water and nutrients alter herbaceous competitive effects on tree seedlings in a semi‐arid savanna
Authors: Van Der Waal Cornelis , De Kroon Hans , De Boer Willem F. , Heitkönig Ignas M. A. , Skidmore Andrew K. , De Knegt Henrik J. , Van Langevelde Frank , Van Wieren Sipke E. , Grant Rina C. , Page Bruce R. , Slotow Rob , Kohi Edward M. , Mwakiwa Emmanuel , Prins Herbert H. T. 
Published: March 2009

Summary

Globally, both climatic patterns and nitrogen deposition rates show directional changes over time. It is uncertain how woody seedlings, which coexist with herbaceous plants in savannas, respond to concurrent changes in water and nutrient availability.
We investigated competition effects between herbaceous vegetation and tree seedlings (Colophospermum mopane) under changed water and nutrient (fertilized) conditions in a garden experiment situated in a semi‐arid savanna.
Herbaceous competition significantly suppressed woody seedling growth. The effect of herbaceous competition on woody seedling growth remained constant with both increasing water and nutrient availability. However, during a wet‐season drought, herbaceous competition apparently caused premature leaf senescence in non‐irrigated treatments. Fertilization exacerbated negative competition effects during the drought, while irrigation prevented leaf loss of tree seedlings in spite of herbaceous competition and fertilization.
Based on a conceptual model, we propose that the vigorous response of herbaceous plants to increased nutrient availability leads to faster depletion of soil water, which increasingly causes water stress in woody seedlings if the interval between watering events is prolonged, e.g. during wet‐season droughts.
Synthesis. Our data support the notion that changes in drought frequency are of greater importance to woody recruitment success than changes in annual rainfall amount. Based on the water and nutrient interactions observed in our experiment, we suggest that the effect of increased nitrogen deposition on woody seedling recruitment is contingent on water availability.
Molecular basis of the RHD gene in blood donors with DEL phenotypes in Shanghai
Authors: Li Q. , Hou L. , Guo Z.‐H. , Ye L‐Y. , Yue D‐Q. , Zhu Z‐Y. 
Published: March 2009

Background and Objectives  The purpose of the work was to analyse the genotype of D‐elute (DEL) samples and to elucidate whether there were novel DEL alleles in Chinese population.Materials and Methods  D‐negative samples were identified by an indirect antiglobulin test (IAT), and absorption∖elution tests to screen weak D, partial D and DEL phenotypes. DELs were further analysed by multiplex PCR, PCR‐sequence‐specific primers (PCR‐SSP) and sequencing. Some of the DEL samples were determined to show RHD zygosity by PCR‐restriction fragment length polymorphism or real‐time quantitative PCR.Results  Of 400 253 samples from individual donations, 1585 (0·40%) were typed as D negative. Among these D‐negative samples, 279 DELs were observed. Two hundred and sixty‐eight DELs were confirmed to have the RHD (K409 K) allele. Three DELs seemed to have RHD‐CE‐D hybrid alleles, including one RHD‐CE(4–9)‐D, one RHD‐CE(2–5)‐D and one suspected RHD(1–9)‐CE. Five novel RHD alleles were found among the rest of the DEL samples, including four RHD 3 g > a, one RHD (R10W), one RHD (L18P), one RHD (L84P) and one RHD (A137E). Eighty‐four DELs were analysed for Rhesus box zygosity, there were 77 RHD+/RHD–and seven RHD+/RHD+.Conclusion  About 4·35% apparent D negative Chinese individuals were weak D or partial D, while 17·60% were DEL. Novel DEL alleles are rare, and all but 11 of the 279 DELs were due to the most common DEL allele, RHD (K409 K). The RHD 3G > A might be the second most frequent DEL allele in Chinese. Exploration of a complete molecular basis for DEL in Chinese ethnic groups is a long‐term endeavour.
Orthopedic disability and socioemotional functioning
Authors: Yagmurlu M. Firat , Yagmurlu Bilge , Yilmaz Muberra 
Published: March 2009

AbstractBackground:  The major aim of the study was to examine self‐concept, emotional stability, and sociability of Turkish adolescents with orthopedic disability, and the links between these domains and sport participation.Method:  Participants of the study were 95 students in grades 5–12 (mean age, 15.44 ± 2.40 years). They were recruited from two boarding schools established for youth with orthopedic disabilities. Parents of the adolescents participated in the study by completing a form to provide information about the child, his/her condition (e.g. first appearance, severity, treatment), and the household in general. Adolescents filled in self‐report scales that were developed to measure self‐concept, emotional stability, and sociability.Results:  Hierarchical multiple regression indicated that regular engagement in sports significantly predicted self‐concept of adolescents with orthopedic disability, and the predictive value of playing sport was significant even after differences in participant age, sex, and severity of the disability were taken into account. Emotional stability and sociability of adolescents with disability were predicted by sports playing but to a low degree.Conclusion:  Study findings underline the importance of understanding social aspects of disability, and the positive association between playing sports and an individuals positive beliefs about oneself.
Abnormal iron metabolism and oxidative stress in mice expressing a mutant form of the ferritin light polypeptide gene
Authors: Barbeito Ana G. , Garringer Holly J. , Baraibar Martin A. , Gao Xiaoying , Arredondo Miguel , Núñez Marco T. , Smith Mark A. , Ghetti Bernardino , Vidal Ruben 
Published: March 2009

