bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical and physical properties of slate from Britannia Cove, Newfoundland
Authors: Alam M.R. , Swamidas A.S.J. , Gale J. , Munaswamy K.
Published: July 2008

The experimental investigation described in this study was carried out to determine the physical and mechanical properties (elastic moduli, Poisson’s ratio, compressive and tensile strengths, hardness and plane strain fracture toughness) of slate quarried from Britannia Cove, Bonavista, Newfoundland, Canada. Microscopic observations were carried out to determine layers’ orientation and thickness and the grain boundaries. All tests were carried out according to American Society for Testing and Materials (ASTM) and International Society for Rock Mechanics (ISRM) procedures. The results obtained from this investigation were compared with those obtained from other published results for slate, mined from different parts of the world. It is seen that the present test results are compatible with other published results except for fracture toughness and direct tension tests. In fracture toughness tests, the calculated values using accepted empirical equations were much higher than the numerically computed values using finite element analysis (FEA). For the case of direct and indirect tension tests, the differences between our experimental values and previously published results were quite large.
Geotechnical characteristics of large slow, very slow, and extremely slow landslides
Authors: Glastonbury James , Fell Robin
Published: July 2008

Based on a study of 45 large slow-moving landslides, it is apparent that for a landslide to travel slowly after failure, the sliding is most likely to be active or reactivated, on a basal rupture surface at or close to residual strength. The likelihood of slow movement after failure is also increased when the inclination of the basal rupture surface is less than the residual friction angle. The slow-moving landslides are all of low rock-mass strength with varying degrees of disaggregation, or they possess soil strength. The influence of lateral margins on landslide restraint is generally small, with landslide movement typically controlled by fluctuations in piezometric pressure. The most commonly observed slow large landslides are mudslides and translational debris–rock slides, followed by particular forms of translational rock slides and internally sheared compound slides. Some mudslides display evidence of short periods of up to moderate velocities.
Shear strength characteristics of statically compacted unsaturated kaolin
Authors: Oh Won Taek , Garga Vinod K. , Vanapalli Sai K.
Published: July 2008

The shear strength characteristics of statically compacted unsaturated soil specimens of commercial kaolin (Ip= 15%) were determined using conventional triaxial shear testing apparatus extending total stress analysis. The testing program consists of two different types of confined compression shear strength tests on unsaturated soil specimens. In the first series of tests, the specimens were sheared immediately after the application of the confining pressure under undrained loading conditions. In the second series of tests, the specimens were first allowed to come to equilibrium with respect to volume change and suction value under the applied confining pressure and sheared at two different rates of strain. A psychrometer was used for measuring suction values. In addition, conventional consolidated undrained tests were also conducted on specimens that were saturated using the back pressure technique before shearing. Comparisons with respect to the shear strength behavior are provided for both saturated and unsaturated soil specimens. The shear strength contribution towards suction was determined from test results on unsaturated soil specimens extending state variable approach in terms of total stresses. Discussion is presented to understand the influence of the following factors (i) suction, (ii) confining pressure, and (iii) rate of strain on the shear strength.
New xanthones from Cratoxylum cochinchinense
Authors: Laphookhieo Surat , Maneerat Wisanu , Buatip Taweesak , Syers J Keith
Published: July 2008

Investigation of the dried fruits of Cratoxylum cochinchinense led to the isolation of three new oxygeranyl xanthones, cochinxanthone A-C (1–3), together with seven known compounds (4–10). Their structures were characterized using spectroscopic methods including UV, IR, NMR, and MS.Key words: cochinxanthone A-C, Cratoxylum cochinchinense, Clusiaceae.
Bismuth-triflate-catalyzed Prins–Ritter reaction — An efficient synthesis of 4-amidotetrahydropyrans
Authors: Yadav J S , Subba Reddy B V , Chaya D N , Narayana Kumar GG KS
Published: July 2008

Bismuth(III) triflate is found to be an effective Lewis acid in catalyzing a three-component reaction of homoallylic alcohol, carbonyl compound, and nitrile at ambient temperature via the Prins–Ritter sequence to furnish 4-amidotetrahydropyrans in high yields, all with cis selectivity. Spirocyclic 4-amidotetrahydropyrans are obtained in case of cyclic ketones.Key words: Prins cyclization, bismuth(III) triflate, homoallyl alcohol, 4-amidotetrahydropyrans.
Identification of Streptomyces lividans proteins secreted by the twin-arginine translocation pathway following growth with different carbon sources
Authors: Guimond Julien , Morosoli Rolf
Published: July 2008

