bluuebunny/crossref_metadata_2025 huggingface dataset:
The symbolism of the Arab flag in modern Arab states: between commonality and uniqueness*
Authors: PODEH ELIE
Published: January 2011

ABSTRACT. The national flag, anthem and emblem are the three symbols through which an independent country proclaims its identity and sovereignty. Although each state has its distinctive flag, there are similarities in the flags of certain countries, such as in Scandinavia (the cross) and Africa (colours). These symbolise certain propinquity in terms of ideology, culture and history. Similarity is also to be found in the flags of the Arab countries: out of the twenty‐two current members of the Arab League, ten share the same colours on their flags (green, white, black and red), while a certain Islamic symbol (eagle, star) in some flags represents the uniqueness of that country. Of the other twelve countries, most rely on one colour of the four (usually red or green) while nine use Islamic symbols (stars, crescent and sword) on their flags. In spite of the importance of this national symbol, the study of the modern Arab flag is almost non‐existent. This article explores the modern evolution of the Arab flag and the reasons for the similarities in many Arab flags. In particular, it will deal with the pan‐Arab flags of the Hashemites Kingdom of the Hijaz (1916–26), Jordan, Iraq, Palestine, Syria and Egypt.
Time demands of caring for children with cerebral palsy: what are the implications for maternal mental health?
Authors: SAWYER MICHAEL G , BITTMAN MICHAEL , LA GRECA ANNETTE M , CRETTENDEN ANGELA D , BOROJEVIC NINA , RAGHAVENDRA PARIMALA , RUSSO RAY
Published: January 2011

Aim  To examine the relationship between maternal mental health problems and the time required by mothers to care for children with cerebral palsy (CP).

Method  Cross‐sectional study of 158 mothers of children with cerebral palsy (98 males, 60 females; mean age 11y 3mo, range 6–17y). Gross Motor Function Classification System levels of the children were 37% level I, 20% level II, 9% level III, 12% level IV, and 22% level V. Manual Ability Classification System levels were 19% level I, 27% level II, 22% level III, 13% level IV, and 19% level V. Maternal mental health problems were assessed using the General Health Questionnaire. Depressive symptoms were assessed using the Center for Epidemiological Studies Depression Scale. A time‐diary was used to measure caregiving time. Experience of time pressure was assessed using the Time Crunch Scale.

Results  On average, mothers spent 6.0 hours per 24 hours on weekdays and 8.3 hours per 24 hours on weekends caring for children with CP. There was a significant positive relationship between maternal psychological problems and both caregiving time required per 24 hours (p=0.03) and mothers’ experience of time pressure (p<0.001). There was also a significant positive association between maternal depressive symptoms and experience of time pressure (p=0.003).

Interpretation  It is important to support mothers to find ways of reducing the real and perceived impact of caregiving. This might include identifying sources of ‘respite’ support for caregivers, training in stress and time management, and appropriate treatment of mental health problems.
Decreased activity of the 20S proteasome in the brain white matter and gray matter of patients with multiple sclerosis
Authors: Zheng Jianzheng , Bizzozero Oscar A.
Published: January 2011

J. Neurochem. (2011) 117, 143–153.

Carbonylated (oxidized) proteins are known to accumulate in the cerebral white matter (WM) and gray matter (GM) of patients with multiple sclerosis (MS). Although oxidative stress is necessary for carbonyl generation, it is the failure of the degradation systems that ultimately leads to the build‐up of carbonylated proteins within tissues. In this study, we measured the activity of the 20S proteasome and other proteolytic systems in the cerebral WM and GM of 13 MS patients and 13 controls. We report that the activities of the three peptidases of the 20S proteasome (i.e. chymotrypsin‐like, caspase‐like and trypsin‐like) in both MS–WM and MS–GM are greatly reduced. Interestingly, neither the amount of proteasome nor the levels of the catalytic subunits (β1, β2, and β5) are diminished in this disease. Proteins containing Lys‐48 poly‐ubiquitin also accumulate in MS tissues, indicating failure of the 26S proteasome as well. Levels of the regulatory caps 11S α and 19S are also lower in MS than in controls, suggesting that the activity of the more complex proteasomes may be reduced further. Finally, the activities of other proteases that might also remove oxidized proteins (calpain, cathepsin B, mitochondrial LonP) are not lessened in MS. Together, these studies suggest that direct inactivation of proteolytic centers in the 20S particle and/or the presence of specific inhibitors is the underlying cause of proteasomal dysfunction in MS.
Modern carbonate microbialites from an asbestos open pit pond, Yukon, Canada
Authors: POWER I. M. , WILSON S. , DIPPLE G. M. , SOUTHAM G.
Published: January 2011

