bluuebunny/crossref_metadata_2025 huggingface dataset:
Impaired sleep quality and sleep duration in smokers—results from the German Multicenter Study on Nicotine Dependence
Authors: Cohrs Stefan , Rodenbeck Andrea , Riemann Dieter , Szagun Bertram , Jaehne Andreas , Brinkmeyer Jürgen , Gründer Gerhard , Wienker Thomas , Diaz‐Lacava Amalia , Mobascher Arian , Dahmen Norbert , Thuerauf Norbert , Kornhuber Johannes , Kiefer Falk , Gallinat Jürgen , Wagner Michael , Kunz Dieter , Grittner Ulrike , Winterer Georg
Published: August 2012

Cigarette smoking is a severe health burden being related to a number of chronic diseases. Frequently, smokers report about sleep problems. Sleep disturbance, in turn, has been demonstrated to be involved in the pathophysiology of several disorders related to smoking and may be relevant for the pathophysiology of nicotine dependence. Therefore, determining the frequency of sleep disturbance in otherwise healthy smokers and its association with degree of nicotine dependence is highly relevant. In a population‐based case‐control study, 1071 smokers and 1243 non‐smokers without lifetime Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Axis I disorder were investigated. Sleep quality (SQ) of participants was determined by the Pittsburgh Sleep Quality Index. As possible confounders, age, sex and level of education and income, as well as depressiveness, anxiety, attention deficit hyperactivity, alcohol drinking behaviour and perceived stress, were included into multiple regression analyses. Significantly more smokers than non‐smokers (28.1% versus 19.1%; P < 0.0001) demonstrated a disturbed global SQ. After controlling for the confounders, impaired scores in the component scores of sleep latency, sleep duration and global SQ were found significantly more often in smokers than non‐smokers. Consistently, higher degrees of nicotine dependence and intensity of smoking were associated with shorter sleep duration. This study demonstrates for the first time an elevated prevalence of sleep disturbance in smokers compared with non‐smokers in a population without lifetime history of psychiatric disorders even after controlling for potentially relevant risk factors. It appears likely that smoking is a behaviourally modifiable risk factor for the occurrence of impaired SQ and short sleep duration.
Factors influencing food choices of food‐allergic consumers: findings from focus groups
Authors: Sommer I. , MacKenzie H. , Venter C. , Dean T.
Published: August 2012

Background

Up to 35% of the population modify their diet for adverse reactions to food. This study described the food choice behaviour of diagnosed food‐allergic (DFA), self‐reported food‐allergic or intolerant (SFA) and nonfood‐allergic (NFA) consumers, and explored differences between them.

Methods

Six focus groups with adults (n = 44) were conducted. Data analysis was performed using thematic content analysis.

Results

Compared to NFA participants, DFA consumers were deprived of satisfaction and pleasure from foods, experienced difficulties finding safe foods and had to be organized with eating. SFA participants faced similar problems, but to a lesser degree; their food choices were strongly influenced by emotional factors or health awareness.

Conclusion

Food‐allergic consumers' food choices are influenced by a number of factors that differ to those of NFA consumers. It is therefore important to offer people with food allergies or intolerances advice that goes beyond how to avoid allergens.
A HLA‐A null allele (A*24:132N) with a stop codon in exon 3 generated by a point mutation
Authors: Zou H. ‐Y. , Jin S. ‐Z. , Li Z.
Published: August 2012

Exons 1–8 of HLA‐A*24:132N allele are identical to those of HLA‐A*24:02:01:01, except for one nucleotide change at nt 746 in exon 3 from C to A.
CCR5 gene polymorphism is a genetic risk factor for radiographic severity of rheumatoid arthritis
Authors: Han S. W. , Sa K. H. , Kim S. I. , Lee S. I. , Park Y. W. , Lee S. S. , Yoo W. H. , Soe J. S. , Nam E. J. , Lee J. , Park J. Y. , Kang Y. M.
Published: August 2012

The chemokine receptor [C–C chemokine receptor 5 (CCR5)] is expressed on diverse immune effecter cells and has been implicated in the pathogenesis of rheumatoid arthritis (RA). This study sought to determine whether single‐nucleotide polymorphisms (SNPs) in the CCR5 gene and their haplotypes were associated with susceptibility to and severity of RA. Three hundred fifty‐seven patients with RA and 383 healthy unrelated controls were recruited. Using a pyrosequencing assay, we examined four polymorphisms −1118 CTATins/del (rs10577983), 303 A>G (rs1799987), 927 C>T (rs1800024), and 4838 G>T (rs1800874) of the CCR5 gene, which were distributed over the promoter region as well as the 5′ and 3′ untranslated regions. No significant difference in the genotype, allele, and haplotype frequencies of the four selected SNPs was observed between RA patients and controls. CCR5 polymorphisms of −1118 CTATdel (P = 0.012; corrected P = 0.048) and 303 A>G (P = 0.012; corrected P = 0.048) showed a significant association with radiographic severity in a recessive model, and, as a result of multivariate logistic regression analysis, were found to be an independent predictor of radiographic severity. When we separated the erosion score from the total Sharp score, the statistical significance of CCR5 polymorphisms showed an increase; −1118 CTATins/del (P = 0.007; corrected P = 0.028) and 303 A>G (P = 0.007; corrected P = 0.028). Neither SNPs nor haplotypes of the CCR5 gene showed a significant association with joint space narrowing score. These results indicate that genetic polymorphisms of CCR5 are an independent risk factor for radiographic severity denoted by modified Sharp score, particularly joint erosion in RA.
Successful cord blood transplantation in a patient with malignant infantile osteopetrosis and hemophilia
Authors: Buchbinder David , Steward Colin G. , Puthenveetil Geetha , Nugent Diane , Hsieh Loan , Kirov Ivan , Neudorf Steven , Soni Amit
Published: August 2012

