bluuebunny/crossref_metadata_2025 huggingface dataset:
Incentive Compensation and the Likelihood of Termination: Theory and Evidence from Real Estate Organizations
Authors: Hallman Greg , Hartzell Jay C. , Parsons Christopher A.
Published: March 2011

We analyze two managerial compensation incentive devices: the threat of termination and pay for performance. We first develop a simple model predicting that these devices are substitutes: when termination incentives are low, optimal contracts provide stronger pay‐for‐performance incentives. We then use data from real estate organizations to provide two independent tests of the model’s central prediction. First, we use the fact that chief executive officers of Real Estate Investment Trusts (REITs) and general partners of Real Estate Limited Partnerships (RELPs) perform similar tasks, yet organizational features of RELPs ensure that the latter are much harder to terminate. Consistent with the model, we find that pay‐for‐performance sensitivity is much higher for general partners of RELPs, where the termination threat is less credible. Second, we use a recent cross‐section of REITs to show that in property types where it is expected to be more costly to replace managers, those managers have stronger pay‐for‐performance incentives.
Performance of Pairs Trading Strategy in the U.S. REIT Market
Authors: Mori Masaki , Ziobrowski Alan J.
Published: March 2011

We examine the performance of pairs trading in the U.S. REIT market compared with that in the U.S. general stock market over the period 1987 to 2008. The results suggest that the REIT market provided superior profit opportunities for this strategy over common stocks after accounting for the effect of the bid‐ask bounce between 1993 and 2000. This was likely because of the unique characteristics of REITs, which permitted the selection of good pairs of close substitutes and the structural changes that occurred in 1993 in the REIT market. The superior trading profits in REITs disappear after 2000.
Can Fund Managers Select Outperforming REITs? Examining Fund Holdings and Trades
Authors: Cici Gjergji , Corgel Jack , Gibson Scott
Published: March 2011

Despite at least six empirical studies published since 2000 designed to assess fund managers’ Real Estate Investment Trust (REIT)‐selection ability, their skill remains in question. Unlike previous studies, we examine fund holdings and trades of REITs to answer this question. This approach allows us to explicitly account for portfolio rebalancing that alters REIT‐characteristic weights of fund portfolios. Results show that fund managers, after controlling for property type, size and momentum, generated significant positive alpha with their securities‐selection ability. To understand the sources of such ability, we examine whether fund managers who followed certain trading strategies outperformed relative to other managers. The potential trading strategies are based on public information related to geographic concentration, net‐asset‐value‐to‐price ratios, income and appreciation styles and leverage of the underlying REITs. Comparative and regression analyses show that none of the strategies fully explains why fund managers were able to select REITs that outperformed. We surmise that the outperformance mainly derives from the endemic abilities of managers to uniquely process REIT‐specific information and generate private valuation beliefs that lead to profitable investment decisions.
Resource Mobilization in International Social Entrepreneurship: Bricolage as a Mechanism of Institutional Transformation
Authors: Desa Geoffrey
Published: March 2011

International entrepreneurs are often confronted with unfavorable normative, regulatory, and cognitive institutional environments. Those entrepreneurial firms that successfully navigate this uneven terrain appear to defy institutional constraint and create economic growth. Yet little is known about how ventures develop in unfavorable institutional environments, particularly in terms of social entrepreneurship. Contrary to the predominant view of resource mobilization, this article finds that social entrepreneurs confronted with institutional constraints engage in bricolage to reconfigure existing resources at hand. In the process, bricolage can act as a legitimating mechanism for institutional change. This article examines how regulatory, political, and technological institutions affect resource–mobilization in 202 technology social ventures from 45 countries. The implications for social entrepreneurship and for institutionally embedded entrepreneurial action are discussed.
Analyzing the Influence of Gender upon High–Technology Venturing within the Context of Business Incubation
Authors: Marlow Susan , McAdam Maura
Published: March 2011

We explore the influence of sex role attribution and associated gendered ascriptions upon the entrepreneurial experiences of a female high–technology business owner operating within the context of business incubation. Our literature analysis and empirical evidence suggest that stereotypical gendered expectations surrounding incubated high–technology venturing reproduce masculine norms of entrepreneurial behavior. The adoption of a gendered perspective to explore the experience of business incubation responds to contemporary calls to embed feminist analyses within the entrepreneurial field of enquiry. Furthermore, we draw upon evidence from a detailed case study informed by a life history narrative to explore a female entrepreneur's experience of incubated high–technology entrepreneurship.
Is Age a Determinant of SMEs’ Financing Decisions? Empirical Evidence Using Panel Data Models
Authors: Serrasqueiro Zélia , Nunes Paulo Maçãs
Published: March 2011

Using panel data models, this study investigates whether firm's age is a determinant of Portuguese SMEs’ financing decisions. The results suggest that age is relevant for: the impact of financial deficit on variations of short– and long–term debt; the level of adjustment of short– and long–term debt toward the respective optimal levels; and the relationships between usual determinants and short– and long–term debt. The results for young and old SMEs suggest that Trade–Off Theory and Pecking Order Theory should not be considered to be mutually exclusive, since both theories are necessary to understand the SMEs’ capital structure decisions throughout their life–cycle.
Corporate Entrepreneurship and Innovation in Silicon Valley: The Case of Google, Inc.
Authors: Finkle Todd A.
Published: March 2011

