bluuebunny/crossref_metadata_2025 huggingface dataset:
P/Q‐type calcium channel modulators
Authors: Nimmrich V , Gross G
Published: June 2012

P/Q‐type calcium channels are high‐voltage‐gated calcium channels contributing to vesicle release at synaptic terminals. A number of neurological diseases have been attributed to malfunctioning of P/Q channels, including ataxia, migraine and Alzheimer's disease. To date, only two specific P/Q‐type blockers are known: both are peptides deriving from the spider venom of Agelenopsis aperta, ω‐agatoxins. Other peptidic calcium channel blockers with activity at P/Q channels are available, albeit with less selectivity. A number of low molecular weight compounds modulate P/Q‐type currents with different characteristics, and some exhibit a peculiar bidirectional pattern of modulation. Interestingly, there are a number of therapeutics in clinical use, which also show P/Q channel activity. Because selectivity as well as the exact mode of action is different between all P/Q‐type channel modulators, the interpretation of clinical and experimental data is complicated and needs a comprehensive understanding of their target profile. The situation is further complicated by the fact that information on potency varies vastly in the literature, which may be the result of different experimental systems, conditions or the splice variants of the P/Q channel. This review attempts to provide a comprehensive overview of the compounds available that affect the P/Q‐type channel and should help with the interpretation of results of in vitro experiments and animal models. It also aims to explain some clinical observations by implementing current knowledge about P/Q channel modulation of therapeutically used non‐selective drugs. Chances and challenges of the development of P/Q channel‐selective molecules are discussed.
Spectrum of toxic hepatitis following intentional paraquat ingestion: analysis of 187 cases
Authors: Yang Chin‐Jung , Lin Ja‐Liang , Lin‐Tan Dan‐Tzu , Weng Cheng‐Hao , Hsu Ching‐Wei , Lee Shen‐Yang , Lee Shwu‐Hua , Chang Chia‐Ming , Lin Wey‐Ran , Yen Tzung‐Hai
Published: June 2012

Introduction

This retrospective observational study examined the clinical features, the degrees of toxic hepatitis, physiological markers and clinical outcomes after intentional paraquat poisoning and sought to determine what association, if any, might exist between these findings.

Methods

A total of 187 patients were referred for management of intentional paraquat ingestion between 2000 and 2010. Patients were categorized into two groups according to their hepatic complication, i.e. with (N = 87) or without (N = 100) toxic hepatitis. Demographic, clinical and laboratory data were obtained for analysis. Mortality rates were also analysed.

Results

It was found that patients with toxic hepatitis were younger (39.7 ± 13.7 vs 44.2 ± 16.6 year old, P = 0.046), and suffered from greater incidences of acute respiratory failure (63.2 vs 48.0%, P = 0.037) and acute renal failure (75.9 vs 56.0%, P = 0.004) than patients without hepatitis. The hospitalization period was longer in patients with hepatitis than without hepatitis (16.2 ± 14.6 vs 11.2 ± 12.1 days, P = 0.012), even though there was no difference in mortality rate between both groups (56.3 vs 53.0%, P = 0.649). Notably, the symptoms of toxic hepatitis developed within 6.7 ± 6.3 days of exposure to paraquat with aspartate aminotransferase (AST) 138 ± 156 U/L, alanine aminotransferase (ALT) 127 ± 114 U/L and total bilirubin 2.7 ± 2.6 mg/dL. The hepatitis peaked at 9.5 ± 8.8 days with AST 125 ± 139 U/L, ALT 183 ± 181 U/L and total bilirubin 3.2 ± 3.6 mg/dL. Nevertheless, the symptoms resolved within 17.3 ± 9.8 days of paraquat exposure, and none of the patients died of hepatic complication.

Conclusions

A substantial proportion of paraquat patients suffered from hepatic complication (46.52%), but the spectrum of hepatitis in these patients seemed mild and transient.
Your Eyes Say “No,” But Your Heart Says “Yes”: Behavioral and Psychophysiological Indices in Infant Quantitative Processing
Authors: Brez Caitlin C. , Colombo John
Published: June 2012

Behavioral indices (e.g., infant looking) are predominantly used in studies of infant cognition, but psychophysiological measures have been increasingly integrated into common infant paradigms. The current study reports a result in which behavioral measures and physiological measures were both incorporated in a task designed to study infant number discrimination. Seven‐month‐old infants were habituated to several sets of stimuli varying in object type, but of a constant numerical value (either two or three items). Although looking time to each of the test trials revealed no differences, differences in heart rate defined measures of attention revealed infants’ ability to discriminate number. These findings imply that the inclusion of indices other than behavioral measures should become commonplace in studies of infant cognition.
An Investigation of Motivation to Transfer Second Language Learning
Authors: JAMES MARK ANDREW
Published: June 2012

Research on motivation in second language (L2) education has tended to focus on learning; this study took an alternative perspective, examining students’ motivation to transfer L2 learning. Data were gathered through semi‐structured interviews with 40 students who were enrolled in several sections of a university English‐for‐academic‐purposes (EAP) writing course and who were concurrently taking other academic courses in various disciplines. The interviews focused on whether students were motivated to transfer learning from the EAP course to their other courses and what factors influenced this motivation. Analysis of the interview data indicated that true motivation to transfer (i.e., a combination of desire, favorable attitudes, and effort) was rare. The factors that influenced these students’ motivation to transfer learning from the EAP course to their other courses fell into eight categories (e.g., perceptions of opportunity for transfer; personal beliefs about transfer). Implications of these findings for theory, practice, and future research related to L2 transfer motivation are discussed.
Business Takeover or New Venture? Individual and Environmental Determinants from a Cross–Country Study
Authors: Block Joern , Thurik Roy , van der Zwan Peter , Walter Sascha
Published: June 2012