Microbialites were discovered in an open pit pond at an abandoned asbestos mine near Clinton Creek, Yukon, Canada. These microbialites are extremely young and presumably began forming soon after the mine closed in 1978. Detailed characterization of the periphyton and microbialites using light and scanning electron microscopy was coupled with mineralogical and isotopic analyses to investigate the mechanisms by which these microbialites formed. The microbialites are columnar in form (cm scale), have an internal spherulitic fabric (mm scale), and are mostly made of aragonite, which is supersaturated in the subsaline pond water. Initial precipitation is seen as acicular aragonite crystals nucleating onto microbial biomass and detrital particles. Continued precipitation entombs benthic diatoms (e.g. Brachysira vitrea), filamentous algae (e.g. Oedogonium sp.), dinoflagellates, and cyanobacteria. The presence of phototrophs at spherulite centers strongly suggests that these microbes play an important initial role in aragonite precipitation. Substantial growth of individual spherulites occurs abiotically through periodic precipitation of aragonite that forms concentric laminations around spherulite centers while pauses in spherulite growth allow for colonization by microbes. Aragonite associated with biomass (δ13C = −4.6‰ VPDB) showed a 13C‐enrichment of 0.8‰ relative to aragonite exhibiting no biomass (δ13C = −5.4‰ VPDB), which suggests a modest removal of isotopically light dissolved inorganic carbon by phototrophs. The combination of a low sedimentation rate, high calcification rate, and low microbial growth rate appears to result in the formation of these microbialites. The formation of microbialites at an historic mine site demonstrates that an anthropogenically constructed environment can foster microbial carbonate formation.
First selenosteid placoderms from the eastern Anti‐Atlas of Morocco; osteology, phylogeny and palaeogeographical implications
Authors: RÜCKLIN MARTIN
Published: January 2011

Abstract: A new placoderm assemblage is reported from the Kellwasser facies of the eastern Anti‐Atlas, Morocco. This is the first record of an abundant Frasnian placoderm assemblage from Africa. The following new selenosteid taxa are described:Draconichthys elegansgen. et sp. nov.,Enseosteus marocanensissp. nov. andWalterosteus lelievreisp. nov. In addition, material ofRhinosteuscf.parvulusis figured and described for the first time from Gondwana. The generaEnseosteus,RhinosteusandWalterosteusare reviewed. ‘Wildungenichthys’is regarded as a junior subjective synonym ofWalterosteus. The new material and a revision of the taxa from Bad Wildungen, Germany, are the basis for a new phylogenetic analysis of the selenosteid arthrodires. The monophyly of the selenosteids is confirmed. The North American selenosteids are a sister group of Moroccan and European selenosteids, excludingPachyosteus.The Moroccan vertebrate assemblage resembles that of Bad Wildungen. This supports the close palaeogeographical positions of Gondwana and Laurussia during the Late Devonian and indicates that biogeographical barriers for placoderms that could have separated the two assemblages were absent.
Do Control Effectiveness Disclosures Require SOX 404(b) Internal Control Audits? A Natural Experiment with Small U.S. Public Companies
Authors: KINNEY, JR. WILLIAM R. , SHEPARDSON MARCY L.
Published: January 2011

We use incremental and joint implementation of multiple SOX‐based control effectiveness disclosure and audit mandates to assess relative performance of alternatives for small U.S. public companies. Using data from several low‐ and high‐effort management disclosure and audit regimes implemented from 2003 to 2008, we find substantial and statistically significant increases in material weakness disclosure rates for small firms undergoing initial SOX 404(b) internal control audits, but find quantitatively and statistically similar increases for initial management reports of small firms exempt from such audits. As to audit cost, fees more than double for initial 404(b) audits in 2004 and remain high, while 404(b)‐exempt firms’ fees grow about 10% annually. Our results support the view that, for small firms, management internal control reports and traditional financial audits may be a cost effective disclosure alternative to full application of SOX 404(b). Also, our results suggest that, even without management reports on internal control, analysis of the cause of known accounting mistakes may yield substantial material weakness disclosures.
Endothelial dysfunction of rat coronary arteries after exposure to low concentrations of mercury is dependent on reactive oxygen species
Authors: Furieri Lorena B , Galán María , Avendaño María S , García‐Redondo Ana B , Aguado Andrea , Martínez Sonia , Cachofeiro Victoria , Bartolomé M Visitación , Alonso María J , Vassallo Dalton V , Salaices Mercedes
Published: January 2011

BACKGROUND AND PURPOSE Exposure to mercury is known to increase cardiovascular risk but the underlying mechanisms are not well explored. We analysed whether chronic exposure to low mercury doses affects endothelial modulation of the coronary circulation.

EXPERIMENTAL APPROACH Left coronary arteries and hearts from Wistar rats treated with either HgCl2 (first dose 4.6 µg·kg−1, subsequent doses 0.07 µg·kg−1 day−1, 30 days) or vehicle were used. Endothelial cells from pig coronary arteries incubated with HgCl2 were also used.

KEY RESULTS Mercury treatment increased 5‐HT‐induced vasoconstriction but reduced acetylcholine‐induced vasodilatation. It also reduced nitric oxide (NO) production and the effects of NO synthase inhibition with L‐NAME (100 µmol·L−1) on 5‐HT and acetylcholine responses. Superoxide anion production and mRNA levels of NOX‐1 and NOX‐4 were all increased. The superoxide anion scavenger tiron (1 mmol·L−1) reduced 5‐HT responses and increased acetylcholine responses only in vessels from mercury‐treated rats. In isolated hearts from mercury‐treated rats, coronary perfusion and diastolic pressure were unchanged, but developed isovolumetric systolic pressure was reduced. In these hearts, L‐NAME increased coronary perfusion pressure and diastolic pressure while it further reduced developed systolic pressure.