Buchbinder D, Steward CG, Puthenveetil G, Nugent D, Hsieh L, Kirov I, Neudorf S, Soni A. Successful cord blood transplantation in a patient with malignant infantile osteopetrosis and hemophilia.

Abstract:  MIOP is a congenital disorder of osteoclast differentiation or dysfunction. Inadequate bone resorption by osteoclasts results in a spectrum of complications including hypocalcemia, osteosclerosis, marrow failure, extramedullary hematopoiesis, hydrocephalus, visual deficits, and eventual mortality. Early diagnosis and timely HCT is a recommended treatment approach for select patients prior to the development of end‐organ damage. A comorbid bleeding disorder presents a unique challenge in the setting of MIOP and cord blood HCT given the additional risk factors for bleeding including delayed engraftment, a high risk of developing sinusoidal obstruction syndrome, and potential need for emergent invasive procedures. To our knowledge, this is the first report of a patient with an autosomal recessive form of MIOP who successfully underwent a cord blood HCT complicated by the presence of mild hemophilia A and HCT‐related complications including delayed engraftment, sinusoidal obstruction syndrome, and need for multiple invasive procedures (e.g., ventriculostomy, tracheostomy) without clinically significant bleeding. Given the underlying diagnosis of MIOP and need for HCT, the challenge of mitigating the significant risk of bleeding in a patient with a comorbid bleeding disorder is discussed.
Host–parasite coevolution induces selection for condition‐dependent sex
Authors: Mostowy R. , Engelstädter J.
Published: August 2012

Sex and recombination remain one of the biggest riddles of evolutionary biology. One of the most prominent hypotheses, the Red Queen Hypothesis, claims that sex has evolved as a means to efficiently create genotypes that are resistant against coevolving parasites. However, previous models of the Red Queen have assumed that all individuals are equally likely to engage in sexual reproduction, regardless of their infection status, an assumption that may not be true in reality. Here, we consider a population genetic model of a host population coevolving with a parasite population, where the parasites are haploid and the hosts either haploid or diploid. We assume that the probability to engage in sex may be different in infected and uninfected hosts and ascertain the success of different reproductive strategies with a modifier‐gene approach. Our model shows that in the large majority of the parameter space, infection‐dependent sex is more successful than infection‐independent sex. We identify at least two reasons for this: (i) an immediate short‐term advantage of breaking‐down gene combinations of unfit individuals and (ii) a selfish spread of the condition‐dependent modifiers, in analogy to the ‘abandon‐ship’ effect in single species. In diploids, these effects are often powerful enough to overcome the detrimental effects of segregation. These results raise the intriguing question of why infection‐induced sex is not more commonly observed in nature.
Outcome and management of invasive candidiasis following oesophageal perforation
Authors: Hoffmann Martin , Kujath Peter , Vogt Florian‐M. , Laubert Tilman , Limmer Stefan , Mulrooney Thomas , Bruch Hans‐Peter , Jungbluth Thomas , Schloericke Erik
Published: August 2012

The regular colonisation of the oesophagus with a Candida species can, after oesophageal perforation, result in a contamination of the mediastinum and the pleura with a Candida species. A patient cohort of 80 patients with oesophageal perforation between 1986 and 2010 was analysed retrospectively. The most common sources with positive results for Candida were mediastinal biopsies and broncho‐alveolar secretions. Candida species were detected in 30% of the patients. The mortality rate was 41% in patients with positive microbiology results for Candida, whereas it was 23% in the remaining patient cohort. This difference did not reach statistical significance (P = 0.124). Mortality associated with oesophageal perforation was attributed mainly to septic complications, such as mediastinitis and severe pneumonia. During the study period we observed a shift towards non‐albicans species that were less susceptible or resistant to fluconazole. In selected patients with risk factors as immunosuppression, granulocytopenia and long‐term intensive‐care treatment together with the finding of Candida, an antimycotic therapy should be started. A surgical approach offers the possibility to obtain deep tissue biopsies. The antimycotic therapy should start with an echinocandin, as the resistance to fluconazole is growing and to cover non‐albicans Candida species, too.
Interactions of Metabolism, Inflammation, and Reproductive Tract Health in the Postpartum Period in Dairy Cattle
Authors: LeBlanc SJ
Published: August 2012