Genome-based signal peptide predictions classified Streptomyces coelicolor as the microorganism that secretes the most proteins through the twin-arginine translocation (Tat)-dependent secretion pathway. Availability of a ΔtatC mutant of the closely related strain Streptomyces lividans impaired Tat-dependent protein secretion and enabled identification of many extracellular proteins that are secreted via the Tat pathway. Proteomic techniques were applied to analyze proteins from the supernatants of log-phase cultures. Since the bacterial secretome depends mainly on the carbon sources available during growth, xylose, glucose, chitin, and soil extracts were used. A total of 63 proteins were identified, among which 7 were predicted by the TATscan program, and 20 were not predicted but contained a potential Tat signal motif. Thirteen proteins having no signal sequence could be co-transported by Tat-dependent proteins because the genes that encode these proteins are in close proximity in the genome. Finally, the presence of 23 proteins lacking signal peptides was difficult to explain. More secreted proteins could be identified as Tat substrates in varying carbon sources.
CaMK activation during exercise is required for histone hyperacetylation and MEF2A binding at the MEF2 site on theGlut4gene
Authors: Smith James A. H. , Kohn Tertius A. , Chetty Ashley K. , Ojuka Edward O.
Published: July 2008

The role of CaMK II in regulating GLUT4 expression in response to intermittent exercise was investigated. Wistar rats completed 5 × 17-min bouts of swimming after receiving 5 mg/kg KN93 (a CaMK II inhibitor), KN92 (an analog of KN93 that does not inhibit CaMK II), or an equivalent volume of vehicle. Triceps muscles that were harvested at 0, 6, or 18 h postexercise were assayed for 1) CaMK II phosphorylation by Western blot, 2) acetylation of histone H3 at the Glut4 MEF2 site by chromatin immunoprecipitation (ChIP) assay, 3) bound MEF2A at the Glut4 MEF2 cis-element by ChIP, and 4) GLUT4 expression by RT-PCR and Western blot. Compared with controls, exercise caused a twofold increase in CaMK II phosphorylation. Immunohistochemical stains indicated increased CaMK II phosphorylation in nuclear and perinuclear regions of the muscle fiber. Acetylation of histone H3 in the region surrounding the MEF2 binding site on the Glut4 gene and the amount of MEF2A that bind to the site increased approximately twofold postexercise. GLUT4 mRNA and protein increased ∼2.2- and 1.8-fold, respectively, after exercise. The exercise-induced increases in CaMK II phosphorylation, histone H3 acetylation, MEF2A binding, and GLUT4 expression were attenuated or abolished when KN93 was administered to rats prior to exercise. KN92 did not affect the increases in pCaMK II and GLUT4. These data support the hypothesis that CaMK II activation by exercise increases GLUT4 expression via increased accessibility of MEF2A to its cis-element on the gene.
Effects of calcitonin gene-related peptide on rat soleus muscle excitability: mechanisms and physiological significance
Authors: Macdonald W. A. , Nielsen O. B. , Clausen T.
Published: July 2008

Intense exercise causes a large loss of K+ from contracting muscles. The ensuing elevation of extracellular K+ ([K+]o) has been suggested to cause fatigue by depressing muscle fiber excitability. In isolated muscles, however, repeated contractions confer some protection against this effect of elevated K+. We hypothesize that this excitation-induced force-recovery is related to the release of the neuropeptide calcitonin gene-related peptide (CGRP), which stimulates the muscular Na+-K+ pumps. Using the specific CGRP antagonist CGRP-(8-37), we evaluated the role of CGRP in the excitation-induced force recovery and examined possible mechanisms. Intact rat soleus muscles were stimulated to evoke short tetani at regular intervals. Increasing extracellular K+ ([K+]o) from 4 to 11 mM decreased force to ∼20% of initial force ( P < 0.001). Addition of exogenous CGRP (10−9 M), release of endogenous CGRP with capsaicin, or repeated electrical stimulation recovered force to 50–70% of initial force ( P < 0.001). In all cases, force recovery could be almost completely suppressed by CGRP-(8-37). At 11 mM [K+]o, CGRP (10−8 M) did not alter resting membrane potential or conductance but significantly improved action potentials ( P < 0.001) and increased the proportion of excitable fibers from 32 to 70% ( P < 0.001). CGRP was shown to induce substantial force recovery with only modest Na+-K+ pump stimulation. We conclude that the excitation-induced force recovery is caused by a recovery of excitability, induced by local release of CGRP. The data suggest that the recovery of excitability partly was induced by Na+-K+ pump stimulation and partly by altering Na+ channel function.
Decrease in Levator Function in the Anophthalmic Orbit
Authors: Kim Nam Ju , Khwarg Sang In
Published: July 2008