CONCLUSIONS AND IMPLICATIONS Chronic exposure to low doses of mercury promotes endothelial dysfunction of coronary arteries, as shown by decreased NO bioavailability induced by increased oxidative stress. These effects on coronary function increase resistance to flow, which under overload conditions might cause ventricular contraction and relaxation impairment. These findings provide further evidence that mercury, even at low doses, could be an environmental risk factor for cardiovascular disease.
A humanized monoclonal antibody targeting the β7 integrin selectively blocks intestinal homing of T lymphocytes
Authors: Stefanich EG , Danilenko DM , Wang H , O'Byrne S , Erickson R , Gelzleichter T , Hiraragi H , Chiu H , Ivelja S , Jeet S , Gadkari S , Hwang O , Fuh F , Looney C , Howell K , Albert V , Balazs M , Refino C , Fong S , Iyer S , Williams M
Published: January 2011

BACKGROUND AND PURPOSE rhuMAb Beta7 is a humanized anti‐human β7 monoclonal antibody currently in phase I in inflammatory bowel disease. rhuMAb Beta7 binds the β7 subunit of the integrins α4β7 and αEβ7, blocking interaction with their ligands. These integrins play key roles in immune cell homing to and retention in mucosal sites, and are associated with chronic inflammatory diseases of the gastrointestinal tract. The goal of this study was to evaluate the mucosal specificity of rhuMAb Beta7.

EXPERIMENTAL APPROACH We assessed the effect of murine anti‐Beta7 on lymphocyte homing in mouse models of autoimmune disease. We also compared the effect of rhuMAb Beta7 on circulating mucosal‐homing versus peripheral‐homing T cells in naïve non‐human primates.

KEY RESULTS In cynomolgus monkeys, occupancy of β7 integrin receptors by rhuMAb Beta7 correlated with an increase in circulating β7+ mucosal‐homing lymphocytes, with no apparent effect on levels of circulating β7‐ peripheral‐homing lymphocytes. rhuMAb Beta7 also inhibited lymphocyte homing to the inflamed colons of severe combined immunodeficient mice in CD45RBhigh CD4+ T‐cell transfer models. Consistent with a lack of effect on peripheral homing, in a mouse model of experimental autoimmune encephalomyelitis, anti‐β7 treatment resulted in no amelioration of CNS inflammation.

CONCLUSIONS AND IMPLICATIONS The results presented here suggest that rhuMAb Beta7 selectively blocks lymphocyte homing to the gastrointestinal tract without affecting lymphocyte trafficking to non‐mucosal tissues. rhuMAb Beta7 provides a targeted therapeutic approach with the potential for a more attractive benefit : risk ratio than currently available inflammatory bowel disease therapies.
Effects of rosiglitazone on the configuration of action potentials and ion currents in canine ventricular cells
Authors: Szentandrássy N , Harmati G , Bárándi L , Simkó J , Horváth B , Magyar J , Bányász T , Lőrincz I , Szebeni A , Kecskeméti V , Nánási PP
Published: January 2011

BACKGROUND AND PURPOSE In spite of its widespread clinical application, there is little information on the cellular cardiac effects of the antidiabetic drug rosiglitazone in larger experimental animals. In the present study therefore concentration‐dependent effects of rosiglitazone on action potential morphology and the underlying ion currents were studied in dog hearts.

EXPERIMENTAL APPROACH Standard microelectrode techniques, conventional whole cell patch clamp and action potential voltage clamp techniques were applied in enzymatically dispersed ventricular cells from dog hearts.

KEY RESULTS At concentrations ≥10 µM rosiglitazone decreased the amplitude of phase‐1 repolarization, reduced the maximum velocity of depolarization and caused depression of the plateau potential. These effects developed rapidly and were readily reversible upon washout. Rosiglitazone suppressed several transmembrane ion currents, concentration‐dependently, under conventional voltage clamp conditions and altered their kinetic properties. The EC50 value for this inhibition was 25.2 ± 2.7 µM for the transient outward K+ current (Ito), 72.3 ± 9.3 µM for the rapid delayed rectifier K+ current (IKr) and 82.5 ± 9.4 µM for the L‐type Ca2+ current (ICa) with Hill coefficients close to unity. The inward rectifier K+ current (IK1) was not affected by rosiglitazone up to concentrations of 100 µM. Suppression of Ito, IKr, and ICa was confirmed also under action potential voltage clamp conditions.

CONCLUSIONS AND IMPLICATIONS Alterations in the densities and kinetic properties of ion currents may carry serious pro‐arrhythmic risk in case of overdose with rosiglitazone, especially in patients having multiple cardiovascular risk factors, like elderly diabetic patients.

LINKED ARTICLE This article is commented on by Hancox, pp. 496–498 of this issue. To view this commentary visit http://dx.doi.org/10.1111/j.1476‐5381.2011.01281.x
Cytokine/anti‐cytokine therapy – novel treatments for asthma?
Authors: Hansbro Philip M , Kaiko Gerard E , Foster Paul S
Published: January 2011