Whereas the determinants of entrepreneurial choice have been thoroughly analyzed in the literature, little is known about the preferred mode of entry into entrepreneurship, such as taking over an existing business or starting a new venture. Using a large international data set, this study reports considerable differences in takeover preferences across 33 countries. Hierarchical (multilevel) regressions are performed to explore individual–level and country–level determinants of the preferred mode of entry. At the individual level, a person's human capital, risk attitude, and inventiveness influence the preference for starting a new venture versus taking over an existing business. At the country level, the culture–inherent level of risk tolerance, the country's level of innovation output, and the administrative difficulty of starting a new business are found to explain the between–country variation in the preferred mode of entry. Implications of our findings for research and practice are also discussed.
Early Challenges of Nascent Social Entrepreneurs
Authors: Renko Maija
Published: June 2012

Social entrepreneurs are celebrated as transformational leaders whose accomplishments create opportunities for those less fortunate. However, little is known about the early stages of social enterprise development. This study focuses on how a nascent entrepreneur's prosocial motivation affects the progress in building a new venture. Results show that prosocial motivation decreases the likelihood of firm emergence within a 4–year follow–up period, and even more so when the product offering of the emerging venture is new to the markets. These findings are discussed in the light of previous research on prosocial motivation, social entrepreneurship, market novelty, and nascent entrepreneurship.
The Biophysics and Biomechanics of Cryoballoon Ablation
Authors: ANDRADE JASON G. , DUBUC MARC , GUERRA PETER G. , MACLE LAURENT , MONDÉSERT BLANDINE , RIVARD LÉNA , ROY DENIS , TALAJIC MARIO , THIBAULT BERNARD , KHAIRY PAUL
Published: June 2012

Recent clinical and preclinical studies have demonstrated that cryothermal ablation using a balloon catheter (Artic Front®, Medtronic CryoCath LP, Pointe‐Claire, Canada) provides an effective means of achieving pulmonary vein isolation. This review explores the biophysics and biomechanics of cryoballoon ablation. Components of the cryoballoon catheter system are examined, mechanisms of cryothermal injury are summarized, and potential advantages of cryoballoon technology over standard radiofrequency ablation in isolating pulmonary veins are discussed. Practical aspects of biophysics and biomechanics relevant to the clinical electrophysiologist are emphasized, particularly with regards to the selection of the most appropriate cryoballoon catheter and minimizing peri‐procedural complications. (PACE 2012; 35:1162–1168)
Evolution of Variations in the Common Pattern of Stomatogenesis in Peritrich Ciliates: Evidence from a Comparative Study Including a New Description of Stomatogenesis in Pseudepistylis songi Peng et al.,
Authors: Wang Hongliang , Clamp John C. , Shi Xinlu , Utz Laura R. P. , Liu Guijie
Published: June 2012

The stomatogenesis of peritrich ciliates is an important developmental process but has been studied relatively little for such a large, diverse taxon. Complex oral structures and an inability of staining techniques to reveal them clearly have been the major factors hindering investigation of this process. In the present study, an improved method of staining with protargol was used to investigate the entire process of stomatogenesis in a large, colonial species of peritrich, Pseudepistylis songi, and to compare it to descriptions of stomatogenesis in several other species. We found that P. songi and other peritrichs have the same general type of ophryobuccokinetal stomatogenesis, with the parental oral complex being inherited by one daughter and the new oral complex by the other daughter; however, some differences between individual taxa appear to have arisen in the course of evolution. Reorganization of the entire germinal kinety (Gk) to form the germinal anlage may be plesiomorphic, with restriction of reorganization to its abstomal part being apomorphic. Development of the entire new haplokinety of one daughter cell (2Hk) from the germinal band or its homologue also appears to be plesiomorphic, with development of peristomial and infundibular parts of 2Hk from separate rudiments being apomorphic. Furthermore, development of the new Gk of the parental oral complex (1Gk) from the entire infundibular part of the parental haplokinety (1Hk) may be plesiomorphic, and development from just the abstomal part may be apomorphic. Finally, development of the Gk of the new oral complex (2Gk) from residual kinetosomes of the germinal band appears to be plesiomorphic.
Primary cutaneous anaplastic large cell lymphoma shows a distinct miRNA expression profile and reveals differences from tumor‐stage mycosis fungoides
Authors: Benner Marchina F. , Ballabio Erica , van Kester Marloes S. , Saunders Nigel J. , Vermeer Maarten H. , Willemze Rein , Lawrie Charles H. , Tensen Cornelis P.
Published: June 2012