Background/Aims: It has been argued that levator function in anophthalmic patients is reduced, but no detailed report on this topic has been issued. This study was undertaken to investigate measured levator function in anophthalmic patients, and to determine how measured values are related to prosthesis size. Methods: Unilateral anophthalmic patients with no significant ptosis, and no history of trauma or surgery to orbit or eyelid were recruited. Levator function was measured with patients wearing their prosthesis, test prosthesis of different heights, and no prosthesis. Results: Thirty-two patients were recruited. Levator function was found to be lower in anophthalmic orbits (10.43 ± 1.48 mm) than in contralateral normal orbits (12.74 ± 1.81 mm). Levator function was lower in anophthalmic orbits with any height or type of prosthesis than in contralateral normal orbits (paired t-test, p < 0.05). In the anophthalmic orbits, the levator functions were highest when patients wore a prosthesis of the proper height, and these functions reduced as the prostheses height reduced (linear regression, p < 0.05). Conclusion: Diminished levator function in an anophthalmic orbit doesn’t necessarily mean that levator muscle function is abnormal. When levator function is measured in an anophthalmic orbit, the fact that it is often underestimated should be taken into account.
Hemodynamic Assessment of Carotid Stenosis by Functional Magnetic Resonance Imaging
Authors: Jensen Ulf , Börsch Kathrin , Stingele Robert , Jansen Olav , Alfke Karsten
Published: July 2008

Background: Functional magnetic resonance imaging (fMRI) is a method usually used to identify cortical representations of cerebral functions. Some studies and case reports suggest that stenoses of the brain-supplying arteries influence the BOLD (blood-oxygenation-level-dependent) signal. The objective of this study was to find out whether the BOLD signal differs in the ipsilateral hemisphere of patients with hemodynamically relevant and those with irrelevant stenosis of the internal carotid artery (ICA) and if a successful treatment might have an influence on the BOLD signal. Methods: We included 10 patients with hemodynamically relevant stenosis in group 1; another 10 patients with hemodynamically irrelevant stenosis of the ICA were included in group 2. Patients underwent recanalization by either stenting or operation of the ICA. fMRI with a hand-tapping task was performed before and after treatment. Data were analyzed with ‘Statistical Parametric Mapping’ 2 for both hemispheres. An asymmetry index (AI, range 0–2) was calculated for the hand motor areas. Results: All data are given as means ± SD. The mean preinterventional AI in group 1 was 1.08 ± 0.87 and 0.30 ± 0.54 in group 2 (p = 0.029). The mean postinterventional AI was 0.32 ± 0.29 in group 1 and 0.25 ± 0.21 in group 2 (p = 0.599). Conclusion: fMRI is not only capable of delivering spatial information, but also of distinguishing a hemodynamically relevant from an irrelevant stenosis of the ICA.
Improved Detection of Intracerebral Hemorrhage with Transcranial Ultrasound Perfusion Imaging
Authors: Kern Rolf , Kablau Micha , Sallustio Fabrizio , Fatar Marc , Stroick Mark , Hennerici Michael G. , Meairs Stephen
Published: July 2008