Contents

This paper reviews recent data and concepts on the development of inflammation in the reproductive tract of dairy cows during the first 2 months after calving. The incidence of metritis is typically 10–20%, with 5–15% of cows having purulent vaginal discharge (PVD), 15–40% having cervicitis approximately 1 month after calving, and 10–30% having cytological endometritis between 1 and 2 months after calving. Endometritis, cervicitis and PVD are distinct conditions, each of which is associated with significantly increased time to pregnancy, and affected cows often have more than one of these conditions. Cumulatively, 35–50% of cows have at least one form of pathological reproductive tract inflammation between 3 and 7 weeks postpartum. It is hypothesized that reproductive tract disease represents a failure of the immune system to switch fast enough or far enough from the down‐regulated state necessary for maintenance of pregnancy to a heightened state of function for postpartum clearance of bacteria and tissue debris and then to a ‘quiet’ state 3–4 weeks later. There are numerous links between fat metabolism, inflammation and immune function, and changes in these precede reproductive tract disease by several weeks. An excessive pro‐inflammatory state early in the postpartum period appears to be a key feature of cows with endometritis approximately 1 month later. Generally, worse postpartum negative energy balance (NEB) is associated with more severe or prolonged uterine inflammation. Aspects of both mononuclear cell proliferation and neutrophil oxidative burst are commonly impaired, particularly in association with elevated non‐esterified fatty acid concentrations and to a lesser degree by ketosis. In summary, NEB contributes to immune dysfunction which in turn is a major component of reproductive tract inflammatory disease. The factors that initiate and sustain harmful inflammation of the reproductive tract are not yet well quantified.
Post‐mating Inflammatory Responses of the Uterus
Authors: Katila T
Published: August 2012

Contents

This review attempts to summarize the current knowledge on uterine inflammatory response after mating in horses, pigs and cattle. Post‐mating endometritis has been extensively studied in horses as it has been considered to cause infertility. The inflammation is known to occur also in cattle, but it has not been investigated to a similar extent. There are a number of publications about mechanisms of post‐mating uterine inflammation in pigs, which seem to resemble those in horses. The major focus of this review is the horse, but relevant literature is presented also on swine and cattle. Spermatozoa, seminal plasma and semen extenders play roles in the induction of inflammation. In addition, sperm numbers, concentration and viability, as well as the site of semen deposition may modulate the inflammatory response. Cytokines, polymorphonuclear leucocytes (PMN) and mononuclear cells represent the uterine inflammatory response to mating. Inflammation is the first line of defence against invasion and eliminates excess spermatozoa and bacteria. Semen deposition elicits a massive PMN invasion, followed by phagocytosis of sperm aided by the formation of neutrophil extracellular traps. Exposure of the female genital tract to semen is important also for endometrial receptivity and pre‐implantation embryo development. Seminal plasma (SP) and inflammation elicit transient immune tolerance to antigens present in semen. SP contains immune‐regulatory molecules that activate and control immune responses to antigens by stimulating expression of cytokines and growth factors and by initiating tissue remodelling. SP also regulates ovarian function. Effective elimination of excess sperm and inflammatory by‐products and subsequent rapid return of the endometrium to the normal state is a prerequisite for pregnancy. Uterine backflow, driven by myometrial contractions and requiring a patent cervix, is an important physical tool in uterine drainage.
Retrotransposon long interspersed nucleotide element‐1 (LINE‐1) is activated during salamander limb regeneration
Authors: Zhu Wei , Kuo Dwight , Nathanson Jason , Satoh Akira , Pao Gerald M. , Yeo Gene W. , Bryant Susan V. , Voss S. Randal , Gardiner David M. , Hunter Tony
Published: August 2012

Salamanders possess an extraordinary capacity for tissue and organ regeneration when compared to mammals. In our effort to characterize the unique transcriptional fingerprint emerging during the early phase of salamander limb regeneration, we identified transcriptional activation of some germline‐specific genes within the Mexican axolotl (Ambystoma mexicanum) that is indicative of cellular reprogramming of differentiated cells into a germline‐like state. In this work, we focus on one of these genes, the long interspersed nucleotide element‐1 (LINE‐1) retrotransposon, which is usually active in germ cells and silent in most of the somatic tissues in other organisms. LINE‐1 was found to be dramatically upregulated during regeneration. In addition, higher genomic LINE‐1 content was also detected in the limb regenerate when compared to that before amputation indicating that LINE‐1 retrotransposition is indeed active during regeneration. Active LINE‐1 retrotransposition has been suggested to have a potentially deleterious impact on genomic integrity. Silencing of activated LINE‐1 by small RNAs has been reported to be part of the machinery aiming to maintain genomic integrity. Indeed, we were able to identify putative LINE‐1‐related piRNAs in the limb blastema. Transposable element‐related piRNAs have been identified frequently in the germline in other organisms. Thus, we present here a scenario in which a unique germline‐like state is established during axolotl limb regeneration, and the re‐activation of LINE‐1 may serve as a marker for cellular dedifferentiation in the early‐stage of limb regeneration.
Mesendoderm specification depends on the function ofPou2, the class VPOU‐type transcription factor, during zebrafish embryogenesis
Authors: Khan Alam , Nakamoto Andrew , Tai Miyako , Saito Shinji , Nakayama Yukiko , Kawamura Akinori , Takeda Hiroyuki , Yamasu Kyo
Published: August 2012