Asthma is a chronic inflammatory disease of the airways and there are no preventions or cures. Inflammatory cells through the secretion of cytokines and pro‐inflammatory molecules are thought to play a critical role in pathogenesis. Type 2 CD4+ lymphocytes (Th2 cells) and their cytokines predominate in mild to moderate allergic asthma, whereas severe steroid‐resistant asthma has more of a mixed Th2/Th1 phenotype with a Th17 component. Other immune cells, particularly neutrophils, macrophages and dendritic cells, as well structural cells such as epithelial and airway smooth muscle cells also produce disease‐associated cytokines in asthma. Increased levels of these immune cells and cytokines have been identified in clinical samples and their potential role in disease demonstrated in studies using mouse models of asthma. Clinical trials with inhibitors of cytokines such as interleukin (IL)‐4, ‐5 and tumour necrosis factor‐α have had success in some studies but not others. This may reflect the design of the clinical trials, including treatments regimes and the patient population included in these studies. IL‐13, ‐9 and granulocyte‐macrophage colony‐stimulating factor are currently being evaluated in clinical trials or preclinically and the outcome of these studies is eagerly awaited. Roles for IL‐25, ‐33, thymic stromal lymphopoietin, interferon‐γ, IL‐17 and ‐27 in the regulation of asthma are just emerging, identifying new ways to treat inflammation. Careful interpretation of results from mouse studies will inform the development and application of therapeutic approaches for asthma. The most effective approaches may be combination therapies that suppress multiple cytokines and a range of redundant and disconnected pathways that separately contribute to asthma pathogenesis. Astute application of these approaches may eventually lead to the development of effective asthma therapeutics. Here we review the current state of knowledge in the field.

LINKED ARTICLES This article is part of a themed issue on Respiratory Pharmacology. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2011.163.issue‐1
Genetics of complex respiratory diseases: implications for pathophysiology and pharmacology studies
Authors: Obeidat Ma'en , Hall Ian P.
Published: January 2011

There has been a huge influx of data on the genetics and genomics of respiratory diseases in the last few years. Powered by large sample sizes from collaborations worldwide, recent genome‐wide association studies have convincingly implicated variants in different regions in the genome for association with complex respiratory traits. These new associations have the potential to offer invaluable insight into the pathophysiology of the normal and diseased respiratory system. The functional mechanisms underlying effects of both identified and novel variants will be the focus of research over the next few years. The identification of these mechanisms will not only increase our understanding of disease but may allow the development of new therapies to alleviate respiratory conditions. The implications of these approaches for studies of asthma and Chronic Obstructive Pulmonary Disease are covered in this review.

LINKED ARTICLES This article is part of a themed issue on Respiratory Pharmacology. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2011.163.issue‐1
The White (Male) Effect and Risk Perception: Can Equality Make a Difference?
Authors: Olofsson Anna , Rashid Saman
Published: January 2011

Previous research has shown that white males have a relatively low perception of risks, known as the “white male effect” (WME). Many of the explanations of this effect refer to the privileged position of this particular demographic group in society, adducing white males’ socio‐economic resources, sense of control, worldviews, etc. It can thus be argued that inequality leads women and ethnic minorities to have higher risk perception than men and the ethnic majority. Therefore, the aim of this study is to investigate the WME in a gender‐equal country, Sweden, to see if the pattern is similar to previous studies from the comparably less gender‐equal United States. The empirical analyses are based on a national survey (n= 1,472) on the perception of risk conducted in Sweden in the winter of 2005. The results show that in Sweden there is no significant difference between men and women in risk perception, while people with foreign backgrounds perceive risks higher than native people. The chief finding is that there is no WME in Sweden, which we concluded results from the relative equality between the sexes in the country. On the other hand, ethnicity serves as a marker of inequality and discrimination in Sweden. Consequently, ethnicity, in terms of foreign background, mediates inequality, resulting in high risk perception. Equality therefore seems to be a fruitful concept with which to examine differences in risk perception between groups in society, and we propose that the “societal inequality effect” is a more proper description than the “WME.”
Vicenza International Courses on hemodialysis: Educational events where science meets clinical practice
Authors: RONCO Claudio
Published: January 2011

International Vicenza Courses represent important educational events held yearly in the city of Palladio. Claudio Ronco organizes since 1982 international courses on peritoneal dialysis, hemodialysis and critical care nephrology. The faculty is outstanding and the content very informative and useful for beginners and for experts in the various fields. Every year the entire course is recorded in a DVD and the proceedings are available at the beginning of the course. Information can be obtained at http://www.vicenzanephrocourses.com.
Y‐Doped Bi2MoO6 Yellow Pigments for the Coloration of Plastics
Authors: Kumari Leela Sandhya , Gayathri Thozhuthungal Haridasan , Sameera Saithathul Fathimah , Rao Padala Prabhakar
Published: January 2011

Y‐doped Bi2MoO6 was synthesized by the conventional ceramic method in order to assess its potential as ceramic pigment. The optimized colorants were characterized for their structural as well as optical properties. The Bi(2−x)YxMoO6 materials absorb the visible and the ultraviolet light under 500 nm efficiently, which is originated in the transition from the valence band consisting of the O 2p orbitals to the conduction band derived from the primary Mo 4d orbitals in MoO6 octahedra and the secondary Bi 6p orbitals. The absorption edge of the pigments is red shifted by yttrium doping, and as a result, the pigments display colors from pale yellow to yellow. The effective yellow hue was observed for BiYMoO6, which imparted good coloration to plastics. The synthesized pigments were found to be interesting alternatives to existing toxic yellow pigments.
Sp3 transcription factor is crucial for transcriptional activation of the human NOX4 gene
Authors: Katsuyama Masato , Hirai Hideyo , Iwata Kazumi , Ibi Masakazu , Matsuno Kuniharu , Matsumoto Misaki , Yabe‐Nishimura Chihiro
Published: January 2011