The miRNA expression profiles of skin biopsies from 14 primary cutaneous anaplastic large cell lymphoma (C‐ALCL) patients were analysed with miRNA microarrays using the same control group of 12 benign inflammatory dermatoses (BID) as previously used to study the miRNA expression profile of tumor‐stage mycosis fungoides (MF). We identified 13 differentially expressed miRNAs between C‐ALCL and BID. The up‐regulation of miR‐155, miR‐27b, miR‐30c and miR‐29b in C‐ALCL was validated by miRNA‐Q‐PCR on independent study groups. Additionally, the miRNA expression profiles of C‐ALCL were compared with those of tumor‐stage MF. Although miRNA microarray analysis did not identify statistically significant differentially expressed miRNAs, miRNA‐Q‐PCR demonstrated statistically significantly differential expression of miR‐155, miR‐27b, miR‐93, miR‐29b and miR‐92a between tumor‐stage MF and C‐ALCL. This study, the first describing the miRNA expression profile of C‐ALCL, reveals differences with tumor‐stage MF, suggesting a different contribution to the pathogenesis of these lymphomas.
Salivary gland hypofunction induced by activation of innate immunity is dependent on type I interferon signaling
Authors: Nandula Seshagiri‐Rao , Dey Paromita , Corbin Kathryn L. , Nunemaker Craig S. , Bagavant Harini , Deshmukh Umesh S.
Published: June 2012

Background:  Activation of innate immunity through polyinosinic:polycytidylic acid [poly(I:C)] causes acute salivary gland hypofunction. As a major consequence of poly(I:C) treatment is type I interferon (IFN) production, this study was undertaken to investigate their role in salivary gland dysfunction.

Methods:  Different strains of mice deficient in either interferon alpha receptor (IFNAR1−/−) or IL‐6−/−, or IL‐10−/−, or EBI3−/− were treated with poly(I:C). Salivary gland function was determined by measuring pilocarpine‐induced saliva volume. Gene expression levels were measured by real‐time PCR. Ca2+ mobilization studies were performed using ex‐vivo acinar cells.

Results:  A single injection of poly(I:C) rapidly induced salivary gland hypofunction in wild‐type B6 mice (41% drop in saliva volumes compared to PBS‐treated mice). In contrast, the loss of function in poly(I:C)‐treated IFNAR−/− mice was only 9.6%. Gene expression analysis showed reduced levels of Il‐6, Il‐10, and Il‐27 in submandibular glands of poly(I:C)‐treated IFNAR−/− mice. While salivary gland dysfunction in poly(I:C)‐treated IL‐10−/− and EBI3−/− mice was comparable to wild‐type mice, the IL‐6−/− mice were more resistant, with only a 21% drop in function. Pilocarpine‐induced Ca2+ flux was significantly suppressed in acinar cells obtained from poly(I:C)‐treated wild‐type mice.

Conclusions:  Our data demonstrate that a combined action of type I IFNs and IL‐6 contributes toward salivary gland hypofunction. This happens through interference with Ca2+ mobilization within acinar cells. Thus, in acute viral infections and diseases like Sjögren’s syndrome, elevated levels of type I IFNs and IL‐6 can directly affect glandular function.
Employment of Young Adults With Disabilities in Dubai—A Case Study
Authors: Alborno Nadera , Gaad Eman
Published: June 2012

The authors investigated the implementation of the United Arab Emirates Federal Law regarding the employment of people with disabilities. They used a case study evaluation of an employment program initiated by a private national landscaping company in Dubai providing training and employment opportunities for young adults with varied physical and intellectual disabilities. The study examined the effects of the program since its inception in 2006, evaluating it with respect to employees' productivity and their psychological, behavioral, and professional development as well as the impact of the program on the work environment and the society in general. The methodology employed a qualitative social constructivist paradigm where the intent was to develop an in‐depth exploration of a central phenomenon. The findings showed that the program was successful in offering 36 adults with various physical and intellectual disabilities the opportunity of sustainable employment and provided each one of them with a source of livelihood, a chance for building social contacts, and more importantly self‐esteem—which is a main construct in empowering people with disabilities to integrate in their communities.
Health and Social Functioning of Adults With Intellectual Disability and Autism
Authors: Underwood Lisa , McCarthy Jane , Tsakanikos Elias , Howlin Patricia , Bouras Nick , Craig Tom K. J.
Published: June 2012

There is little information on the mental health needs of adults with intellectual disability (ID) and autism spectrum disorders (ASDs). Such evidence is much needed for the development of more effective mental health services for this group. The aim of this study is to compare adults with ID and ASD receiving specialist mental health services with participants without ASD. Data were collected from the anonymized case records of a clinic‐based population in South East London. Health and social functioning were measured using the Health of the Nation Outcome Scale for people with Learning Disability (HoNOS‐LD). A review of case records identified 371 service users in receipt of specialist mental health care who were eligible for the study. There were 117 people (32% of the sample) with a clinical diagnosis of ID and ASD. Participants with ASD were younger, more likely to be male, less likely to live independently and had more severe ID than those without ASD. Furthermore, those with ID and ASD were less likely to be diagnosed with a psychiatric disorder but had significantly higher scores on the HoNOS‐LD (indicating lower health and social functioning) than those without ASD. A significant proportion of adults with ID who are in receipt of specialist mental health services also have a clinical diagnosis of ASD. This group has different mental health needs compared with those without ASD. The authors note the need for a more personalized approach to service delivery with a focus on improving social functioning and behavioral impairments.
Unmet Healthcare and Social Services Needs of Older Canadian Adults With Developmental Disabilities
Authors: Shooshtari Shahin , Naghipur Saba , Zhang Jin
Published: June 2012