Background: Ultrasound perfusion imaging (UPI) is a new approach for the assessment of brain perfusion. In contrast to the increasing experience with this method in patients with ischemic stroke, data on the value of UPI for the diagnosis of intracerebral hemorrhage (ICH) are lacking. Methods: We investigated 12 consecutive patients with sufficient temporal bone windows and a CT diagnosis of acute supratentorial ICH (basal ganglia n = 9 and lobar n = 3). Native transcranial B-mode ultrasound and UPI studies with echo contrast agents were performed on day 1 and on days 5–7 including volume measurements using the maximum extension on transverse and coronal ultrasound planes. Results: ICH was identified as hyperechogenic mass on B-mode ultrasound in 11/12 patients, but the correlation with CT volume measurements was poor (day 1: r = 0.4, 95% confidence interval, CI: –0.23–0.79; p = 0.1; follow-up: r = 0.58, 95% CI: 0.04–0.86; p = 0.21). Volume measurement was more precise using UPI with a significant correlation on day 1 (r = 0.8, 95% CI: 0.47–0.94; p < 0.001) and during the follow-up (r = 0.94, 95% CI: 0.81–0.98; p < 0.001). Using UPI the typical finding was a focal reduction of contrast agent arrival in the ICH core which led to better delineation of the lesion borders from adjacent tissue. Depiction of lobar ICH was difficult with ultrasound, and lesion sizes tended to be underestimated. Conclusions: This study supports earlier work demonstrating the usefulness of native transcranial ultrasound for the diagnosis of ICH. UPI further improves diagnostic reliability and allows very precise ICH volume measurements. If confirmed in larger studies, this approach may be useful for bedside monitoring of ICH progression and regression.
Strain Dyssynchrony Index Correlates With Improvement in Left Ventricular Volume After Cardiac Resynchronization Therapy Better Than Tissue Velocity Dyssynchrony Indexes
Authors: Miyazaki Chinami , Lin Grace , Powell Brian D. , Espinosa Raul E. , Bruce Charles J. , Miller Fletcher A. , Karon Barry L. , Rea Robert F. , Hayes David L. , Oh Jae K.
Published: July 2008

Background—

Various dyssynchrony indexes derived from tissue velocity and strain imaging have been proposed to predict the effectiveness of cardiac resynchronization therapy (CRT). We sought to compare the effect of CRT on dyssynchrony indexes derived by tissue velocity and strain and to determine which baseline intraventricular dyssynchrony parameters correlate with improvement in left ventricular volume after CRT.

Methods and Results—

Echocardiography with tissue Doppler imaging was performed in 45 patients with systolic heart failure at baseline, 1 day after CRT, and a median of 6 months after CRT. We calculated septal–lateral delay and anteroseptal–posterior delay and standard deviation of time to peak systolic velocity in the 12 basal and mid-left ventricular segments (Tv-SD). The standard deviation for time to peak strain in the 12 basal and mid-left ventricular segments (Tε-SD) was calculated as a strain-derived dyssynchrony index. None of the tissue velocity–derived dyssynchrony indexes improved after CRT (septal–lateral delay,
P
=0.39; anteroseptal–posterior delay,
P
=0.46; Tv-SD,
P
=0.30), whereas Tε-SD decreased significantly after CRT (
P
<0.001). Improvement in Tε-SD 1 day after CRT correlated with the reduction in end-systolic volume at follow-up (
r
=0.66;
P
<0.001). Baseline Tε-SD demonstrated significant correlation with the reduction of end-systolic volume at follow-up (
r
=0.57;
P
<0.001); however, baseline tissue velocity–derived dyssynchrony indexes failed to predict the effect of CRT.

Conclusions—

The strain-derived dyssynchrony index is a better measurement than the tissue velocity dyssynchrony index for monitoring changes in mechanical dyssynchrony after CRT and for predicting reduction in left ventricular volume after CRT.
Left Ventricular Diastolic Mechanical Dyssynchrony and Associated Clinical Outcomes in Children With Dilated Cardiomyopathy
Authors: Friedberg Mark K. , Roche Susan L. , Mohammed Arshiya F. , Balasingam Mervin , Atenafu Eshetu G. , Kantor Paul F.
Published: July 2008

Background—

We investigated diastolic mechanical dyssynchrony and its relation to clinical status in pediatric dilated cardiomyopathy (DCM).

Methods and Results—

We calculated a diastolic and systolic dyssynchrony index (standard deviation of time to peak tissue early diastolic/systolic velocity in 12 left ventricular segments) in 33 children with DCM and 46 control subjects. A threshold to diagnose diastolic dyssynchrony was determined, and cardiac function and clinical outcomes were compared between DCM patients with and without diastolic dyssynchrony. Left ventricular wall motion was more synchronized in diastole than in systole. The diastolic dyssynchrony index was significantly higher in children with DCM than in control subjects (28.1�18.1 versus 9.1�3.8 ms,
P
<0.0001). A 17-ms threshold indicated the presence of diastolic dyssynchrony. Patients who died or underwent transplantation had greater diastolic dyssynchrony (diastolic dyssynchrony index 37.9�20.5 versus 22.1�13.8 ms,
P
=0.01), and the rate of transplant-free survival appeared to be worse for DCM patients with diastolic dyssynchrony than for patients with synchronous DCM (hazard ratio 2.98,
P
=0.11; hazard ratio adjusted for disease duration 2.95,
P
=0.17).