AbstractInsertional mutations in exon 4 of the ferritin light chain (FTL) gene are associated with hereditary ferritinopathy (HF) or neuroferritinopathy, an autosomal dominant neurodegenerative disease characterized by progressive impairment of motor and cognitive functions. To determine the pathogenic mechanisms by which mutations in FTL lead to neurodegeneration, we investigated iron metabolism and markers of oxidative stress in the brain of transgenic (Tg) mice that express the mutant human FTL498‐499InsTC cDNA. Compared with wild‐type mice, brain extracts from Tg (FTL‐Tg) mice showed an increase in the cytoplasmic levels of both FTL and ferritin heavy chain polypeptides, a decrease in the protein and mRNA levels of transferrin receptor‐1, and a significant increase in iron levels. Transgenic mice also showed the presence of markers for lipid peroxidation, protein carbonyls, and nitrone–protein adducts in the brain. However, gene expression analysis of iron management proteins in the liver of Tg mice indicates that the FTL‐Tg mouse liver is iron deficient. Our data suggest that disruption of iron metabolism in the brain has a primary role in the process of neurodegeneration in HF and that the pathogenesis of HF is likely to result from a combination of reduction in iron storage function and enhanced toxicity associated with iron‐induced ferritin aggregates in the brain.
α‐Synuclein induces migration of BV‐2 microglial cells by up‐regulation of CD44 and MT1‐MMP
Authors: Kim Seonghan , Cho Seo‐Hyun , Kim Ka Young , Shin Ki Young , Kim Hye‐Sun , Park Cheol‐Hyoung , Chang Keun‐A , Lee Sang Hyung , Cho Daeho , Suh Yoo‐Hun 
Published: March 2009

AbstractAlthough there is known to be a marked concentration of reactive microglia in the substantia nigra pars compacta (SNpc) of patients with Parkinson’s disease (PD), a disorder in which α‐synuclein plays a key pathogenic role, the specific roles of α‐synuclein and microglia remains poorly understood. In this study, we investigated the effects of α‐synuclein and the mechanisms of invasive microglial migration into the SNpc. We show that α‐synuclein up‐regulates the expressions of the cell adhesion molecule CD44 and the cell surface protease membrane‐type 1 matrix metalloproteinase through the extracellular regulated kinases 1/2 pathway. These concurrent inductions increased the generation of soluble CD44 to liberate microglia from the surrounding extracellular matrix for migration. The effects of α‐synuclein were identical in BV‐2 murine microglial cells subjected to cDNA transfection and extracellular treatment. These inductions in primary microglial cultures of C57Bl/6 mice were identical to those in BV‐2 cells. α‐Synuclein‐induced microglial migration into the SNpc was confirmed in vivo using a 6‐hydroxydopamine mouse model of PD. Our data demonstrate a correlation between α‐synuclein‐induced phenotypic changes and microglial migration. With the recruitment of the microglial population into the SNpc during dopaminergic neurodegeneration, α‐synuclein may play a role in accelerating the pathogenesis of PD.
Apoptosis pathways and their therapeutic exploitation in pancreatic cancer
Authors: Fulda Simone 
Published: March 2009

Abstract

Introduction
Pancreatic cancer
Apoptosis pathways
Exploiting apoptosis pathways for pancreatic cancer therapy
Conclusions

Resistance to apoptosis (programmed cell death) is a characteristic feature of human malignancies including pancreatic cancer, which is one of the leading causes of cancer deaths in the western world. Defects in this intrinsic cell death program can contribute to the multistep process of tumorigenesis, because too little cell death can disturb tissue homeostasis. Further, blockade of apoptosis pathways can cause treatment failure, because intact apoptosis signalling cascades largely mediate therapy‐induced cytotoxicity. The elucidation of apoptosis pathways in pancreatic carcinoma over the last decade has resulted in the identification of various molecular defects. How apoptosis pathways can be exploited for the treatment of pancreatic cancer will be discussed in this review.
Presenilin‐2 dampens intracellular Ca2+ stores by increasing Ca2+ leakage and reducing Ca2+ uptake
Authors: Brunello Lucia , Zampese Enrico , Florean Cristina , Pozzan Tullio , Pizzo Paola , Fasolato Cristina 
Published: March 2009