The authors sought to create a demographic, socioeconomic, and health‐related profile of older (40+) Canadian adults with developmental disabilities (DD) residing in their communities, and to enhance current knowledge of their unmet health and social support services needs. They provide a secondary analysis of cross‐sectional data from the 2001 and 2006 Participation and Activity Limitation Surveys (PALS). The study population comprised PALS respondents who: (a) were at least 40 years of age at the time of the survey and (b) were reported having a DD. Weighted data were used to describe and compare the profiles of the study population and the comparison group (PALS respondents age 40+ with other types of disability), and to estimate the prevalence of reported unmet healthcare and social support services needs. Logistic regression analyses determined the extent to which these needs affected the target population's overall health status. The data revealed that an estimated 136,570 Canadians age 15+ reported having a DD in 2006. Of these, 66,560 (48.7%) were at least 40 years of age. An estimated 47.7% of this population rated their overall health status as either fair or poor. The prevalence of reported unmet healthcare and social services needs decreased between 2001 and 2006 for both study groups, but it was still much higher for older individuals with DD than for the comparison group in 2001 and 2006. Controlling for the effects of all the other factors, the authors found that reported unmet needs did not significantly affect respondents' overall health status. The authors concluded that compared to Canadians with other types of disability, those with DD were more likely to report unmet healthcare and social support services needs. Further research is needed to explore policies and programs which support the healthy and active aging of this population.
Energy distribution patterns in Australia and its relationship to age, gender and body mass index among children and adults
Authors: FAYET Flavia , MORTENSEN Andrea , BAGHURST Katrine
Published: June 2012

Aim:  To assess daily energy distribution among Australians, provide evidence on the relative importance of eating occasions to energy intake and its relationship to age, gender and body mass index.

Methods:  Dietary data collected via 24‐hour recalls during the 1995 National Nutrition Survey (n = 10 851 adults) and the 2007 National Children's Nutrition and Physical Activity Survey (4837 = children) were analysed. Percentage of total energy intake was tabulated according to time, eating occasions, body mass index, age and gender.

Results:  The Australians consumed three main meals and two to three snacks, with the highest energy intake at ‘dinner’. Among children, ‘breakfast’ accounted for 15% of the energy, ‘lunch’ 19%, ‘dinner’ 30% and ‘snacks’ 35%. For adults, energy from ‘breakfast’ was 14%, ‘lunch’ 21%, ‘dinner’ 37% and ‘snacks’ 28%. Younger children and older adults consumed a lower per cent energy during the later part of the day. No difference in energy distribution was observed by gender. No difference in body mass index was observed for children and inconsistent differences were seen for adults.

Conclusion:  A high proportion of energy was consumed at ‘dinner’, but snacks were also an important source of energy intake. A variety of energy distribution patterns appear to be moderated by age. Older children consumed significantly less at breakfast and more snacks than younger children. In contrast, older adults consumed more energy at breakfast and less as snacks compared with younger adults. The findings indicate some key messages for informing primary prevention strategies among specific age groups including the need to attain a more even distribution of energy throughout the day.
Fast Determination of Royal Jelly Freshness by a Chromogenic Reaction
Authors: Zheng Huo‐Qing , Wei Wen‐Ting , Wu Li‐Ming , Hu Fu‐Liang , Dietemann Vincent
Published: June 2012

Abstract:  Royal jelly is one of the most important products of honeybees. Given its role in development of bee brood into fertile individuals of the royal caste it is also used in health products for human consumption. Royal jelly spoils and loses its health‐promoting properties depending on storage duration and conditions. To ensure product quality before selling, it is therefore necessary to assess royal jelly freshness. Many indexes of freshness have been suggested, but they all lack reliability or require complex and time‐consuming analyses. Here we describe a method to detect royal jelly freshness based on a chromogenic reaction between royal jelly and HCl. We demonstrate that analyses based on color parameters allow for the discrimination of royal jelly samples based on the duration of their storage. Color parameters of royal jelly stored at −18 and 4 °C for 28 d remained comparable to that of fresh samples, which supports the reliability of the method. The method of freshness determination described is practical, cheap, and fast and can thus be used in real‐time when trading royal jelly.

Practical Application:  The method developed can be used to assess royal jelly freshness. It is practical, cheap, and fast and can thus be used in real‐time when trading royal jelly.
Isolation and Identification of an Exopolysaccharide‐Producing Lactic Acid Bacterium Strain from Chinese Paocai and Biosorption of Pb(II) by Its Exopolysaccharide
Authors: Feng Meiqin , Chen Xiaohong , Li Chengcheng , Nurgul Rahman , Dong Mingsheng
Published: June 2012

Abstract:  Lactic acid bacteria isolated from various traditional Chinese fermented foods were screened for the production of exopolysaccharides (EPS). The strain 70810 from Chinese Paocai, which was identified as Lactobacillus plantarum (HQ259238) by morphological, physiological, biochemical, and 16S rDNA tests, was selected due to its highest EPS production capability (0.859 g/L) for further study. Biosorption of Pb(II) from aqueous solutions by 70810 EPS was studied with parameters of initial pH, contact time, initial Pb(II) concentration, adsorbent dosage, and temperature, respectively. Maximum adsorption of Pb(II) was observed at pH 5, 30 °C, and 6 h, respectively. The adsorption capacity was also found to be dependent upon initial Pb(II) concentration and adsorbent dosage. Surface adsorption of the metal at surface of 70810 EPS was confirmed through scanning electron microscopy. Fourier transform infrared spectroscopy spectra analysis indicated that some functional groups (for example, –OH, COO–, C=O, and –NH) of 70810 EPS were involved in Pb(II) biosorption process.