In May 2009, Sergey Brin and Larry Page, co–founders of Google, Inc., were trying to determine how they were going to navigate Google through the worst recession since the Great Depression. Their primary problem was how to maintain the company's culture of corporate entrepreneurship and innovation in the face of stagnant profits and a host of other issues. Google sought answers on how to increase corporate entrepreneurship and innovation during the worst economic environment that the company had ever experienced.
Conflicts of Interest in Human Subjects Research: Special Considerations for Academic Emergency Physicians
Authors: Asher Shellie L. , Schears Raquel M. , Miller Chadwick D.
Published: March 2011

ACADEMIC EMERGENCY MEDICINE 2011; 18:292–296 © 2011 by the Society for Academic Emergency Medicine

Trust in the doctor–patient or investigator–subject relationship is vital to the practice of medicine and advancement through biomedical research. Individual and environmental factors can make this trust more difficult to establish in the emergency department (ED). To perform research ethically and maintain this trust, it is important to minimize and manage conflicts of interest in human subjects research. While principle‐based ethics are an important starting point, the virtue of the individual investigator is required to assure that the interests and safety of research participants are prioritized over the interests of the investigator or the medical community at large. SAEM Ethics Committee 2009–2010 Objective 4: “Based on the results of the didactic session presented at the annual meeting, develop a guide to assist SAEM members in the recognition of potential conflicts of interest in the practice of academic emergency medicine”.

ACADEMIC EMERGENCY MEDICINE 2011; 18:1–5 © 2011 by the Society for Academic Emergency Medicine
Effects of resistance training on endurance capacity and muscle fiber composition in young top‐level cyclists
Authors: Aagaard P. , Andersen J. L. , Bennekou M. , Larsson B. , Olesen J. L. , Crameri R. , Magnusson S. P. , Kjær M.
Published: March 2011

Equivocal findings exist on the effect of concurrent strength (S) and endurance (E) training on endurance performance and muscle morphology. Further, the influence of concurrent SE training on muscle fiber‐type composition, vascularization and endurance capacity remains unknown in top‐level endurance athletes. The present study examined the effect of 16 weeks of concurrent SE training on maximal muscle strength (MVC), contractile rate of force development (RFD), muscle fiber morphology and composition, capillarization, aerobic power (VO2max), cycling economy (CE) and long/short‐term endurance capacity in young elite competitive cyclists (n=14). MVC and RFD increased 12–20% with SE (P<0.01) but not E. VO2max remained unchanged. CE improved in E to reach values seen in SE. Short‐term (5‐min) endurance performance increased (3–4%) after SE and E (P<0.05), whereas 45‐min endurance capacity increased (8%) with SE only (P<0.05). Type IIA fiber proportions increased and type IIX proportions decreased after SE training (P<0.05) with no change in E. Muscle fiber area and capillarization remained unchanged. In conclusion, concurrent strength/endurance training in young elite competitive cyclists led to an improved 45‐min time‐trial endurance capacity that was accompanied by an increased proportion of type IIA muscle fibers and gains in MVC and RFD, while capillarization remained unaffected.
Effects of resistance training on matrix metalloproteinase‐2 activity and biomechanical and physical properties of bone in ovariectomized and intact rats
Authors: Shiguemoto G. E. , Prestes J. , Leite R. D. , Pereira G. B. , Pontes C. L. S. , D'Ávila F. V. , Botero J. P. , Baldissera V. , Nonaka K. O. , Selistre‐de‐Araújo H. S. , Perez S. E. A.
Published: March 2011

The purpose of this study was to investigate the influence of resistance training on the activity of matrix metalloproteinase (MMP)‐2 and bone biomechanical properties in ovariectomized and intact rats. Forty‐eight female rats were divided into two distinct groups, ovariectomized (OVX) and intact (Int), which were subdivided into three similar subgroups: sedentary, acute exercise and chronic exercise. Rats performed a resistance training for 12 weeks in which animals climbed a vertical ladder of 1.1 m with weights attached to their tails. Sessions were performed with an interval of 3, 4–9 and 8–12 days scaled dynamic movements of climbing. Biomechanical and physical analyses were performed using a universal testing machine, and MMP‐2 activity analysis by zymography. Bone density (BD), mineral density (MD), maximum load and fracture load was reduced in sedentary and acute exercise OVX groups compared with the sedentary intact group (P<0.05); in contrast, chronically trained groups (OVX and Int) showed a significant increase in BD, MD and fracture load compared with all the other groups. MMP‐2 activity in chronically trained groups also showed a significant increase, while the sedentary OVX group showed a decrease in MMP‐2 activity compared with the intact sedentary group (P<0.05). Our results suggest that the resistance training proposed in our work was efficient in reverting the deleterious effects of ovariectomy on bone tissue, and also produced modeling effects in intact rats. On the other hand, ovariectomy reduced the activity of MMP‐2 and produced deleterious effects on bone tissue, mimicking menopause intrinsically.
Essential fatty acid status in teenage girls with eating disorders and weight loss
Authors: Swenne I , Rosling A , Tengblad S , Vessby B
Published: March 2011

Aim:  To explore the relationship between essential fatty acids (FA) and weight changes in adolescent girls with eating disorders (ED).