Zebrafishpou2, encoding the class VPOUtranscription factor orthologous to mouseOct‐3/4, has been implicated in different aspects of development, such as dorsoventral patterning, endoderm formation, and brain regionalization, by analyzingpou2mutant embryos. In the present study, we first conducted overexpression ofpou2‐modified genes by mRNAinjection, and found thatpou2and its active form (vp‐pou2) augmented mesoderm formation and suppressed endoderm specification, whereas repressivepou2(en‐pou2) affected the formation of the mesoderm and endoderm in a different manner. To avoid complications that might arise from differentpou2functions during the course of development, we used a transgenic line harboring inducibleen‐pou2(HEP), which could function in a dominant‐negative manner. We found that suppressing endogenouspou2byHEPinduction at the mid‐blastula stage enhanced endoderm development at the expense of mesoderm, whereas the same treatment in the late blastulae promoted mesoderm formation and suppressed the endoderm specification. Further analyses usingHEPinduction revealed that, from late epiboly to early somitogenesis,pou2regulated additional developmental aspects, such as brain regionalization, heart development, and tail formation. Our findings suggest thatPou2 functions in multiple aspects of vertebrate development, especially in the binary decision of the mesendoderm to mesoderm and endoderm in different ways depending on the developmental stage.
Remote frozen section examination of breast sentinel lymph nodes by telepathology
Authors: Gifford Andrew J. , Colebatch Andrew J. , Litkouhi Shahram , Hersch Fred , Warzecha William , Snook Kylie , Sywak Mark , Gill Anthony J.
Published: August 2012

Background

Intraoperative sentinel lymph node (SLN) examination during breast cancer surgery guides the need for immediate axillary clearance. This may be difficult to implement when surgery is performed distant to the centres where pathological examination is undertaken. We aimed to implement and validate a telepathology service for the remote examination of breast SLN by frozen section (FS).

Methods

We tested an Internet‐based remote microscopy system to report intraoperative FS in real time from two district hospitals without on‐site anatomical pathology services.

Results

FS was performed remotely on 52 patients. Seventeen out of 52 patients had metastases, of which there were six false‐negative diagnoses comprising four of micrometastatic disease and two of isolated tumour cells (ITCs). There were no false‐negative diagnoses for macrometastatic disease and no false‐positive diagnoses. As a control, we audited our experience with 239 consecutive SLN FS examined by on‐site pathologists. Sixty out of 239 patients had metastases, of which there were 24 false‐negative diagnoses comprising 12 cases of ITC, 5 of micrometastases and 7 of macrometastases. The accuracy of remote FS was equivalent to that of in‐house FS (88.2% versus 89.9%).

Conclusion

Remote FS for breast SLN is an accurate procedure ,which is not inferior to FS performed on site.
Phylogenetic host specificity and understanding parasite sharing in primates
Authors: Cooper Natalie , Griffin Randi , Franz Mathias , Omotayo Moshood , Nunn Charles L.
Published: August 2012

Understanding how parasites are transmitted to new species is of great importance for human health, agriculture and conservation. However, it is still unclear why some parasites are shared by many species, while others have only one host. Using a new measure of ‘phylogenetic host specificity’, we find that most primate parasites with more than one host are phylogenetic generalists, infecting less closely related primates than expected. Evolutionary models suggest that phylogenetic host generalism is driven by a mixture of host–parasite cospeciation and lower rates of parasite extinction. We also show that phylogenetic relatedness is important in most analyses, but fails to fully explain patterns of parasite sharing among primates. Host ecology and geographical distribution emerged as key additional factors that influence contacts among hosts to facilitate sharing. Greater understanding of these factors is therefore crucial to improve our ability to predict future infectious disease risks.
Herbicides in the environment alter infection dynamics in a microbial host–parasite system
Authors: Van den Wyngaert Silke , Gsell Alena S. , Spaak Piet , Ibelings Bas W.
Published: August 2012