AbstractWe have previously shown that familial Alzheimer’s disease mutants of presenilin‐2 (PS2) and, to a lesser extent, of presenilin‐1 (PS1) lower the Ca2+ concentration of intracellular stores. We here examined the mechanism by which wild‐type and mutant PS2 affect store Ca2+ handling. By using HeLa, SH‐SY5Y and MEFs as model cells, and recombinant aequorins as Ca2+ probes, we show evidence that transient expression of either wild‐type or mutant PS2 increases the passive Ca2+ leakage: both ryanodine‐ and IP3‐receptors contribute to Ca2+ exit out of the ER, whereas the ribosome translocon complex is not involved. In SH‐SY5Y cells and MEFs, wild‐type and mutant PS2 potently reduce the uptake of Ca2+ inside the stores, an effect that can be counteracted by over‐expression of SERCA‐2B. On this line, in wild‐type MEFs, lowering the endogenous level of PS2 by RNA interference, increases the Ca2+‐loading capability of intracellular stores. Furthermore, we show that in PS double knockout MEFs, reduction of Ca2+ stores is mimicked by the expression of PS2‐D366A, a loss‐of‐function mutant, uncleaved because also devoid of presenilinase activity but not by co‐expression of the two catalytic active fragments of PS2. In summary, both physiological and increased levels of wild‐type and mutant PS2 reduce the Ca2+ uptake by intracellular stores. To exert this newly described function, PS2 needs to be in its full‐length form, even if it can subsequently be cleaved.
Platelet‐poor plasma stimulates the proliferation but inhibits the differentiation of rat osteoblastic cells in vitro
Authors: Hamdan Ahmad Abdel‐Salam , Loty Sabine , Isaac Juliane , Bouchard Philippe , Berdal Ariane , Sautier Jean‐Michel 
Published: March 2009

AbstractIntroduction: Recent studies have shown that the use of platelet preparations in bone and implant surgery might stimulate bone formation. However, the biological mechanisms are not well understood. Moreover, few studies have attempted to evaluate the effect of platelet‐poor plasma (PPP), which is a product of the platelet‐rich plasma preparation process.Objective: Thus, this study investigated the behavior of osteoblasts isolated from fetal rat calvaria cultivated in the presence of homologous PPP.Material and Methods: PPP was obtained by centrifugation of the rat mother's blood and used in replacement of fetal calf serum, which is classically used in primary culture procedures. Proliferation was measured by an MTT assay at 24, 48, and 72 h. Real‐time PCR was performed to study the expression of Runx2, Dlx5, and osteocalcin (OC) on days 0 (4 h), 1, 3, 7, and 12.Results: Alkaline phosphatase (ALP) biochemical activity was evaluated on days 0 (4 h), 1, 3, 7, and 12. Observations by phase‐contrast microscopy showed that osteoblasts were able to differentiate until the mineralization of the matrix in the presence of PPP. PPP enhanced the proliferation significantly compared with the control group (P≤0.001). PCR results showed that Runx2, Dlx5, and OC were expressed by cells in the experimental group at lower levels compared with the control group. Biochemical assay of ALP showed a lower activity in the experimental group compared with the control group (P<0.001).Conclusion: These results suggest that, in the presence of homologous PPP, rat osteoblastic cells are able to maintain their phenotype, with a higher rate of proliferation. However, PPP seems to inhibit osteoblastic differentiation.
Unique epidermolytic bullous dermatosis with associated lethal cardiomyopathy related to novel desmoplakin mutations
Authors: Asimaki Angeliki , Syrris Petros , Ward Deirdre , Guereta Luis G. , Saffitz Jeffrey E. , McKenna William J. 
Published: March 2009

Background:  Desmoplakin plays a vital role in cell adhesion, linking the transmembrane desmosomal complex to the cytoskeletal network. Clues to the biological significance of desmoplakin have emerged from the embryonic lethal phenotype of null mice and from naturally occurring human desmoplakin mutations, which cause cardiocutaneous phenotypes.Index case:  In this study, we describe a child who presented with the unique constellation of bullous dermatosis, profound plantar keratoderma, alopecia totalis and cardiomyopathy leading to sudden cardiac death at the age of 9 years.Results:  This complex cardiocutaneous phenotype is associated with compound heterozygosity for two novel nonsense desmoplakin mutations. Histological examination of a plantar skin biopsy showed full thickness epidermal acantholysis with superimposed spongiosis, hyperorthokeratosis and focal parakeratosis. Immunohistochemistry and quantitative confocal microscopy showed abnormal tissue distribution and reduced levels of expression for plakoglobin, desmoplakin and connexin 43 at epidermal junctional sites.Conclusions:  Interpretation of the changes in the context of the two mutations provides insight into the mechanism of clinical cell adhesion disease.
Selective Serotonin Reuptake Inhibitor-Induced Sexual Dysfunction
Authors: Corona Giovanni , Ricca Valdo , Bandini Elisa , Mannucci Edoardo , Lotti Francesco , Boddi Valentina , Rastrelli Giulia , Sforza Alessandra , Faravelli Carlo , Forti Gianni , Maggi Mario 
Published: March 2009

ABSTRACT

Introduction
Sexual dysfunctions are often present in subjects with mood disturbances; however. antidepressants can induce per se sexual dysfunctions.