Methods:  Blood samples were obtained from 220 girls with ED and 39 healthy controls. The girls with ED were 15.3 ± 1.5 years of age and weighed 49.8 ± 8.7 kg (BMI 18.3 ± 2.8 kg/m2) after a weight loss of 6.8 ± 6.4 kg. FA were analysed in plasma phospholipids (PPL) and erythrocyte membranes (ERY).

Results:  The proportions of saturated and monounsaturated FA were increased during weight loss, while linoleic acid (18:2ω6) was decreased. The proportions of eicosapentanoic acid (EPA) (20:5ω3) and docosahexanoic acid (DHA) (22:6ω3) in PPL and ERY did not differ from controls. The activity of stearoyl‐CoA‐desaturase was increased as evidenced by an increased product/precursor ratio and correlated with the rate of weight loss. The activities of delta‐6‐desaturase and delta‐5‐desaturase did not differ from controls. The rate of weight loss was inversely correlated with delta‐6‐desaturase and directly correlated with delta‐5‐desaturase.

Conclusion:  The FA profile indicates low‐fat intake, fat mobilization from stores and an increased conversion of essential FA at the delta‐5‐desaturase step during weight loss in adolescent girls with ED. Normal levels of EPA and DHA were maintained.
Development of smooth pursuit eye movements in very prematurely born infants: 2. The low‐risk subgroup
Authors: Grönqvist Helena , Brodd Katarina Strand , Rosander Kerstin
Published: March 2011

Aim:  To investigate the impact of premature birth on visual tracking in a group of 37 infants, born before the 32nd gestational weeks (mean 29 + 6 weeks) and diagnosed as being without major neonatal complications. This paper is a part of the LOVIS study (Strand Brodd, Ewald, Grönqvist, Holmström, Strömberg, Von Hofsten, et al. Acta Pediatrica, 2011).

Methods:  At 2 and 4 months corrected age, eye and head movements were measured when the infant tracked a moving object. The eye movements were analysed in terms of smooth pursuit and saccades (Vision Res, 37, 1997, 1799; Exp Brain Res, 146, 2002, 257). Accuracy of gaze, proportion of smooth pursuit, head movements and saccades were calculated.

Results:  Between 2 and 4 months of age, all infants improved their ability to smoothly pursue a moving object. However, at both occasions, the preterm infants had less proportion smooth pursuit than the full‐term infants. The groups did not differ with respect to gaze and head movements, but the saccade frequency was higher for the very preterms in some of the conditions.

Conclusion:  The development of smooth pursuit in the low‐risk preterm infant group was strongly delayed compared to typically developed infants. Thus, the 2 months or more extra visual experience did not have a distinguishable positive effect on visuo‐motor development as expressed in smooth pursuit.
Prevalence of congenital heart disease assessed by echocardiography in 2067 consecutive newborns
Authors: Ishikawa Takamichi , Iwashima Satoru , Ohishi Akira , Nakagawa Yuichi , Ohzeki Takehiko
Published: March 2011

Aim:  There are discrepancies in the reported prevalence of congenital heart disease (CHD). This study prospectively evaluated the prevalence of CHD in consecutive newborns using echocardiographic screening.

Methods:  A cohort screening study was conducted in an unselected series of all live‐birth newborns. Two‐dimensional and colour Doppler echocardiography was performed at 0–4 days of life in 2067 consecutive neonates who were born at the Hamamatsu University Hospital, Japan, between May 2005 and April 2010.

Results:  There were 104 cases of CHD in the 2067 live births. Ventricular septal defect and patent ductus arteriosus were the most frequent cardiac abnormalities. The prevalence of newborns with CHD who had signs or symptoms of CHD and/or required invasive intervention was 21.3 per 1000 live births. However, 60 patients (29.0 per 1000 live births) with CHD were asymptomatic and did not need invasive intervention. The overall prevalence of CHD in this series was 50.3 per 1000 live births.

Conclusion:  This prospective study using echocardiography for all newborns shows a higher prevalence of CHD than almost all of the previous studies.
Awake and asleep oxygen saturations in infants with chronic neonatal lung disease
Authors: Sykes Sarah , Kingshott Ruth , Primhak Robert
Published: March 2011

Aim:  There is uncertainty about the best method of withdrawing supplemental oxygen in babies with chronic neonatal lung disease (CNLD). Some authors advocate withdrawal of oxygen in the day, but continuing supplementation during sleep, based on early work suggesting that oxygen saturations are lower during sleep, which did not accord with our clinical impression. We re‐examined the hypothesis that babies have lower saturations while asleep.

Methods:  We studied infants with CNLD during the day, while awake and asleep. We recorded video with simultaneous real‐time capture of oxygen saturation (SpO2), heart rate and plethysmographic waveform from pulse oximetry. Behavioural state was scored using observation and video and classified as awake (feeding, active or quiet) or sleep.

Results:  Thirteen infants had analysable data, although one had strikingly lower SpO2 values while awake and was excluded from analysis. The infants had a median gestation of 26 weeks and were studied at a median (range) postmenstrual age of 66 (37–130) weeks, for 229 (89–330) min. Mean SpO2 was 97.6% during sleep and 97.0% awake (p = 0.011).