Parasites play an important role in the regulation of host population growth. How these ubiquitous stressors interact with anthropogenic stressors is less often studied. In a full factorial experiment we explored the independent and combined effects of the widely used herbicide diuron and a chytrid parasite on the fitness of genetically different monoclonal diatom populations. Furthermore, we evaluated how herbicide exposure influenced infection dynamics, parasite fitness and the impact of infectious disease on host populations. We found no evidence of host genetic variation for diuron sensitivity and parasite resistance. Instead, host population phenotype was a decisive factor in controlling parasite growth. Although herbicide exposure initially posed a constraint on disease transmission, it enhanced the spread of disease over time. Consequently, the nature of the parasite–toxicant stressor interaction shifted from antagonistic (on exponential host growth) towards additive (on final uninfected host density). We conclude that herbicide exposure can modify infection dynamics and impact of disease on host populations through the complex interplay between host and parasite growth dynamics and host population phenotype.
PEASANTS AGAINST PRIVATE PROPERTY RIGHTS: A REVIEW OF THE LITERATURE
Authors: Vendryes Thomas
Published: August 2012

Land is the main – if not the only – asset for a majority of people in developing countries. The definition and allocation of rights over land are thus naturally essential aspects of individuals’ daily lives, as well as critical determinants of social and economic development. The privatization of land rights has long been seen as a necessary process, enhancing both efficiency and equity. However, privatized land rights have not always emerged endogenously, while exogenously driven programs of land privatization have not always been successful nor popular. This has raised questions about the expected benefits of land rights privatization. This paper aims at summarizing the main arguments and studies, both theoretical and empirical, on this issue, with a specific focus on the factors that can make privatization inefficient or detrimental for the most concerned individuals.
Boarding the Aircraft: Trust Development Amongst Negotiators of a Complex Merger
Authors: Lander Michel W. , Kooning Linda
Published: August 2012

We explore trust development in the context of an international merger negotiation. Based on in‐depth interviews with chief negotiators of the Air France–KLM merger, we contribute to existing theory by showing that trust develops in three interrelated domains: personal, process, and outcome. Progressively, trust develops in all domains on the basis of antecedents that differ between phases and domains. Distinguishing between different domains facilitates analysis of trust asymmetry and the coexistence of trust and distrust, as well as the influence of trust in interorganizational relationships.
Altered leaf colour is associated with increased superoxide‐scavenging activity in aureusidin‐producing transgenic plants
Authors: Shakya Roshani , Ye Jingsong , Rommens Caius M.
Published: August 2012

The health‐promoting property of diets rich in fruits and vegetables is based, in part, on the additive and synergistic effects of multiple antioxidants. In an attempt to further enhance food quality, we introduced into crops the capability to synthesize a yellow antioxidant, aureusidin, that is normally produced only by some ornamental plants. For this purpose, the snapdragon (Antirrhinum majus) chalcone 4′‐O‐glucosyltransferase (Am4’CGT) and aureusidin synthase (AmAs1) genes, which catalyse the synthesis of aureusidin from chalcone, were expressed in tobacco (Nicotiana tabacum) and lettuce (Lactuca sativa) plants that displayed a functionally active chalcone/flavanone biosynthetic pathway. Leaves of the resulting transgenic plants developed a yellow hue and displayed higher superoxide dismutase (SOD) inhibiting and oxygen radical absorbance capacity (ORAC) activities than control leaves. Our results suggest that the nutritional qualities of leafy vegetables can be enhanced through the introduction of aurone biosynthetic pathways.
Why (and how) do teachers engage in social networks? An exploratory study of professional use of Facebook and its implications for lifelong learning
Authors: Ranieri Maria , Manca Stefania , Fini Antonio
Published: August 2012

To date, little empirical research on professional use of social network sites has been conducted, particularly with reference to groups of teachers on Facebook. The paper presents the results of two surveys addressed to the founders of five Italian Facebook groups and their members (n = 1107), with the aim of investigating mechanisms underlying group membership and reflecting on their implications for professional development. A number of hypotheses were tested in order to explore the nature of three dimensions (domain, network and practice) involved in these groups, assimilated by authors into networks of practice. The study investigated the mechanisms of group membership and their participatory dynamics in terms of group types (generic vs. thematic), duration of membership and the interplay between offline and online activities. Results showed that groups differing in terms of domain (generic or thematic) are characterized by particular mechanisms of affiliation and participation and that mechanisms of legitimation of the members, as well as of shared resources, are associated with the duration of membership. Further research should be conducted to investigate how social capital dynamics evolve over time, influencing the construction of group identity.

Practitioner Notes

What is already known about this topic

The use of social network sites (SNS), particularly Facebook, is growing in the educational field.

To date, little attention has been given to the use of Facebook for professional development.

Empirical research mainly refers to the higher education context and shows that the use of SNS has positive outcomes for social capital.

What this paper adds

An application of social capital theory with the networks of practice framework (Brown & Duguid, ) to the study of professional groups of teachers in SNS.

An understanding of groups in terms of shared social capital, both bridging and bonding.

An analysis of the interplay between online and offline activities in terms of professional benefits for teachers.

Implications for practice and/or policy

Participation in this kind of groups may have a positive impact on professional development.

Social networks may afford different types of social capital for professionals.