Conclusions—

Left ventricular diastolic mechanical dyssynchrony is common in pediatric DCM, especially in patients who subsequently experience transplantation or death, and may be associated with a decreased length of transplantation-free survival.
The Global Conveyor Belt from a Southern Ocean Perspective
Authors: Iudicone Daniele , Speich Sabrina , Madec Gurvan , Blanke Bruno
Published: July 2008

Recent studies have proposed the Southern Ocean as the site of large water-mass transformations; other studies propose that this basin is among the main drivers for North Atlantic Deep Water (NADW) circulation. A modeling contribution toward understanding the role of this basin in the global thermohaline circulation can thus be of interest. In particular, key pathways and transformations associated with the thermohaline circulation in the Southern Ocean of an ice–ocean coupled model have been identified here through the extensive use of quantitative Lagrangian diagnostics. The model Southern Ocean is characterized by a shallow overturning circulation transforming 20 Sv (1 Sv ≡ 106 m3 s−1) of thermocline waters into mode waters and a deep overturning related to the formation of Antarctic Bottom Water. Mode and intermediate waters contribute to 80% of the upper branch of the overturning in the Atlantic Ocean north of 30°S. A net upwelling of 11.5 Sv of Circumpolar Deep Waters is simulated in the Southern Ocean. Antarctic Bottom Water upwells into deep layers in the Pacific basin, forming Circumpolar Deep Water and subsurface thermocline water. The Southern Ocean is a powerful consumer of NADW: about 40% of NADW net export was found to upwell in the Southern Ocean, and 40% is transformed into Antarctic Bottom Water. The upwelling occurs south of the Polar Front and mainly in the Indian and Pacific Ocean sectors. The transformation of NADW to lighter water occurs in two steps: vertical mixing at the base of the mixed layer first decreases the salinity of the deep water upwelling south of the Antarctic Circumpolar Current, followed by heat input by air–sea and diffusive fluxes to complete the transformation to mode and intermediate waters.
Seasonal Variations in the Circulation over the Middle Atlantic Bight Continental Shelf
Authors: Lentz Steven J.
Published: July 2008

Fits of an annual harmonic to depth-average along-shelf current time series longer than 200 days from 27 sites over the Middle Atlantic Bight (MAB) continental shelf have amplitudes of a few centimeters per second. These seasonal variations are forced by seasonal variations in the wind stress and the cross-shelf density gradient.

The component of wind stress that drives the along-shelf flow over most of the MAB mid- and outer shelf is oriented northeast–southwest, perpendicular to the major axis of the seasonal variation in the wind stress. Consequently, there is not a significant seasonal variation in the wind-driven along-shelf flow, except over the southern MAB shelf and the inner shelf of New England where the wind stress components forcing the along-shelf flow are north–south and east–west, respectively.

The seasonal variation in the residual along-shelf flow, after removing the wind-driven component, has an amplitude of a few centimeters per second with maximum southwestward flow in spring onshore of the 60-m isobath and autumn offshore of the 60-m isobath. The spring maximum onshore of the 60-m isobath is consistent with the maximum river discharges in spring enhancing cross-shelf salinity gradients. The autumn maximum offshore of the 60-m isobath and a steady phase increase with water depth offshore of Cape Cod are both consistent with the seasonal variation in the cross-shelf temperature gradient associated with the development and destruction of a near-bottom pool of cold water over the mid and outer shelf (“cold pool”) due to seasonal variations in surface heat flux and wind stress.
Loop Current and Deep Eddies
Authors: Oey L-Y.
Published: July 2008

In contrast to the Loop Current and rings, much less is known about deep eddies (deeper than 1000 m) of the Gulf of Mexico. In this paper, results from a high-resolution numerical model of the Gulf are analyzed to explain their origin and how they excite topographic Rossby waves (TRWs) that disperse energy to the northern slopes of the Gulf. It is shown that north of Campeche Bank is a fertile ground for the growth of deep cyclones by baroclinic instability of the Loop Current. The cyclones have horizontal (vertical) scales of about 100 km (1000∼2000 m) and swirl speeds ∼0.3 m s−1. The subsequent development of these cyclones consists of two modes, A and B. Mode-A cyclones evolve into the relatively well-known frontal eddies that propagate around the Loop Current. Mode-A cyclone can amplify off the west Florida slope and cause the Loop Current to develop a “neck” that sometimes leads to shedding of a ring; this process is shown to be the Loop Current’s dominant mode of upper-to-deep variability. Mode-B cyclones are “shed” and propagate west-northwestward at speeds of about 2–6 km day−1, often in concert with an expanding loop or a migrating ring. TRWs are produced through wave–eddy coupling originating primarily from the cyclone birthplace as well as from the mode-B cyclones, and second, but for longer periods of 20∼30 days only, also from the mode-A frontal eddies. The waves are “channeled” onto the northern slope by a deep ridge located over the lower slope. For very short periods (≲10 days), the forcing is a short distance to the south, which suggests that the TRWs are locally forced by features that have intruded upslope and that most likely have accompanied the Loop Current or a ring.
Seasonal Influence of Indonesian Throughflow in the Southwestern Indian Ocean
Authors: Zhou Lei , Murtugudde Raghu , Jochum Markus
Published: July 2008