Conclusion:  Babies with CNLD have lower oxygen saturation while awake. There is no physiological justification for increasing oxygen during sleep, or withdrawing selectively during the daytime, although larger studies are needed to confirm this finding.
George Meredith’s Poetry and the Critical Imagination
Authors: Mitchell Rebecca N.
Published: March 2011

This article offers an overview of criticism of George Meredith’s poetry in the last century and a half and situates Meredith’s work within current and emergent trends in Victorian studies. The first section addresses the original critical response to Meredith’s verse and the early, influential studies that serve as the basis for later scholarship, noting the emphasis on ‘Modern Love’ to the near exclusion of Meredith’s corpus beyond that poem. It then traces the reasons for these limitations, including the access problems created by the lack of current print editions of Meredith’s poetry. Next, it surveys recent additions to Meredith criticism. The article concludes by suggesting scholarly and pedagogical directions for working with Meredith’s poetry, arguing that it is particularly well suited to the interdisciplinary, neoformalist, and narratological approaches now defining Victorian poetry scholarship.
Regulatory roles of hyaluronan in health and disease
Authors: Hascall Vincent , Karamanos Nikos
Published: March 2011

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Hyaluronan matrices in pathobiological processes
Authors: Wang Aimin , de la Motte Carol , Lauer Mark , Hascall Vincent
Published: March 2011

Hyaluronan matrices are ubiquitous in normal and pathological biological processes. This remarkable diversity is related to their unique mechanism of synthesis by hyaluronan synthases. These enzymes are normally activated in the plasma membrane and utilize cytosolic substrates directly to form these large polyanionic glycosaminoglycans, which are extruded directly into the extracellular space. The extracellular matrices that are formed interact with cell surface receptors, notably CD44, that often dictate the biological processes, as described in the accompanying minireviews of this series. This article focuses on the discovery in recent studies that many cell stress responses initiate the synthesis of a monocyte‐adhesive hyaluronan extracellular matrix, which forms a central focus for subsequent inflammatory processes that are modulated by the dialogue between the matrix and the inflammatory cells. The mechanisms involve active hyaluronan synthases at the cell membrane when cell stresses occur at physiological levels of glucose. However, dividing cells at hyperglycemic levels of glucose initiate the synthesis of hyaluronan in intracellular compartments, which induces endoplasmic reticulum stress and autophagy, processes that probably contribute greatly to diabetic pathologies.
Transcriptional and post‐translational regulation of hyaluronan synthesis
Authors: Tammi Raija H. , Passi Alberto G. , Rilla Kirsi , Karousou Evgenia , Vigetti Davide , Makkonen Katri , Tammi Markku I.
Published: March 2011

Hyaluronan, a ubiquitous high‐molecular‐mass glycinoglycan on cell surfaces and in extracellular matrices, has a number of specific signaling functions in cell–cell communication. Changes in its content, molecular mass and turnover rate are crucial for cell proliferation, migration and apoptosis, processes that control tissue remodeling during embryonic development, inflammation, injury and cancer. To maintain tissue homeostasis, the synthesis of hyaluronan must therefore be tightly controlled. In this review, we highlight some recent data on the transcriptional regulation of hyaluronan synthase (Has1–3) expression and on the post‐transcriptional control of hyaluronan synthase activity, which, in close association with the supply of the UDP‐sugar substrates of hyaluronan synthase, adjust the rate of hyaluronan synthesis.
Tec family kinases: Itk signaling and the development of NKT αβ and γδ T cells
Authors: Qi Qian , Kannan Arun Kumar , August Avery
Published: March 2011

The Tec family tyrosine kinase interleukin‐2 inducible T‐cell kinase (Itk) is predominantly expressed in T cells and has been shown to be critical for the development, function and differentiation of conventional αβ T cells. However, less is known about its role in nonconventional T cells such as NKT and γδ T cells. In this minireview, we discuss evidence for a role for Itk in the development of invariant NKT αβ cells, as well as a smaller population NKT‐like γδ T cells. We discuss how these cells take what could be the same signaling pathway regulated by Itk, and interpret it to give different outcomes with regards to development and function.
Lyman α emission from the first galaxies: signatures of accretion and infall in the presence of line trapping
Authors: Latif M. A. , Schleicher Dominik R. G. , Spaans M. , Zaroubi S.
Published: March 2011

The formation of the first galaxies is accompanied by large accretion flows and virialization shocks, during which the gas is shock heated to temperatures of ∼104 K, leading to potentially strong fluxes in the Lyman α line. Indeed, a number of Lyman α blobs have been detected at high redshift. In this Letter, we explore the origin of such Lyman α emission using cosmological hydrodynamical simulations that include a detailed model of atomic hydrogen as a multi-level atom and the effects of line trapping with the adaptive mesh refinement code flash. We see that baryons fall into the centre of a halo through cold streams of gas, giving rise to a Lyman α luminosity of at least 1044ergs−1 at z= 4.7, similar to the observed Lyman α blobs. We find that a Lyman α flux of 5.0 × 10−17ergcm-2s−1 emerges from the envelope of the halo rather than its centre, where the photons are efficiently trapped. Such emission can be probed in detail with the upcoming James Webb Space Telescope (JWST) and will constitute an important probe of gas infall and accretion.
Extrapolating the evolution of galaxy sizes to the epoch of reionization
Authors: Wyithe J. Stuart B. , Loeb Abraham
Published: March 2011