NOX is the catalytic subunit of NADPH oxidase, the superoxide‐generating enzyme. Among several isoforms of NOX, NOX4 is abundantly expressed in various tissues. To clarify the mechanisms of constitutive and ubiquitous expression of NOX4, the promoter activities of the human NOX4 gene were analyzed by reporter assays. The 5’‐flanking and non‐coding regions of the human NOX4 gene are known to contain multiple GC bases. Among them, three GC‐boxes containing putative Sp/Klf‐binding sites, which were not found in rodent genes, were suggested to be essential for the basal expression of the NOX4 gene in SH‐SY5Y and HEK293 cells. Electrophoresis mobility shift assays demonstrated that Sp1 and Sp3 could bind to GC‐boxes at positions −239/−227 and +69/+81 in these cells. Chromatin immunoprecipitation assays showed that Sp1 and Sp3 could also bind to GC‐boxes at positions −239/−227 and +69/+81 in vivo. The promoter activity of the NOX4 gene was reduced in SH‐SY5Y and HEK293 cells by transfection of an anti‐Sp3 short hairpin RNA‐expression plasmid. Taken together, these results suggest that Sp3 plays a key role in the expression of NOX4 in various cell lineages in humans.
Combination of Testosterone and Vardenafil Increases Female Sexual Functioning in Sub-Primed Rats
Authors: Snoeren Eelke M.S. , Bovens Astrid , Refsgaard Louise K. , Westphal Koen G.C. , Waldinger Marcel D. , Olivier Berend , Oosting Ronald S.
Published: January 2011

Introduction

Hypoactive sexual desire disorder (HSDD) is a common problem in women and may have a negative impact on quality of life. A recent clinical study shows an increase in sexual drive of HSDD women after cotreatment of testosterone and vardenafil (phosphodiesterase type 5 inhibitor).

Aim

In this study, we investigated the effect of testosterone and vardenafil on sexual activity in female rats.

Main Outcome Measures

Proceptive (darts and hops), receptive (lordosis), and paced-mating (percentages after exits and contact-return latencies) behaviors were quantified.

Methods

Ovariectomized female rats, sub-primed with only estradiol and fully primed with estradiol and progesterone, were tested in a paced-mating sex test and sexual behaviors were quantified. The sub-primed rats are thought to model HSDD. The effect of testosterone (100 and 300 µg, subcutaneous [SC]) and vardenafil (10 mg/kg, per os [PO]) alone and testosterone (300 µg, SC) in combination with vardenafil (3 and 10 mg/kg, PO) were tested. We also studied the effects of testosterone (300 µg, SC) + intracerebroventricular (ICV) injections of vardenafil (25 and 50 µg) on sexual activity.

Results

No effect of testosterone and vardenafil alone was found, but cotreatment of testosterone and vardenafil (PO) caused a significant increase in proceptive and receptive behavior in the sub-primed female rats. Testosterone and vardenafil did not affect fully primed females. ICV administration of vardenafil combined with systemic testosterone, on the other hand, had no effect on sexual activity in both sub-primed and fully primed female rats.

Conclusions

We conclude that cotreatment of subcutaneous testosterone and oral vardenafil increase sexual activity in sub-primed female rats. Our data supports the human finding that combination treatment of testosterone and vardenafil could be used as a new treatment for women with HSDD.
Small cell lung cancer presenting with paraneoplastic limbic encephalitis
Authors: BOWYER Samantha , WEBB Suzanne , MILLWARD Michael , JASAS Kevin , BLACKER David , NOWAK Anna
Published: January 2011

We report two cases of the rare neurological paraneoplastic syndrome, limbic encephalitis, as the initial presentation of small cell lung cancer. The first case responded to treatment of the underlying malignancy, while the second required more acute treatment in the intensive care setting. In this case, initial treatment was with immunosuppression to achieve a degree of stability before the underlying malignancy could be treated. Both cases had significant improvement in neurological function. These cases highlight the importance of directed investigation to try and identify an underlying malignancy in patients in whom a diagnosis of limbic encephalitis is made, and the difficulty in managing such patients.
Corneal hysteresis in mucopolysaccharidosis I and VI
Authors: Fahnehjelm Kristina Teär , Chen Enping , Winiarski Jacek
Published: January 2011

Purpose:  High intraocular pressure (IOP) and glaucoma are often suspected in patients with mucopolysaccharidosis (MPS). To determine corneal hysteresis (CH) and IOP in children with mucopolysaccharidosis I‐Hurler (MPS I‐H) and MPS VI.

Methods:  Clinical measurements with ocular response analyzer (ORA).

Results:  In seven patients, five with MPS I‐H treated with stem cell transplantation (SCT), and two with MPS VI, one treated with SCT and the other with enzyme therapy, the IOP was examined with ORA. Ocular response analyzer measurements were made at a median age of 8.7 years in the patients with MPS I‐H and at a median age of 9.3 years in the patients with MPS VI. Earlier measurements had raised suspicion of high IOP in one patient. The ORA showed an increased CH and a falsely high IOP values in all 14 eyes. The recalculated IOPs were normal in all 14 eyes. Mild to severe corneal opacities were present in all 14 eyes. Optic disc areas, borders and cupping were clinically normal in the 12 of 14 eyes that were possible to examine. Severe corneal opacities hampered optic disc evaluation in the older patient with MPS VI. Three eyes in two patients had normal thickness of the retinal nerve fibre layer measured with scanning laser polarimetry with corneal compensation (GDx VCC). No patient was diagnosed or treated for glaucoma.