Policy makers should encourage and support the use of social networks for professional learning.
Tweeting for learning: A critical analysis of research on microblogging in education published in 2008–2011
Authors: Gao Fei , Luo Tian , Zhang Ke
Published: August 2012

This study critically analyzed the current body of published research on microblogging in education (MIE) to build a deep and comprehensive understanding of this increasingly popular phenomenon. Twenty‐one studies on MIE in 2008–2011 were selected based on the selection criteria and analyzed to answer the following questions: What types of research have been published on MIE? How was microblogging used for teaching and learning in these studies? What educational benefits did microblogging have on teaching and learning? What suggestions and implications did the current research have for future MIE research and practices? The analysis suggests that microblogging has a potential to encourage participation, engagement, reflective thinking as well as collaborative learning under different learning settings. The quality of research, however, varies greatly, suggesting a need for rigorous research on MIE. The analysis has implications for MIE practices as well as research and development efforts.

Practitioner Notes

What is already known about this topic

Microblogging has a potential to facilitate learning.

Research on microblogging has been conducted under different educational settings.

What this paper adds

What are the characteristics of the current research on microblogging in education.

How educators and researchers integrated microblogging to achieve different educational goals as identified in these studies.

What are the identified educational effects of using microblogging for teaching and learning.

What are the challenges and suggestions of using microblogging in teaching and learning.

Implications for practice and/or policy

Future research on microblogging in education should go beyond formal higher education settings by considering learning occurring in other settings.

Future research needs to observe and analyze how learners participate and learn in microblogging‐based environments over time.

Innovative data collection and analysis methods are needed to understand the interaction and learning that occur in such environments.

Future research is needed to identify effective approaches of microblogging integration.
Parent–Child Shared Time From Middle Childhood to Late Adolescence: Developmental Course and Adjustment Correlates
Authors: Lam Chun Bun , McHale Susan M. , Crouter Ann C.
Published: August 2012

The development and adjustment correlates of parent–child social (parent, child, and others present) and dyadic time (only parent and child present) from age 8 to 18 were examined. Mothers, fathers, and firstborns and secondborns from 188 White families participated in both home and nightly phone interviews. Social time declined across adolescence, but dyadic time with mothers and fathers peaked in early and middle adolescence, respectively. In addition, secondborns’ social time declined more slowly than firstborns’, and gendered time use patterns were more pronounced in boys and in opposite‐sex sibling dyads. Finally, youths who spent more dyadic time with their fathers, on average, had higher general self‐worth, and changes in social time with fathers were positively linked to changes in social competence.
Differential Migration Prospects, Skill Formation, and Welfare
Authors: Stark Oded , Zakharenko Roman
Published: August 2012

This paper develops a one sector, two‐input model with endogenous human capital formation. The two inputs are two types of skilled labor: “engineering,” which exerts a positive externality on total factor productivity, and “law,” which does not. The paper shows that a marginal prospect of migration by engineers increases human capital accumulation of both types of workers (engineers and lawyers), and also the number of engineers who remain in the country. These two effects are socially desirable, since they move the economy from the (inefficient) free‐market equilibrium towards the social optimum. The paper also shows that if the externality effect of engineering is sufficiently powerful, everyone will be better off as a consequence of the said prospect of migration, including the engineers who lose the migration “lottery,” and even the individuals who practice law.
Reverse Causality in Global and Intra‐European Imbalances
Authors: Schnabl Gunther , Freitag Stephan
Published: August 2012

The paper discusses global current account imbalances in the context of an asymmetric world monetary system. It identifies the USA and Germany as center countries with rising/high current account deficits (USA) and surpluses (Germany). These are matched by current account surpluses of countries stabilizing their exchange rates against the dollar (dollar periphery) and current account deficits of countries stabilizing their exchange rates against the euro or members of the euro area (euro periphery). The paper finds that changes of world current account positions are closely linked to the monetary policy decision patterns both in the centers and peripheries. Whereas in the centers current account positions are affected by monetary policies, in the peripheries exchange rate stabilization cum sterilization matters. In specific, monetary expansion in the USA as well as exchange rate stabilization and sterilization policies in the dollar periphery are found to have contributed to global imbalances.
Bi‐currency versus Single‐currency Targeting: Lessons from the Russian Experience
Authors: Sokolov Vladimir
Published: August 2012

This paper examines how the 2005 shift in Russian exchange rate policy from US dollar (USD) single‐currency to USD–EUR (euro) bi‐currency targeting has impacted domestic interest rates. The finding show that this policy shift has disconnected Russian interest rates from US dollar‐denominated interest rates, while instead linking them to a synthetic interest rate composed of USD and EUR rates at the same proportion as that of these two currencies in the currency basket against which the ruble's exchange rate is set. The Russian experience shows that while the adoption of bi‐currency targeting may help ensure that domestic interest rates are less dependent on the monetary cycle of a single country, these rates are instead likely to reflect financial developments in all countries whose currencies are included in the currency basket. This insight is likely to be relevant for other countries that pursue basket‐targeting policies.
The Coexistence of High Unemployment and Good Economic Performance in Large Open Developing Countries
Authors: Wang Ming‐cheng , Fang Chen‐ray , Huang Li‐hsuan
Published: August 2012