We use data on the high-redshift evolution of the size distribution and luminosity function of galaxies to constrain the relationship between their star formation efficiency and starburst lifetime. Based on the derived scaling relations, we predict the angular sizes and average surface brightnesses of faint galaxies that will be discovered withJWST. We find thatJWSTwill be able to resolve galaxies at the magnitude limit mAB < 31 out to a redshift of z∼ 14. The next generation of large ground-based telescopes will resolve all galaxies discovered withJWST, provided they are sufficiently clumpy to enable detection above the bright thermal sky. We combine our constraints with simple models for self-regulation of star formation, and show that feedback from supernovae at redshifts z≳ 3 is likely mediated through momentum transfer, with the starburst time-scale set by the lifetime of the massive stars rather than the dynamical time in the host galactic disc.
Determining a correction factor for aerial surveys of harbor seals in California
Authors: Harvey James T. , Goley Dawn
Published: March 2011

Abstract

Counts of pinnipeds provide a minimal estimate of population size because some unknown proportion of individuals is in the water during surveys. We determined a correction factor (CF) for Pacific harbor seals (Phoca vitulina richardii) by estimating the proportion ashore of 180 seals tagged with flipper‐mounted radio tags throughout California. The mean proportions of tagged individuals ashore during four complete surveys in 2004 were not different between central and northern California (F= 1.85, P= 0.18) or between sexes (F= 0.57, P= 0.45), but a lesser proportion of weaners was ashore than subadults or adults (F= 7.97, P= 0.001), especially in northern California. The CF calculated for the statewide census of harbor seals was 1.65, using transmitters operating during the survey (n= 114). Using a mark‐recapture estimator for tag survival (phi) and the four telemetry surveys the mean CF for central and northern California was 1.54 ± 0.38 (95% CI). A CF for southern California of 2.86 was based on a single survey. Using the mean CF of 1.54 and a statewide count in 2009 we estimated 30,196 (95% CI = 22,745–37,647) harbor seals in California.
Muslim Women’s Religious Education in Early and Classical Islam
Authors: Sayeed Asma
Published: March 2011

This article explores the main trajectories of contemporary scholarship on women and religious learning in early and classical Islam. It focuses on women’s transmission of (sayings attributed to the Prophet which are decisive in formulating Islamic laws, rituals, and creed). The article reviews the main points of legal discourse on the permissibility of educating women and surveys contributions in the arena of social history which have illuminated various aspects of women’s religious education in early and classical Islam. In the process, the author proposes questions for future studies in this area.
Modern Ayurveda in Transnational Context
Authors: Warrier Maya
Published: March 2011

Ayurveda, the ancient system of Indian medicine rooted in Hindu and Buddhist cosmologies, remained relatively under‐researched in the humanities and social sciences until the 1970s. It is only in the last four decades that it has received significant scholarly attention, from Indologists and Sanskritists, as well as historians, anthropologists and sociologists. In recent times, the volume of research on modern and transnational Ayurveda has grown, not least because of the growing popularity of this tradition in Western Europe and North America. This survey offers a brief overview of scholarship on the ‘classical’ or ‘traditional’ form of Ayurveda elaborated in ancient Sanskrit texts, before going on to review literature tracing the development of modern Ayurveda both in postcolonial South Asia, as well as in global and transnational settings.
Phonetic and Phonological Factors in the Second Language Production of Phonemes and Phonotactics
Authors: Davidson Lisa
Published: March 2011

The study of second language (L2) speech production has been informed by research in a number of areas, including phonological theory, acoustic phonetics, and articulatory phonetics. A synthesis of the research in these areas is presented in this paper. First, early theories about ‘foreign accents’ that have continued to influence current research are discussed, including the Contrastive Analysis Hypothesis and interlanguage. Next, we turn to the acquisition of consonants and vowels, which has been the subject of both experimental and theoretical investigations. The last section examines the acquisition of suprasegmental structure, such as syllables, phonotactics, and prosodic position. Several theories that elucidate the relative contributions of first language transfer and universal markedness are presented, such as the Markedness Differential Hypothesis and Optimality Theory. Both phonetic and phonological aspects of L2 production are considered in light of data from learners at all stages of language acquisition, from cross‐language speech production studies which may reflect the initial state of language learning to proficient L2 speakers.
Nested polymerase chain reaction–based detection of Dothistroma septosporum, red band needle blight of pine, a tool in support of phytosanitary regimes
Authors: LANGRELL STEPHEN R. H.
Published: March 2011

Red band needle blight is one of the most important foliar diseases of Pinus species and is of increasing international forest health and biosecurity concern. To provide a rapid identification technique for this pathogen in support of official control measures, a nested polymerase chain reaction–based diagnostic assay that employs species‐specific primer sets has been developed. The assay is able to detect the presence of the pathogen direct from pine needles, irrespective of host species, to within 10 fg of target DNA, the equivalent of approximately 2–3 ascospores or hyphael cells.
DNA barcoding of the ichthyofauna of Taal Lake, Philippines
Authors: AQUILINO SEAN V. L. , TANGO JAZZLYN M. , FONTANILLA IAN K. C. , PAGULAYAN ROBERTO C. , BASIAO ZUBAIDA U. , ONG PERRY S. , QUILANG JONAS P.
Published: March 2011