Practical Application:  Lactobacillus plantarum 70810 can be used as a starter culture for the production of some fermented foods (for example, yoghurt or fermented soybean milk) and the production of EPS that can meet consumer′s demand for products with low levels of additives. The EPS may be used as a potential biosorbent for the removal of heavy metal from environment and these fermented foods maybe have the potential effect to excrete lead from human body.
Isolation and Characterization of Cronobacter from Desiccated Foods in Korea
Authors: Chon Jung‐Whan , Song Kwang‐Young , Kim Sun‐Young , Hyeon Ji‐Yeon , Seo Kun‐Ho
Published: June 2012

Abstract:  A total of 115 desiccated food samples, including agricultural and marine products, were investigated for the presence of Cronobacter. Cronobacter species were characterized with biochemical tests. Antibiotic resistance was assessed with the disk diffusion method, and the molecular subtypes of Cronobacter isolates were identified using an automated repetitive sequence‐based PCR (rep‐PCR) system. A total of 18 (15.7%) Cronobacter strains were isolated from 115 desiccated food products. Fifteen Cronobacter isolates were C. sakazakii (13%), followed by 2 C. dublinensis (1.7%), and 1 C. universalis (0.9%). The most common antibiotic resistance of Cronobacter observed was against cephalothin (77.8%) followed by ampicillin (5.6%). With exception of 2 strains, all Cronobacter strains isolated from different sources were successfully differentiated by using the automated rep‐PCR system, indicating that it can be used for the purpose of contamination or outbreak source tracking of the bacteria.
HEGEL'S LEGACY
Authors: ZAMBRANA ROCÍO
Published: June 2012

abstract

Answering the challenge of G. W. F. Hegel's idealism and its perceived logocentrism has arguably been a defining feature of nineteenth‐ and twentieth‐century continental philosophy. Today, in the midst of a Hegel renaissance, Hegel's legacy within continental philosophy is far more ambivalent. In this essay, I cut across debates about the status of Hegel's idealism in order to offer a reflection on the legacy of Hegel by reconstructing a Hegelian notion of legacy. I develop this notion in response to Jacques Derrida's discussion of inheritance in Specters of Marx (1993). Both Hegel and Derrida articulate the structure of legacy, inheritance, and history on the basis of the strictures of gathering. For both, gathering is an act of memory that determines a legacy as a legacy, a history as a history. Gathering determines an event, norm, idea, or institution as something to be passed on for a future to come. While Derrida concludes that inheritance implies decision, Hegel's recollection provides the basis for what I will call a critical history, which contributes to any such decision in crucial ways.
Simulations of Multiphase Particle Deposition on Endwall Film-Cooling Holes in Transverse Trenches
Authors: Lawson Seth A. , Thole Karen A.
Published: June 2012

Integrated gasification combined cycle (IGCC) power plants allow for increased efficiency and reduced emissions as compared to pulverized coal plants. A concern with IGCCs is that impurities in the fuel from the gasification of coal can deposit on turbine components reducing the performance of sophisticated film-cooling geometries. Studies have shown that recessing a row of film-cooling holes in a transverse trench can improve cooling performance; however, the question remains as to whether or not these improvements exist in severe environments such as when particle deposition occurs. Dynamic simulations of deposition were completed using wax injection in a large-scale vane cascade with endwall film cooling. Endwall cooling effectiveness was quantified in two specific endwall locations using trenches with depths of 0.4D, 0.8D, and 1.2D, where D is the diameter of a film-cooling hole. The effects of trench depth, momentum flux ratio, and particle phase on adiabatic effectiveness were quantified using infrared thermography. Results showed that the 0.8D trench outperformed other geometries with and without deposition on the surface. Deposition of particles reduced the cooling effectiveness by as much as 15% at I = 0.23 with the trenched holes as compared to 30% for holes that were not placed in a transverse trench.
Influence of Coolant Flow Rate on Aero-Thermal Performance of a Rotor Blade Cascade With Endwall Film Cooling
Authors: Barigozzi G. , Fontaneto F. , Franchini G. , Perdichizzi A. , Maritano M. , Abram R.
Published: June 2012

This paper investigates the influence of coolant injection on the aerodynamic and thermal performance of a rotor blade cascade with endwall film cooling. A seven blade cascade of a high-pressure-rotor stage of a real gas turbine has been tested in a low speed wind tunnel for linear cascades. Coolant is injected through 10 cylindrical holes distributed along the blade pressure side. Tests have been preliminarily carried out at low Mach number (Ma2is = 0.3). Coolant-to-mainstream mass flow ratio has been varied in a range of values corresponding to inlet blowing ratios M1 = 0–4.0. Secondary flows have been surveyed by traversing a five-hole miniaturized aerodynamic probe in two downstream planes. Local and overall mixed-out secondary loss coefficient and vorticity distributions have been calculated from measured data. The thermal behavior has been also analyzed by using thermochromic liquid crystals technique to obtain film cooling effectiveness distributions. All this information, including overall loss production for variable injection conditions, allows us to draw a comprehensive picture of the aero-thermal flow field in the endwall region of a high pressure rotor blade cascade.
Experimental Investigation of Flow Boiling Instability in a Single Horizontal Microtube With and Without Inlet Restriction
Authors: Fan YanFeng , Hassan Ibrahim
Published: June 2012