Aim
To explore the relationship between the use of selective serotonin reuptake inhibitors (SSRIs), non-SSRIs antidepressants and benzodiazepines (BDZ), hormonal parameters, and reported sexual dysfunction (as assessed by the Structured Interview on Erectile Dysfunction [SIEDY]) in male subjects with comparable psychopathological symptoms (as assessed by the Middlesex Hospital Questionnaire [MHQ] a self-reported test for the screening of mental disorders in a non-psychiatric setting).

Methods
A consecutive series of 2,040 (mean age 51 ± 13 years) male patients with sexual dysfunction was studied.

Main Outcome Measures
Several hormonal and biochemical parameters were investigated, along with SIEDY and the MHQ.

Results
Higher prolactin was observed only in patients using SSRIs, whereas no other hormonal difference was found after adjustment for confounders. Use of SSRIs was associated with a twofold risk for patient hypoactive sexual desire and with a higher impairment of reported erectile function. However, no difference in penile blood flow was observed. A very high risk (sevenfold) for delayed ejaculation (DE) was observed in SSRI users. Interestingly, the association with the mild, but not severe, form of DE was observed also in subjects using non-SSRI antidepressants (3.35 [1.48–7.59]; P &lt; 0.005). Different life stressors and relational parameters were also associated with SSRI use. SSRI users reported less enjoyment with masturbation and decreased partner desire and climax. Conversely, a lack of significant association was observed among BDZ or non-SSRI antidepressant users and all the aforementioned life-stressors and relational parameters.

Conclusions
SSRIs can negatively affect all the steps of the male sexual response cycle (desire–arousal–excitement–orgasm). SSRI-associated sexual dysfunction has a deleterious effect on both auto- and couple-erotic performances. Conversely, other antidepressants and BDZ are less often associated with sexual impairment.
Parent Reactions to a School‐Based Body Mass Index Screening Program
Authors: Johnson Suzanne Bennett , Pilkington Lorri L. , Lamp Camilla , He Jianghua , Deeb Larry C. 
Published: March 2009

ABSTRACTBackground:  This study assessed parent reactions to school‐based body mass index (BMI) screening.Methods:  After a K‐8 BMI screening program, parents were sent a letter detailing their child’s BMI results. Approximately 50 parents were randomly selected for interview from each of 4 child weight–classification groups (overweight, at risk of overweight, normal weight, underweight) to assess parent recall of the letter, reactions to BMI screening, and actions taken in response to the child’s BMI results.Results:  Most parents found the BMI screening letter easy to read and had poor recall of numerical information (eg, the child’s BMI percentile) but good recall of the child’s weight classification (eg, normal weight or overweight). Most parents, and ethnic‐minority parents in particular, supported school‐based BMI screening. Parents of children whose weight was outside of the normal range were more likely to recall receiving the letter and talking to the child and the child’s doctor about it. Parents who recalled their child as being overweight were more likely to report changing the child’s diet and activity level. Most parents, and ethnic‐minority parents in particular, wanted their child to participate in an after‐school exercise program. An overweight condition in parents, but not children, was associated with an interest in family‐based cooking and exercise classes.Conclusions:  Most parents, and ethnic‐minority parents in particular, viewed school‐based BMI screening and after‐school exercise programs favorably. Parents reported taking action in response to a BMI result outside of the normal range. Parents who were overweight themselves were particularly interested in family cooking and exercise classes.
Development of new nuclear markers and characterization of single nucleotide polymorphisms in kelp gull (Larus dominicanus)
Authors: DE MENDONÇA DANTAS GISELE PIRES , GODINHO RAQUEL , MORGANTE JOÃO STENGHEL , FERRAND NUNO 
Published: March 2009

AbstractThe present study seeks to develop nuclear markers for the kelp gull (Larus dominicanus). We hereby report the characterization of 12 independent nuclear introns, where 104 single nucleotide polymorphisms (SNPs) in 8138 sequenced base pairs were observed. These SNP markers are the first to be designed for genotyping a gull species. The markers will provide useful tools for understanding which processes act or acted upon kelp gulls to cause their low genetic variability in mitochondrial DNA. In addition, these markers open a new opportunity for population genetic and evolutionary studies in the Laridae group.