This study represents the first molecular survey of the ichthyofauna of Taal Lake and the first DNA barcoding attempt in Philippine fishes. Taal Lake, the third largest lake in the Philippines, is considered a very important fisheries resource and is home to the world’s only freshwater sardine, Sardinella tawilis. However, overexploitation and introduction of exotic fishes have caused a massive decline in the diversity of native species as well as in overall productivity of the lake. In this study, 118 individuals of 23 native, endemic and introduced fishes of Taal Lake were barcoded using the partial DNA sequence of the mitochondrial cytochrome c oxidase subunit I (COI) gene. These species belong to 21 genera, 17 families and 9 orders. Divergence of sequences within and between species was determined using Kimura 2‐parameter (K2P) distance model, and a neighbour‐joining tree was generated with 1000 bootstrap replications using the K2P model. All COI sequences for each of the 23 species were clearly discriminated among genera. The average within species, within genus, within family and within order percent genetic divergence was 0.60%, 11.07%, 17.67% and 24.08%, respectively. Our results provide evidence that COI DNA barcodes are effective for the rapid and accurate identification of fishes and for identifying certain species that need further taxonomic investigation.
DNA barcoding in closely related species: A case study of Primula L. sect. Proliferae Pax (Primulaceae) in China
Authors: YAN Hai‐Fei , HAO Gang , HU Chi‐Ming , GE Xue‐Jun
Published: March 2011

Abstract  DNA barcoding is a method of identifying species by analyzing one or a few short standardized DNA sequences. There are particular challenges in barcoding plants, especially for distinguishing closely related species. Hence, there is an urgent need to evaluate the performance of candidate loci for distinguishing between species, especially closely related species, to complement the rbcL + matK combination suggested as the core barcode for land plants. We sampled 48 individuals representing 12 species in Primula sect. Proliferae Pax in China to evaluate the performance of eight leading candidate barcode loci (matK, rbcL, rpoB, rpoC1, trnH‐psbA, psbK‐psbI, atpF‐atpH, and internal transcribed spacer (ITS)). The core combination rbcL+matK gave only 50% species resolution in sect. Proliferae. In terms of intraspecies and interspecies divergence, degree of monophyly, and sequence similarity, ITS, trnH‐psbA, and psbK‐psbI showed good performance as single‐locus barcodes. Internal transcribed spacer displayed the highest genetic divergence and best discriminatory power, both alone and in combination with rbcL+matK (83.3% species resolution). We recommend evaluating the use of ITS for barcoding in other species. Low or single copy nuclear regions would provide more sophisticated barcoding tools in the long term, even though further research is required to find suitable loci.
Chloroplast DNA variation and phylogeography of Ligularia tongolensis (Asteraceae), a species endemic to the Hengduan Mountains region of China
Authors: WANG Jin‐Feng , PAN Yue‐Zhi , GONG Xun , CHIANG Yu‐Chung , KURODA Chiaki
Published: March 2011

Abstract  In this research, we aimed to study the genetic variation and phylogeographic pattern of Ligularia tongolensis, a perennial herb endemic to the Hengduan Mountains region of China. We sequenced two chloroplast DNA (cpDNA) intergenic spacers (trnQ‐5′rps16, trnL‐rpl32) in 140 individuals from 14 populations of three groups (Jinshajiang vs. Yalongjiang vs. Wumeng) within this species range. High levels of haplotype diversity (Hd = 0.814) and total genetic diversity (Ht = 0.862) were detected at the species level, based on a total of 12 haplotypes identified. Low levels of intrapopulation diversity (Hs = 0.349), high levels of genetic divergence (Gst = 0.595, Nst = 0.614, Fst = 0.597), and the absence of isolation by distance tests were also found in L. tongolensis. Furthermore, H2 and H5, the dominant haplotypes that located at internal nodes and deviated from extinct ancestral haplotype in the network, were found to be shared between Jinshajiang and Yalongjiang groups. These results indicate that past fragmentation may be the important factor responsible for the present phylogeographical pattern of L. tongolensis. Meanwhile, the locations occupied by each group might have served as independent refugia for L. tongolensis during the Quaternary glaciation. Unimodal mismatch distribution and star‐like genealogies indicated this species underwent past demographic expansion events, with expansion ages of 274 ka BP.
Photometric observations of Earth‐impacting asteroid 2008 TC3
Authors: KOZUBAL Marek J. , GASDIA Forrest W. , DANTOWITZ Ronald F. , SCHEIRICH Peter , HARRIS Alan W.
Published: March 2011

Abstract– A calibrated lightcurve is presented of the near‐Earth asteroid 2008 TC3, obtained before it impacted Earth on October 7, 2008. The asteroid was observed in unfiltered images from the end of astronomical twilight until the object entered Earth’s shadow about 2 h later. The observations covered a wide range of phase angles from 14.79° to 2.93°, during which the asteroid ranged from 82,000 km to 29,000 km distance from the observer. A method is presented for obtaining photometrically filtered brightness values for the asteroid using unfiltered imaging techniques. Over 1,700 images of the asteroid produce a lightcurve with a peak‐to‐peak variation in V of 0.76 magnitude. Analysis of the lightcurve yields values for H = 30.86 ± 0.01 and G = 0.33 ± 0.03. Combined with other constraints on the kinetic energy and diameter of the asteroid, which suggest a low 1.8 g cm−3 density and albedo 0.05 ± 0.01, the value of H implies an asteroid of about 4.1 m in diameter, 28 m3 in volume, and 51,000 kg in mass. The determined value of G is out of range for normal, larger asteroids of albedo 0.05–0.15.
Does hydrophobicity always enhance antioxidant drugs? A cut-off effect of the chain length of functionalized chlorogenate esters on ROS-overexpressing fibroblasts
Authors: Laguerre Mickaël , Wrutniak-Cabello Chantal , Chabi Béatrice , López Giraldo Luis J , Lecomte Jérôme , Villeneuve Pierre , Cabello Gérard
Published: March 2011