An experimental study is conducted to investigate the effects of inlet restriction (orifice) on flow boiling instability in a single horizontal microtube. The test-section is composed of a stainless steel tube with an inner diameter of 889 μm, and a length of 150 mm. Experiments are performed for three different orifice configurations with 20%, 35%, and 50% area ratio. Mass flux is varied from 700 to 3000 kg/m2 · s, whereas the heat flux is varied from 6 to 27 W/cm2. The dielectric coolant FC-72 is selected as the working fluid. In the absence of an orifice at the inlet, four oscillation types are observed at the onset of flow instability; it is also noticed that the frequency of the oscillations increases with increasing heat flux, while the amplitude remains constant. The addition of an orifice at the inlet helps stabilizing the flow without generating significant pressure drop at the same operating condition as the microtube without orifice. The 20% area ratio orifice shows better performance at low mass fluxes (<1000 kg/m2 · s). Whereas, at high mass fluxes (>2000 kg/m2 · s), 50% and 35% area ratio orifices are efficient in stabilizing the flow or delaying the onset of flow instability. Therefore, selecting the area ratio of the orifice depends on the operating condition. A small area ratio orifice is preferably used at low mass fluxes, whereas a large area ratio orifice is more suitable for high mass fluxes.
Control-Oriented Modeling Requirements of a Direct-Drive Machine Tool Axis
Authors: Stephens Michael A. , Manzie Chris , Good Malcolm C.
Published: June 2012

The high performance demands on commercial computer numerical control (CNC) machine tools have led to the widespread adoption of direct-drive servo axes. In industrial machines, where the workpiece is manipulated by the axis, the plant dynamics seen by the control system may vary widely between different workpieces. These changing plant dynamics have been observed to lead to limit-cycle behavior for a given controller. In such a situation, conventional modeling approximations used by practitioners may fail to predict the onset of instability for these axes. This work demonstrates the failure of conventional modeling approximations to predict the observed instability in an industrial CNC servo axis and investigates the model fidelity required to replicate the observations. This represents an important consideration when designing model-based controllers for direct-drive axes in CNC machines.
Chemokine Gene Silencing in Decidual Stromal Cells Limits T Cell Access to the Maternal-Fetal Interface
Authors: Nancy Patrice , Tagliani Elisa , Tay Chin-Siean , Asp Patrik , Levy David E. , Erlebacher Adrian
Published: June 2012

Keeping Baby Safe

Because half the genes from a developing fetus are inherited from the father, from the mother's perspective, a fetus is “foreign.” How, then, does the maternal immune system tolerate the fetus?

Nancy
et al.

(p.
1317
) found that careful regulation of cellular recruitment signals allowed for fetal tolerance in mice. Although high numbers of T cells localized to the myometrium layer of the uterine wall in pregnant mice, very few T cells were found in the decidua, the uterine tissue that encapsulates the fetus and placenta. Thus, in pregnancy, regulation of immune cell localization may allow for organ-specific immune tolerance.
Interactions Between the Microbiota and the Immune System
Authors: Hooper Lora V. , Littman Dan R. , Macpherson Andrew J.
Published: June 2012

The large numbers of microorganisms that inhabit mammalian body surfaces have a highly coevolved relationship with the immune system. Although many of these microbes carry out functions that are critical for host physiology, they nevertheless pose the threat of breach with ensuing pathologies. The mammalian immune system plays an essential role in maintaining homeostasis with resident microbial communities, thus ensuring that the mutualistic nature of the host-microbial relationship is maintained. At the same time, resident bacteria profoundly shape mammalian immunity. Here, we review advances in our understanding of the interactions between resident microbes and the immune system and the implications of these findings for human health.
Coupled Activation and Degradation of eEF2K Regulates Protein Synthesis in Response to Genotoxic Stress
Authors: Kruiswijk Flore , Yuniati Laurensia , Magliozzi Roberto , Low Teck Yew , Lim Ratna , Bolder Renske , Mohammed Shabaz , Proud Christopher G. , Heck Albert J. R. , Pagano Michele , Guardavaccaro Daniele
Published: June 2012

DNA damage triggers the phosphorylation of factors involved in protein synthesis to regulate polypeptide elongation.
Development of Anti-Infectives Using Phage Display: Biological Agents against Bacteria, Viruses, and Parasites
Authors: Huang Johnny X. , Bishop-Hurley Sharon L. , Cooper Matthew A.
Published: June 2012

The vast majority of anti-infective therapeutics on the market or in development are small molecules; however, there is now a nascent pipeline of biological agents in development. Until recently, phage display technologies were used mainly to produce monoclonal antibodies (MAbs) targeted against cancer or inflammatory disease targets. Patent disputes impeded broad use of these methods and contributed to the dearth of candidates in the clinic during the 1990s. Today, however, phage display is recognized as a powerful tool for selecting novel peptides and antibodies that can bind to a wide range of antigens, ranging from whole cells to proteins and lipid targets. In this review, we highlight research that exploits phage display technology as a means of discovering novel therapeutics against infectious diseases, with a focus on antimicrobial peptides and antibodies in clinical or preclinical development. We discuss the different strategies and methods used to derive, select, and develop anti-infectives from phage display libraries and then highlight case studies of drug candidates in the process of development and commercialization. Advances in screening, manufacturing, and humanization technologies now mean that phage display can make a significant contribution in the fight against clinically important pathogens.
Panel of Prototypical Recombinant Infectious Molecular Clones Resistant to Nevirapine, Efavirenz, Etravirine, and Rilpivirine
Authors: Balamane Maya , Varghese Vici , Melikian George L. , Fessel W. Jeffrey , Katzenstein David A. , Shafer Robert W.
Published: June 2012