Conclusion:  The IOPs are often falsely high because of an increased resistance of the cornea and correlate to the extent of corneal clouding. In this small, cross‐sectional study, it appears that corneal resistance is directly correlated with corneal clouding, although a longitudinal study that evaluates resistance as the cornea clears with treatment would provide more direct evidence that corneal deposits are directly related to resistance. A correct measured IOP can avoid unnecessary medical or surgical hypotensive treatment.
Effect and mechanism of senkyunolide I as an anti-migraine compound from Ligusticum chuanxiong
Authors: Wang Yi-Han , Liang Shuang , Xu De-Sheng , Lin Xiao , He Chun-Yong , Feng Yi , Hong Yan-Long
Published: January 2011

Objective

To evaluate the analgesic and anti-migraine activities of senkyunolide I from Ligusticum chuanxiong.

Methods

Mice were orally administered various doses of senkyunolide I, and their pain levels were assessed in a hot-plate test and by application of acetic acid. The levels of 5-hydroxytryptamine (5-HT), 5-hydroxytryptophan (5-HTP), 5-hydroxyindoleacetic acid (5-HIAA), norepinephrine (NE) and dopamine (DA) in plasma and brain were assessed, and the monoamine turnover rates (5-HT/5-HTP, 5-HIAA/5-HT and NE/DA) were also calculated.

Results

Mice given senkyunolide I at 16 and 32 mg/kg had significantly elevated pain thresholds in the hot-plate test, and a dose of 32 mg/kg also reduced the number of abdominal writhing responses caused by acetic acid. Significant improvements were observed in the neurotransmitter levels of the drug-treated rats compared with the saline-administered controls. Compared to the rats with nitroglycerin-induced migraines, the levels of nitric oxide in the plasma and whole brain of rats given senkyunolide I were lower.

Conclusions

The present study suggests that senkyunolide I may be an active component of L. chuanxiong, traditionally used to treat migraine. The mechanism of pain relief in migraine model rats may be through adjusting the levels of monoamine neurotransmitters and their turnover rates, as well as decreasing nitric oxide levels in the blood and brain. Therefore, senkyunolide I may be developed as a potential treatment for migraine pain.
Experimental Investigations of Cycle-to-Cycle and Cylinder-to-Cylinder Variation of PCCI Combustion With High Injection Pressures
Authors: Juttu S. , Thipse S. S. , Mishra Praveen , Dhande N. B. , Marathe N. V. , Gajendra Babu M. K.
Published: January 2011

Recently HCCI combustion concept has gained the attention of industry and academia due to its potential to reduce NOx and PM emissions simultaneously from diesel engines. The HCCI concept also called as Partially-Premixed Charge Compression Ignition (PCCI) when heavy fuel like diesel is used as fuel. To achieve homogeneous mixture of diesel+air+residual gases, high injection pressures are required with fine atomization. The cycle-to-cycle and cylinder-to-cylinder variations in rail pressure and EGR ratio caused to variations in engine performance. In this study combustion stabilities and cycle-to-cycle variations of diesel engine operated in PCCI combustion mode were investigated at different fuel injection pressures on a 4-cylinder, 4-stroke diesel engine. The experiments were conducted with 500bar, 1000bar, 1500bar and 1800bar injection pressures at low load (IMEP = 2bar) and 50% load (IMEP = 8.5bar) at 2500 and 3000 rpm. No EGR was used at low load condition and 50% EGR was used at 50% load at all injection pressures. In-cylinder pressures of 100 cycles were recorded for each test conditions running with PCCI mode. Consequently, cycle-to-cycle variations of the maximum Rate of Heat Release (ROHRmax), maximum Total Heat Release (THRmax), IMEP and Pmax were analyzed and evaluated using Coefficient of Variation (COV) of each parameter. The significant difference in COV from cylinder-to-cylinder was observed at higher injection pressures. With high injection pressures, wide range of cycle-to-cycle variations were observed in engines operated in PCCI combustion mode limiting the injection pressure and operating range of engine. The results show that the injection pressure need to be optimized with respect to load to control the PCCI combustion at constant EGR ratio to minimize the cycle-to-cycle variations and also extend the operating range of PCCI mode.
Modeling the Effects of Intake Plenum Volume on the Performance of a Small Naturally Aspirated Restricted Engine
Authors: Hamilton Leonard J. , Cowart Jim S.
Published: January 2011

Intake tuning is a significant method of boosting performance by enhancing volumetric efficiency in a naturally aspirated engine. Elements of intake tuning can involve varying intake runner length, geometry and plenum shape and volume. Previous research has demonstrated the beneficial effects of increasing plenum volume on engine torque. This objective of this study was to evaluate the ability of analytical and two computer based models (simple and complex) to accurately predict the effects of varying plenum volume on steady state and transient engine performance for a small restricted spark ignition engine. The computer models were only moderately successful in characterizing steady state performance. The simple model matched torque peak locations but failed to adequately predict the advantageous effect of plenum volume on torque. The complex model more effectively simulated torque effects of plenum volume increase but did not adequately capture torque peak locations. Both models underestimated mid-range torque by up to 20%. Transient manifold filling was estimated well with both the complex computer model and analytical methods. Transient torque response differed by only 1–2 engine cycles and was also well predicted by the computer simulation.
Investigation of Running HCCI With Dual-Fuel in a Small Scale Engine
Authors: Wu Yuh-Yih , Tsai Hsien-Chi , Liu Ta-Chuan
Published: January 2011