Objectives

Phenolic antioxidants are currently attracting a growing interest as potential therapeutic agents to counteract diseases associated with oxidative stress. However, their high hydrophilicity results in a poor bioavailability hindering the development of efficient antioxidant strategies. A promising way to overcome this is to increase their hydrophobicity by lipophilic moiety grafting to form the newly coined ‘phenolipids’. Although hydrophobicity is generally considered as advantageous regarding antioxidant properties, it is nevertheless worth investigating whether increasing hydrophobicity necessarily leads to a more efficient antioxidant drug.

Methods

To answer this question, the antioxidant capacity of a homologous series of phenolics (chlorogenic acid and its methyl, butyl, octyl, dodecyl and hexadecyl esters) toward mitochondrial reactive oxygen species (ROS) generated in a ROS-overexpressing fibroblast cell line was investigated using 2′,7′-dichlorodihydrofluorescein.

Key findings

Overall, the long chain esters (dodecyl and hexadecyl esters) were more active than the short ones (methyl, butyl, and octyl esters), with an optimal activity for dodecyl chlorogenate. Moreover, dodecyl chlorogenate exerted a strong antioxidant capacity, for concentration and incubation time below the cytotoxicity threshold, making it a promising candidate for further in-vivo studies. More importantly, we found that the elongation of the chain length from 12 to 16 carbons led unexpectedly to a 45% decrease of antioxidant capacity.

Conclusion

The understanding of this sudden collapse of the antioxidant capacity through the cut-off theory will be discussed in this article, and may contribute towards development of a rational approach to design novel amphiphilic antioxidant drugs, especially phenolipids with medium fatty chain.
Dual inhibition: a novel promising pharmacological approach for different disease conditions
Authors: Patyar Sazal , Prakash Ajay , Medhi Bikash
Published: March 2011

To overcome the problems associated with polypharmacy, which include medication non compliance, adverse drug reactions, drug–drug interactions and increased pill-burden, various strategies, such as sustained-release drugs and fixed-dose combination regimens (polypills), have been developed. Out of these, a novel and very much promising approach is the use of dual-action drugs. Amongst the dual-action drugs, there is a class of compounds known as dual inhibitors, which possess the dual inhibitory activity. The most common examples of dual inhibitors are rivastigmine, ladostigil, asenapine, phenserine, amitriptyline, clomipramine, doxepin and desipramine. This review article focuses on the conventional drugs used in different diseases which possess dual inhibition activity as well as those which are still in the preclinical/clinical phase.
Montelukast, a cysteinyl leukotriene receptor-1 antagonist, attenuates chronic brain injury after focal cerebral ischaemia in mice and rats
Authors: Zhao Rui , Shi Wen-Zhen , Zhang Yong-Mei , Fang San-Hua , Wei Er-Qing
Published: March 2011

Objectives

Previously we demonstrated the neuroprotective effect of montelukast, a cysteinyl leukotriene receptor-1 (CysLT1) antagonist, on acute brain injury after focal cerebral ischaemia in mice. In this study, we have determined its effect on chronic brain injury after focal cerebral ischaemia in mice and rats.

Methods

After transient focal cerebral ischaemia was induced by middle cerebral artery occlusion, montelukast was intraperitoneally injected in mice or orally administered to rats for five days. Behavioural dysfunction, brain infarct volume, brain atrophy and neuron loss were determined to evaluate brain lesions.

Key findings

Montelukast (0.1 mg/kg) attenuated behavioural dysfunction, brain infarct volume, brain atrophy and neuron loss in mice, which was similar to pranlukast, another CysLT1 receptor antagonist. Oral montelukast (0.5 mg/kg) was effective in rats and was more effective than edaravone, a free radical scavenger.

Conclusion

Montelukast protected mice and rats against chronic brain injury after focal cerebral ischaemia, supporting the therapeutic potential of CysLT1 receptor antagonists.
Betulinic acid prevention of d-galactosamine/lipopolysaccharide liver toxicity is triggered by activation of Bcl-2 and antioxidant mechanisms
Authors: Zheng Zhan-Wei , Song Shun-Zong , Wu Yan-Ling , Lian Li-Hua , Wan Ying , Nan Ji-Xing
Published: March 2011

Objectives

The hepatoprotective activity and molecular mechanism of betulinic acid (BA) was investigated on acute liver failure induced by d-galactosamine (D-GalN)/lipopolysaccharide (LPS) in vivo.

Methods

Mice were administered with different doses of BA (20 mg/kg or 50 mg/kg, i.p.) 1 h before injection of D-GalN (700 mg/kg)/LPS (10 µg/kg) and sacrificed 6 h after treatment with D-GalN/LPS.