We created a panel of 10 representative multi-nonnucleoside reverse transcriptase inhibitor (NNRTI)-resistant recombinant infectious molecular HIV-1 clones to assist researchers studying NNRTI resistance or developing novel NNRTIs. The cloned viruses contain most of the major NNRTI resistance mutations and most of the significantly associated mutation pairs that we identified in two network analyses. Each virus in the panel has intermediate- or high-level resistance to all or three of the four most commonly used NNRTIs.
Small-Molecule Inhibitors of the LEDGF/p75 Binding Site of Integrase Block HIV Replication and Modulate Integrase Multimerization
Authors: Christ Frauke , Shaw Stephen , Demeulemeester Jonas , Desimmie Belete A. , Marchand Arnaud , Butler Scott , Smets Wim , Chaltin Patrick , Westby Mike , Debyser Zeger , Pickford Chris
Published: June 2012

Targeting the HIV integrase (HIV IN) is a clinically validated approach for designing novel anti-HIV therapies. We have previously described the discovery of a novel class of integration inhibitors, 2-(quinolin-3-yl)acetic acid derivatives, blocking HIV replication at a low micromolar concentration through binding in the LEDGF/p75 binding pocket of HIV integrase, hence referred to as LEDGINs. Here we report the detailed characterization of their mode of action. The design of novel and more potent analogues with nanomolar activity enabled full virological evaluation and a profound mechanistic study. As allosteric inhibitors, LEDGINs bind to the LEDGF/p75 binding pocket in integrase, thereby blocking the interaction with LEDGF/p75 and interfering indirectly with the catalytic activity of integrase. Detailed mechanism-of-action studies reveal that the allosteric mode of inhibition is likely caused by an effect on HIV-1 integrase oligomerization. The multimodal inhibition by LEDGINs results in a block in HIV integration and in a replication deficiency of progeny virus. The allosteric nature of LEDGINs leads to synergy in combination with the clinically approved active site HIV IN strand transfer inhibitor (INSTI) raltegravir, and cross-resistance profiling proves the distinct mode of action of LEDGINs and INSTIs. The allosteric nature of inhibition and compatibility with INSTIs underline an interest in further (clinical) development of LEDGINs.
Immune-Activating Properties of Panton-Valentine Leukocidin Improve the Outcome in a Model of Methicillin-Resistant Staphylococcus aureus Pneumonia
Authors: Yoong Pauline , Pier Gerald B.
Published: June 2012

The Panton-Valentine leukocidin (PVL) is a cytotoxin expressed by many methicillin-resistant
Staphylococcus aureus
(MRSA) strains that cause community-acquired infections (CA-MRSA). Its role in virulence however, is controversial, with clinical data suggesting that PVL-producing strains may cause less severe disease in humans. PVL is capable of lysing human white blood cells, but at sublytic amounts, PVL can activate protective host immunity in the absence of cell damage. The concentration-dependent reactions it elicits from host cells could be the reason for seemingly contradictory results about PVL's role in virulence. We hypothesized that a key to understanding PVL's action on host cells and, possibly, outcomes from infection is the amount of toxin present, a hypothesis previously supported in studies using a low-inoculum skin infection model, where low levels of PVL augmented innate immune resistance to infection. Here, we present additional data supporting this hypothesis using a mouse model of MRSA pneumonia, wherein we found increased virulence of isogenic Δ
pvl
strains and further confirmed PVL's capacity to activate proinflammatory responses from mouse and human neutrophils and pulmonary cells. Activation was measured as the production of phosphorylated p38 mitogen-activated protein kinase (MAPK) and proinflammatory cytokines interleukin-8 (IL-8) and KC (from human and mouse cells, respectively), as well as the release of antibacterial factors. Conversely, PVL lowered the levels of tumor necrosis factor alpha (TNF-α) produced in active pulmonary infection, while low doses induced apoptosis, suggesting that PVL also has the capacity to regulate inflammation. Our data indicate that, independent of its cytotoxic effects, PVL also plays an important and positive immunomodulatory role during MRSA infections.
Multilocus Sequence Analysis of Isolates of Achromobacter from Patients with Cystic Fibrosis Reveals Infecting Species Other than Achromobacter xylosoxidans
Authors: Ridderberg Winnie , Wang Mikala , Nørskov-Lauritsen Niels
Published: June 2012

A multilocus sequence analysis (MLSA) scheme was developed for characterization of strains and species from the genus
Achromobacter
, which are increasingly recovered from patients with cystic fibrosis (CF). Five conserved housekeeping genes were selected for the MLSA, which was applied to a diverse collection of 77 strains originating from Europe, Asia, and South America and including type strains of the seven recognized
Achromobacter
species, six environmental strains, eight non-CF clinical strains, and 56 CF clinical strains. The discriminatory power of MLSA, based on 2,098 nucleotides (nt), was much superior to a 16S rRNA gene comparison based on 1,309 nt. Congruence was observed between single-gene trees and a concatenated gene tree. MLSA differentiated all seven current
Achromobacter
species and also demonstrated the presence of at least four novel potential species within the genus. CF isolates were predominantly
Achromobacter xylosoxidans
(64%), an undescribed
Achromobacter
species (18%), and
Achromobacter ruhlandii
(7%). A clone of
Achromobacter
, which has spread among patients from Danish CF centers in Aarhus and Copenhagen, was identified as
Achromobacter ruhlandii
. MLSA facilitates the specific identification of isolates of
Achromobacter
necessary for describing their role in clinical infections.
Cold acclimation inhibits CO2-dependent stimulation of photosynthesis in spring wheat and spring rye
Authors: Dahal Keshav , Kane Khalil , Sarhan Fathey , Grodzinski Bernard , Hüner Norman P.A.
Published: June 2012