Homogeneous charge compression ignition (HCCI) is a well-known technology that reduces the fuel consumption and exhaust emissions. This work implemented HCCI on a 150cc spark-ignition (SI) engine. The compression ratio of target engine was changed from 10.5 to 12.4 to enhance the compression temperature. In addition, a commercialized low-pressure injector was installed near the intake port for supplying fuel for HCCI operation. After the analysis of in-cylinder gas temperature, the dual fuel, with gasoline for the additive fuel and kerosene as the main fuel, was investigated in the small scale target engine. Experiments were executed through various excess air ratios, different gasoline additive ratios and then extension of engine load. Two-stage heat release, which provides energy to heat up the mixture during the compression stroke, was observed from HCCI combustion with kerosene fuel. The maximum rate of pressure rise (MRPR) could be reduced by increasing gasoline additive ratio of dual fuel without deteriorating the engine power output. By using the dual fuel method, the engine indicated mean effective pressure could be improved by a maximum percentage 23.9% and an average percentage 17.6% from just using kerosene fuel under the knocking limitation of MRPR equals to 4 bar/deg.
Efficiency Considerations of Later-Phased Low Temperature Diesel Combustion
Authors: Knight Bryan M. , Bittle Joshua A. , Jacobs Timothy J.
Published: January 2011

Low temperature diesel combustion offers an opportunity to simultaneously and substantially reduce exhaust nitrogen oxides and particulate matter emissions. One issue that remains an area of investigation is the improvement of engine efficiency (i.e., specific fuel consumption) for the novel mode of combustion. The objective of this article is to assess the several parameters (i.e., friction, pumping work, combustion phasing, heat transfer rate, and combustion efficiency) that affect the brake fuel conversion efficiencies of a medium-duty diesel engine as its combustion mode is transitioned from conventional to low temperature. The analysis reveals that, in this study’s development of low temperature combustion, late combustion phasing is the primary factor causing a decrease in brake fuel conversion efficiency. To enable low temperature combustion, combustion is retarded to a point where peak rate of heat release occurs at around 24° after top dead center. Such late combustion misses the opportunity to utilize the full expansion stroke of the piston. Although exhaust hydrocarbon and carbon monoxide concentrations increase as a result of the later-phased low temperature combustion mode, combustion efficiency only drops to around 90%. This decrease in combustion efficiency accounts for only about 18.7% of the corresponding decrease in brake fuel conversion efficiency (the balance decrease being caused by the later-phased combustion). Other factors that typically deteriorate brake fuel conversion efficiency (i.e., pumping work, friction, and rate of heat transfer) are all decreased with this study’s development of low temperature combustion. It is important to note that other implementations of low temperature combustion (e.g., advanced timing low temperature combustion) may not necessarily realize the same reductions in brake fuel conversion efficiency, or reductions may not necessarily be caused by the same dominant factors that are observed in this study’s later-phased low temperature combustion mode.
Ion Current, Combustion and Emission Characteristics in an Automotive Common Rail Diesel Engine
Authors: Henein Naeim A. , Badawy Tamer , Rai Nilesh , Bryzik Walter
Published: January 2011

Advanced electronically controlled diesel engines require a feedback signal to the ECU to adjust different operating parameters and meet demands for power, better fuel economy and low emissions. Different types of in-cylinder combustion sensors are being considered to produce this signal. This paper presents results of an experimental investigation on the characteristics of the ion current in an automotive diesel engine equipped with a common rail injection system. The engine is a 1.9 L, 4-cylinder, direct injection diesel engine. Experiments covered different engine loads and injection pressures. The relationships between the ion current, combustion parameters and engine out NO emissions and opacity are presented. The analysis of the experimental data identified possible sources of the ion current produced in diesel engines.
Comparative Test Results From a Virtual Multi-Cylinder Engine Transient Test System
Authors: Mangun Derek A. , Moskwa John J.
Published: January 2011

Researchers in the Powertrain Control Research Laboratory (PCRL) at the University of Wisconsin-Madison have developed and built a single-cylinder engine transient test system which accurately replicates the dynamic operation of a multi-cylinder engine. Using hardware-in-the-loop (HIL) simulation, the multi-cylinder engine’s transient (a) rotational dynamics, (b) intake gas dynamics, and (c) heat transfer dynamics are reproduced in real time using several patented subsystem designs. These subsystems produce the dynamic boundary conditions that would be present for a given cylinder within a multi-cylinder engine, based on either real-time model execution or predetermined command trajectories (e.g. measured data). In addition to replicating the effects of the virtual cylinders, the test system facilitates extension of the single-cylinder engine capabilities beyond typical steady-state regime limitations. The primary goals of this project are to retain the attributes of the single-cylinder engine that are most beneficial while overcoming the problems which cause the single-cylinder engine to operate differently than a multi-cylinder engine. This system represents a very unique test bed for controlling and understanding the influences of changes in the engine design and control, solves several of the problems associated with the operation of a single-cylinder engine, and allows rapid transient testing with slew rates in excess of 10,000 rpm/s. A virtual powertrain and vehicle model can be incorporated into this system so that standardized vehicle emission testing can be conducted with this single-cylinder engine system (e.g., FTP and other transient drive cycle tests). This paper reports the research findings of the performance effects achieved by including the multi-cylinder dynamic interactions during HIL simulation using only single-cylinder engine hardware. The target engine used for this study is the Ford 3.0 L V-6 SI engine, and both the multi- and single-cylinder engines are resident in the PCRL. By directly comparing the operation of this virtual multi-cylinder transient test system with its actual multi-cylinder engine counterpart, the influences of the included dynamics are documented. Evaluations include comparative data from rotational dynamics and intake gas dynamics, as well as the ability to control heat transfer dynamics and conduct exhaust emission testing.
Changes in Section XI: Repairs and Replacements (2007 Through 2009)
Authors: Yonekawa Ronald A. , Gerlach Edward B.
Published: January 2011