Key findings

Pretreatment with BA significantly prevented the increases of serum aspartate aminotransferase and alanine aminotransferase, while it increased the content of glutathione and catalase, and reduced malondialdehyde. BA showed obvious anti-oxidant effects and prevented D-GalN/LPS-induced apoptosis, as indicated by DNA ladder. BA treatment resulted in regulation of the mitogen-activated protein kinase. We found that BA mediated production of c-jun NH2-terminal protein kinase and extracellular signal-regulated kinase induced by D-GalN/LPS, promoted the expression of B-cell CLL/lymphoma 2 (Bcl-2) and restored mitochondrial outer membrane permeabilization.

Conclusions

The results suggested that BA prevented D-GalN/LPS-induced acute liver failure by upregulation of Bcl-2 and antioxidation and mediation of cytokines causing apoptotic cell death and lessened liver damage.
Differential disposition of intra-renal generated and preformed glucuronides: studies with 4-methylumbelliferone and 4-methylumbelliferyl glucuronide in the filtering and nonfiltering isolated perfused rat kidney
Authors: Wang Jiping , Evans Allan M , Knights Kathleen M , Miners John O
Published: March 2011

Objectives

This study was designed to investigate the renal disposition of 4-methylumbelliferone (4MU) and 4-methylumbelliferyl glucuronide (4MUG) to characterise the contribution of excretion and metabolic clearance to total clearance in the kidney.

Methods

The isolated perfused kidney (IPK) from the male Sprague–Dawley rat was used in filtering and non-filtering mode to study the renal disposition of 4MU, renally generated 4MUG and preformed 4MUG. Perfusate and urine (filtering IPK only) was collected for up to 120 min and 4MU and 4MUG in perfusate and urine were determined by HPLC. Analytes were also measured in kidney tissue collected at 120 min. Non-compartmental analysis was used to derive pharmacokinetic parameters.

Key findings

The concentration of 4MU in perfusate declined with a terminal half-life of approximately 120 min following administration to the filtering IPK and nonfiltering IPK. There was a corresponding increase in the concentration of 4MUG. Metabolic clearance of 4MU accounted for 92% of total renal clearance. After bolus dosing of preformed 4MUG in the perfusion reservoir of the filtering IPK, the perfusate concentration declined with the terminal half-life of approximately 260 min. The renal excretory clearance of preformed 4MUG accounted for 96% of total renal clearance. 4MU was extensively metabolized by glucuronidation in the filtering and nonfiltering IPK, and the total renal clearance of 4MU was far greater than its renal excretory clearance. This indicated that glucuronidation was the major elimination pathway for 4MU in the kidney.

Conclusions

The data confirmed an important role for the kidney in the metabolic clearance of xenobiotics via glucuronidation and signalled the lack of impact of impaired glomerular filtration on renal drug metabolism.
Resources and time pressure as day‐level antecedents of work engagement
Authors: Kühnel Jana , Sonnentag Sabine , Bledow Ronald
Published: March 2011

This diary study adds to research on the Job Demands‐Resources model. We test main propositions of this model on the level of daily processes, namely, additive and interaction effects of day‐specific job demands and day‐specific job and personal resources on day‐specific work engagement. One hundred and fourteen employees completed electronic questionnaires three times a day over the course of one working week. Hierarchical linear models indicated that day‐specific resources (psychological climate, job control, and being recovered in the morning) promoted work engagement. As predicted, day‐specific job control qualified the relationship between day‐specific time pressure and work engagement: on days with higher job control, time pressure was beneficial for work engagement. On days with lower job control, time pressure was detrimental for work engagement. We discuss our findings and contextualize them in the current literature on dynamic and emergent job characteristics.
Influence of Flow Structure on Compound Angled Film Cooling Effectiveness and Heat Transfer
Authors: Aga Vipluv , Abhari Reza S.
Published: March 2011

Film cooling in turbine blades involves injecting cold air through small holes over the surface of the blade to thermally protect it against the incoming hot freestream. Compound angled film cooling, in which the injected jet is angled laterally with respect to the streamwise flow direction, is used in industrial designs owing to their lower cost of manufacture compared with shaped geometries but a high coolant spread. The current study incorporates flow structure measurements of film cooling injection flows inclined at 30 deg to a flat surface with lateral angles of 15 deg, 60 deg, and 90 deg to the freestream. Blowing ratios of 1–2 and density ratios of 1–1.5 are studied. Three dimensional velocity measurements are carried out through high resolution stereoscopic particle image velocimetry. It is observed that the typical counter-rotating vortex pair structure associated with streamwise coolant injection is replaced with a single large vortex, which causes a more lateral spread of the coolant. Infrared thermography measurements are made for the same operating points using the super position principle, which allows calculation of adiabatic effectiveness and heat transfer coefficient. The adiabatic effectiveness is high at low blowing ratios for compound angled injection due to greater proximity of the coolant jet to the wall. At higher blowing ratios, the detrimental effects on effectiveness due to jet lift-off are counteracted by the greater coolant spread due to asymmetric primary vorticity. The heat transfer coefficient is also enhanced especially in the downstream region for high compound angles. The average heat transfer coefficient due to very large compound angles is not very sensitive to changing momentum flux ratios.