The Harris–Todaro labor reallocation mechanism is embedded into a North–South trade model and a theoretical model is provided to explain the coexistence of high unemployment and good economic performance as large developing countries become more open to trade. The relative improvement in the total factor productivity of the Southern manufacturing sector is conjectured to give rise to this phenomenon. Although it induces an increase in the demand for labor in the Southern urban areas, this increase in demand is outweighed by an increase in supply brought by the reallocation of labor from rural to urban areas. The final result is higher unemployment. The model is supported by some empirical evidence.
Advertising Subsidy and International Oligopolistic Competition
Authors: Ma Jie , Ulph Alistair M.
Published: August 2012

This paper examines the strategic role of advertising subsidies in a third‐country trade model in which two firms located in different countries export their products to a third country. First a basic model of advertising in oligopolistic industries is developed in which firms decide how much to invest in either predatory or cooperative advertising and then engage in product market competition either as Cournot competitors or as Bertrand competitors. It is shown that firms invest in only one form of advertising; which form they invest in depends on the relative effectiveness of the two types of advertising, the degree of product differentiation, and the form of product market competition. The paper then studies strategic industrial policy and shows that an advertising subsidy is the optimal strategic policy irrespective of the form of product market competition and the form of advertising in which firms invest.
Outsourcing: Volume and Composition of R&D
Authors: Beladi Hamid , Marjit Sugata , Yang Lei
Published: August 2012

This paper examines the impact of the outsourcing of production on the volume and composition of the home country's research and development (R&D). We find that outsourcing decreases the process R&D of the multinational firm in large markets when it only conducts process R&D (the substitution effect between outsourcing and process R&D). Outsourcing tends to emerge as a complementary factor to product development when the multinational firm conducts both product R&D and process R&D (the complementary effect between outsourcing and product R&D) under some conditions. This implies that international outsourcing has a different effect on product innovation and process innovation.
Economies of Scope and Patterns of Global Outsourcing
Authors: Yu Zhihao
Published: August 2012

This paper develops a model with two Salop circles representing the product space of the intermediate input suppliers and the final‐good producers. First, it is shown that economies of scope in production are the necessary condition for outsourcing. Second, the propensity to outsource exhibits a U‐shape relationship depending on an intricate combination of the degree of economies of scope and product differentiation of the intermediate input suppliers. Third, an improvement of production technology can have ambiguous effects on the propensity to outsource.
HINDUISM AND SCIENCE: SOME REFLECTIONS
Authors: Raman Varadaraja V.
Published: August 2012

Abstract In recent decades scholars in every major religious tradition have been commenting on the relationship between their own tradition and science. The subject in the context of Hinduism is complex because there is no central institutionalized authority to dictate what is acceptable Hindu belief and what is not. This has resulted in a variety of perspectives that are touched upon here. Historical factors in the introduction of modern science in the Hindu world have also influenced the subject. The reflections in this paper are based on these.
The role of oral language skills in reading and listening comprehension of text: a comparison of monolingual (L1) and bilingual (L2) speakers of English language
Authors: Babayiğit Selma
Published: August 2012

The study examined the role of oral language skills in reading comprehension and listening comprehension levels of 125 monolingual (L1) and bilingual (L2) English‐speaking learners (M = 121.5 months, SD = 4.65) in England. All testing was conducted in English. The L1 learners outperformed their L2 peers on the measures of oral language and text comprehension, but the two groups performed at comparable levels on word‐reading accuracy and speed. Oral language, indexed by vocabulary and morphosyntactic skills, emerged as the most powerful unique predictor of both reading and listening comprehension levels. Although there was a tendency of oral language to be more strongly related to L2 reading comprehension, its relationship with listening comprehension was comparable across the two language groups. Finally, individual differences in oral language skills emerged as the primary factor that explained the language group differences in text comprehension levels. Educational implications of these findings were discussed.
FINANCIAL CRISIS, RISK PERCEPTION AND THE IMPLIED VOLATILITY TRANSMISSION: A CROSS‐REGION STUDY*
Authors: GANG JIANHUA , YE NAN , ZHANG CHENGSI
Published: August 2012

This study uses the newly released Hang Seng Volatility Index (VHSI) data set to explore differences of the risk perception between the US and Hong Kong (HK) financial markets as well as the direct sentiment spillover effects across the regions. Results show no fear or exuberance in HK market while significant fear in the USA when the market closes losses two days in a row. Cross‐market evidence indicates the existence of fear in the HK market is completely imported from the USA. Direct implied volatility flows one way from USA to HK at first but shows reversal after the financial crisis.
FINANCIAL CRISIS AND QUANTITATIVE EASING: CAN BROAD MONEY TELL US ANYTHING?*
Authors: COBHAM DAVID , KANG YUE
Published: August 2012