Since the issue of the 2007 Edition of Section XI the changes have been of two categories. In the first category are a number of changes to paragraphs in IWA-4000 to fine tune and maintain the base code requirements. The second category contains some revisions and the issue of new code cases. In the text that follows, the code text revisions and revised and new cases (as issued in supplements 1–12) are described based on the Addenda in which their approved actions were issued.
ASME B31.3 End of Life Considerations: Corrosion, Mechanical Strength, and Small Bore Geometry
Authors: Williams Dennis K.
Published: January 2011

This paper discusses the prescribed requirements contained within the ASME B31.3 Process Piping Code that specifically address the considerations of the design corrosion allowance when coincidently taken into account with the mechanical strength requirements of the same. In particular, the most significant effects of the least favorable corrosion allowances in combination with the mechanical strength requirements of ASME B31.3 are prevalent in thin walled, small bore piping of minimal geometric properties associated with the calculation of component stresses in the longitudinal direction. Careful examination of ASME B31.3 paragraph 302.4 reveals that the minimum required thickness of a piping component include allowances for corrosion and when taken in conjunction with paragraph 302.4.1, which requires that when necessary, the wall thickness shall be increased to prevent overstress, damage, or collapse, due to superimposed loads from handling or other causes. The effects of the aforementioned Code requirements are addressed and examples are presented for small bore piping (nps 2″ and below) that lead to a proposed small bore piping criteria for consideration by piping specification engineers. Finally, the results of the evaluation of various combinations of corrosion allowance and mechanical strength requirements in terms of metal cross sectional area and section modulus are presented in tabular form that support the proposed small bore piping criteria.
Primary Creep Modeling Based on the Dependence of the Activation Energy on the Internal Stress
Authors: Esposito Luca , Bonora Nicola
Published: January 2011

In the high temperature component design the accumulation of creep strain during the primary stage cannot be ignored, since most the allowable design strain occurs in this stage, for which appropriate modelling is needed. In this work a mechanism based model for primary creep has been derived assuming that the creep rate in the transient regime can be given as a fraction of the steady state creep rate and as a function of the internal stress. Taking into account that the apparent activation energy varies with the internal stress and that the internal stress kinetic can be given as a function of strain, an exponential form of the creep rate vs creep strain has been obtained. The proposed model has been applied to high chromium steel P91 and the evolution of the decay constant and scaled activation volume with the applied stress has been determined.
Perforation Testing of a Titanium Alloy Target Using Hardened 4340 Steel Projectiles
Authors: Conway Jennifer M. , Ortiz Anthony R. , Jones Stanley E. , Acoff Viola , Bu Xiu
Published: January 2011

A perforation test, originally devised for composites and other materials that do not lend themselves easily to more conventional high strain rate testing procedures, is applied to a titanium alloy. In this test, cylindrical projectiles of hardened 4340 steel are launched from a smooth bore powder gun at velocities ranging from 50 m/s to 350 m/s. The projectiles have conical noses with pitch angles that vary from 90° to 30°. These projectiles impact the titanium alloy target at normal incidence and perforate it. After perforating the target, the projectiles are caught in a sand barrier. Based on the depth of penetration into the sand barrier, the residual velocity after perforation may be estimated. Knowing the impact velocity and the residual velocity, we can estimate the mechanical properties of the target, the ballistic limit, and the average strain rate. This valuable information is not usually available using other methods, especially for many unconventional target materials, such as composites and certain geologically based materials.
Outline of the JSME Mandatory Rules for Thermal Power Generation Facilities as the Harmonized Code in the Regulatory Requirements
Authors: Kimura Kazuhiro , Hamada Seiichi , Fujita Masaaki
Published: January 2011

The Japan Society of Mechanical Engineers (JSME) issued the latest edition of Rules on Thermal Power Generation Facilities (JSME S TA1, TA2-2008) and the Mandatory Rules (JSME S TA0-2008) to satisfy the Japanese Electric Utility Industry Law and the Ministerial Ordinance (MO) No.51 of Ministry of Economy, Trade and Industry (METI). This Mandatory Rules were developed and described in form corresponding to the text of the regulatory Interpretations of MO No.51. Japan Electric Standards Committee (JESC) reviewed and evaluated these JSME Rules and proposed METI to accept the JSME Mandatory Rules as the harmonized code in MO No.51 of METI. These JSME Rules are basically equivalent to the ASME B & PV and Piping codes. In this paper, differences between JSME Rules and the ASME Rules were described to be helpful for the ASME Code users.