We assessed the effects of short-term elevated CO2 on the light-saturated rates of photosynthesis (Asat) of spring (‘SR4A’, ‘Katepwa’) and winter (‘Musketeer’, ‘Norstar’) wheat ( Triticum aestivum L.) and rye ( Secale cereale L.) cultivars grown at ambient CO2 (380 µmol C·mol–1) at either 20/16 °C (nonacclimated, NA) or 5/5 °C (cold acclimated, CA). In spring wheat–rye, cold acclimation decreased CO2-stimulation of Asat by 45%–60% relative to NA controls following a short-term (80 h) shift of plants from ambient to elevated CO2 (700 µmol C·mol–1). In contrast, in winter wheat–rye, cold acclimation enhanced CO2-stimulation of Asat by 15%–35% relative to NA controls upon a shift to elevated CO2. The stimulation observed for CA spring cultivars was about 60% less than that of CA winter cultivars. We conclude that a short-term exposure of spring cultivars to elevated CO2 cannot compensate for the cold acclimation-induced inhibition of Asat. Cold acclimation of spring cultivars appeared to exacerbate Rubisco CO2 substrate limitations present under ambient CO2. Furthermore, CA spring cultivars were unable to adjust their short-term temperature sensitivity of Asat under elevated CO2 compared with the winter cultivars.
Are the Great Plains wildrye (Elymus canadensis) and the Siberian wildrye (Elymus sibiricus) conspecific? A study based on the nuclear 5S rDNA sequences
Authors: Baum Bernard R. , Edwards Tara , Ponomareva Ekaterina , Johnson Douglas A.
Published: June 2012

Elymus canadensis L. and Elymus sibiricus L. are difficult to separate by morphology. The latter is found mainly in Asia and extends into northern North America; the former is confined to North America. We obtained the DNA sequences of 135 5S rDNA units collected from 19 localities throughout their respective ranges. The results of statistical parsimony, analysis of molecular variance, and sequence polymorphism analyses show that the two taxa are not conspecific.
Comparison of Puccinia acroptili from Eurasia and the USA
Authors: Bruckart W.L. , Eskandari F.M. , Berner D.K. , Aime M.C.
Published: June 2012

A rust disease caused by Puccinia acroptili P. Syd. & Syd. occurs throughout the range of Russian knapweed (Rhaponticum (syn. Acroptilon) repens), including North America. Differences in teliospore dimensions had been observed previously, but not quantified, between a specimen of P. acroptili from Turkey and one from the United States of America (USA). Similar differences were found during a recent evaluation of P. acroptili for biological control of R. repens in the USA; e.g., teliospores from eight USA isolates were 2.4 µm shorter (P = 0.05) than four isolates from Eurasia (two from Turkey, and one each from Russia and Kazakhstan). This inspired the generation of additional biological and DNA sequence data to clarify the significance of these differences between USA and Eurasian isolates. Although the USA isolates were found to have shorter teliospores, as noted in the description by Savile, teliospores of the USA isolates were also significantly wider in diameter than isolates from Eurasia; the latter in contrast to Savile’s observation. Biologically, the isolates were the same; all were equally aggressive in causing disease under common greenhouse test conditions, and fertile crosses occurred between isolates regardless of source. DNA sequence analyses of the nuclear rDNA large subunit and internal transcribed spacer regions supported the notion that P. acroptili is a single species, but it also revealed that small levels of variation may exist within the species. For these reasons, it has been concluded that USA and Eurasian accessions can be considered a single species, i.e., P. acroptili. Also, Savile’s observation about differences in spore dimensions is substantiated.
Reply to the discussion by J.W.F. Waldron and C.E. White on “Geochemical signature of Ordovician Mn-rich sedimentary rocks on the Avalonian shelf”1Appears in Canadian Journal of Earth Sciences, 2012, 49(6): 772–774 [doi: 10.1139/e2012-004].
Authors: Romer Rolf L. , Kroner Uwe
Published: June 2012

In their comment, Waldron and White state that manganese-rich sedimentary rocks of Nova Scotia and Wales are Cambrian and were deposited in a deep-water turbidite basin called “Megumia” rather than on the Avalonian shelf. Available geochronological data are not in conflict with an Early Ordovician deposition age for manganese-rich sedimentary rocks north of the Rheic suture, including those of Nova Scotia and northern Wales. “Megumia” is part of the Avalonian plate, and the manganese-rich sediments were deposited on its shelf.
BILINEAR FORM AND SOLITON SOLUTIONS FOR THE COUPLED NONLINEAR KLEIN–GORDON EQUATIONS
Authors: LI HE , MENG XIANG-HUA , TIAN BO
Published: June 2012

With the coupling of a scalar field, a generalization of the nonlinear Klein–Gordon equation which arises in the relativistic quantum mechanics and field theory, i.e., the coupled nonlinear Klein–Gordon equations, is investigated via the Hirota method. With the truncated Painlevé expansion at the constant level term with two singular manifolds, the coupled nonlinear Klein–Gordon equations are transformed to a bilinear form. Starting from the bilinear form, with symbolic computation, we obtain the N-soliton solutions for the coupled nonlinear Klein–Gordon equations.