When the Bank of England introduced quantitative easing (QE) it emphasised effects on money and credit, but much of its empirical research has focused on effects on long‐term interest rates. We use the flow of funds to analyse the implications of QE for broad money, and argue that the financial crisis, fiscal expansion and QE may have constituted major exogenous shocks to money. Regressions in which the growth of nominal spending depends on the growth of nominal money and other variables suggest that money has had a much larger role in the period of the crisis and QE.
Contingency in ecosystem but not plant community response to multiple global change factors
Authors: Bradford Mark A. , Wood Stephen A. , Maestre Fernando T. , Reynolds James F. , Warren Robert J.
Published: August 2012

Community and ecosystem responses to global environmental change are contingent on the magnitude of change and interacting global change factors. To reveal whether responses are also contingent on the magnitude of each interacting factor, multifactor, multilevel experiments are required, but are rarely conducted.

We exposed model grassland ecosystems to six levels of atmospheric CO2 and six levels of nitrogen enrichment, applying the latter both chronically (simulating deposition) and acutely (simulating fertilization). The 66 treatments were maintained for 6 months under controlled growing conditions, with biomass harvested every 28 d and sorted to species.

Aboveground plant productivity responses to CO2 were contingent on nitrogen amount, and the responses to nitrogen amount were dependent on whether applications were chronic or acute. Specifically, productivity responses to increasing CO2 concentrations were accentuated with higher nitrogen enrichments, and productivity was greater when higher nitrogen enrichments were applied acutely. Plant community composition was influenced only by nitrogen enrichment, where the co‐dominant grass species with the greatest leaf trait plasticity increasingly dominated with higher nitrogen amounts.

Community processes are considered to be unpredictable, but our data suggest that the prediction of the impacts of simultaneous global changes is more complex for ecosystem processes, given that their responses are contingent on the levels of interacting factors.
Coming of leaf age: control of growth by hydraulics and metabolics during leaf ontogeny
Authors: Pantin Florent , Simonneau Thierry , Muller Bertrand
Published: August 2012

Leaf growth is the central process facilitating energy capture and plant performance. This is also one of the most sensitive processes to a wide range of abiotic stresses. Because hydraulics and metabolics are two major determinants of expansive growth (volumetric increase) and structural growth (dry matter increase), we review the interaction nodes between water and carbon. We detail the crosstalks between water and carbon transports, including the dual role of stomata and aquaporins in regulating water and carbon fluxes, the coupling between phloem and xylem, the interactions between leaf water relations and photosynthetic capacity, the links between Lockhart's hydromechanical model and carbon metabolism, and the central regulatory role of abscisic acid. Then, we argue that during leaf ontogeny, these interactions change dramatically because of uncoupled modifications between several anatomical and physiological features of the leaf. We conclude that the control of leaf growth switches from a metabolic to a hydromechanical limitation during the course of leaf ontogeny. Finally, we illustrate how taking leaf ontogeny into account provides insights into the mechanisms underlying leaf growth responses to abiotic stresses that affect water and carbon relations, such as elevated CO2, low light, high temperature and drought.

Contents

Summary
349

I.
Leaf growth: volume, structures, water and carbon
349

II.
Coupling water and carbon limitations through the Lockhart model?
350

III.
ABA signalling pathway as a hub to coordinate water and carbon relations
353

IV.
Leaf venation: just a two‐way pipe network?
354

V.
Leaf ontogeny orchestrates the actors involved in the control of leaf growth
355

VI.
The growing leaf in a changing world
360

VII.
Conclusion
361

Acknowledgements
362

References
362
Indole derivative production by the root endophyte Piriformospora indica is not required for growth promotion but for biotrophic colonization of barley roots
Authors: Hilbert Magdalena , Voll Lars M. , Ding Yi , Hofmann Jörg , Sharma Monica , Zuccaro Alga
Published: August 2012

Beneficial effects elicited by the root endophyte Piriformospora indica are widely known, but the mechanism by which these are achieved is still unclear. It is proposed that phytohormones produced by the fungal symbiont play a crucial role in the interaction with the plant roots.

Biochemical analyses of the underlying biosynthetic pathways for auxin production have shown that, on tryptophan feeding, P. indica can produce the phytohormones indole‐3‐acetic acid (IAA) and indole‐3‐lactate (ILA) through the intermediate indole‐3‐pyruvic acid (IPA). Time course transcriptional analyses after exposure to tryptophan designated the piTam1 gene as a key player. A green fluorescence protein (GFP) reporter study and transcriptional analysis of colonized barley roots showed that piTam1 is induced during the biotrophic phase.

Piriformospora indica strains in which the piTam1 gene was silenced via an RNA interference (RNAi) approach were compromised in IAA and ILA production and displayed reduced colonization of barley (Hordeum vulgare) roots in the biotrophic phase, but the elicitation of growth promotion was not affected compared with the wild‐type situation.

Our results suggest that IAA is involved in the establishment of biotrophy in P. indica–barley symbiosis and might represent a compatibility factor in this system.