The influence of the Indonesian Throughflow (ITF) on the dynamics and the thermodynamics in the southwestern Indian Ocean (SWIO) is studied by analyzing a forced ocean model simulation for the Indo-Pacific region. The warm ITF waters reach the subsurface SWIO from August to early December, with a detectable influence on weakening the vertical stratification and reducing the stability of the water column. As a dynamical consequence, baroclinic instabilities and oceanic intraseasonal variabilities (OISVs) are enhanced. The temporal and spatial scales of the OISVs are determined by the ITF-modified stratification. Thermodynamically, the ITF waters influence the subtle balance between the stratification and the mixing in the SWIO. As a result, from October to early December an unusual warm entrainment occurs, and the SSTs warm faster than just net surface heat flux–driven warming. In late December and January, the signature of the ITF is seen as a relatively slower warming of SSTs. A conceptual model for the processes by which the ITF impacts the SWIO is proposed.
Determining the Proportion of Children Too Heavy for Age-Appropriate Car Seats in a Practice-Based Research Network
Authors: Basco William T. , Hletko Paul J. , West Lynn , Darden Paul M.
Published: July 2008

Introduction more information is needed on how trends in childhood weight might influence legally compliant child safety seat (CSS) use.

Objective to determine the proportion of child passengers who cannot comply with one state's CSS law because of weight.

Method 6 practices in a practice-based research network provided data on patient demographics, heights, and weights. The authors calculated percentages of children above age-appropriate CSS weight cutoffs (20, 40, and 80 pounds, respectively) for the cohort below 6 years.

Results there were 717 participants below 6 years of age. Among all infants (<12 months), 16.4% weighed >20 pounds. Among children 12 months to <6 years old, 20% weighed >40 pounds. One weighed >80 pounds. There were no significant differences among racial groups. There was wide variation among practices, but differences did not achieve statistical significance.

Conclusion many children in this diverse cohort were too heavy to be compliant with the state CSS law.
Epidemiology of Playground Equipment-Related Injuries to Children in the United States, 1996–2005
Authors: Vollman David , Witsaman Rachel , Comstock R. Dawn , Smith Gary A.
Published: July 2008

The objective of this study is to describe the epidemiology of playground equipment-related injuries. This is a retrospective analysis of data for children 18 years old and younger from the National Electronic Injury Surveillance System of the United States Consumer Product Safety Commission for 1996 through 2005. There were an estimated 2 136 800 playground equipment-related injuries to children 18 years and younger treated in hospital emergency departments in the United States during the 10-year period. The leading mechanism of injury was falls (75.1%), followed by impact/striking (10.5%), cutting/ pinching/crushing (7.7%), entrapment/ entanglement (1.4%), trip/slip (1.1%), and other/ unknown (4.1%). The leading type of injury sustained by patients was a fracture (35.4%), followed by contusion/ abrasion (19.6%) and laceration (19.6%). The consistency of the large annual number of playground equipment-related injuries to children is evidence that more needs to be done to prevent these injuries. More research should be conducted to develop and implement arm fracture-specific criteria for surface performance.
Prurigo Nodularis in a 9-Year-Old Girl
Authors: Amer Ahdi , Fischer Howard
Published: July 2008

A 9-year-old African-American female with a known history of atopic dermatitis presented for evaluation of an intensely pruritic nodular rash on both upper and lower extremities, buttocks, and lower abdomen for more than 1 year. The patient had been treated with several medium-potency topical steroids and antipruritics without appreciable improvement. After considering and excluding other differential diagnoses, the diagnosis of prurigo nodularis (PN) in association with atopic dermatitis was made. Prurigo nodularis usually occurs in middle-aged and older persons and is rarely seen in the pediatric population. The onset of PN in the case presented is considerably earlier than what has been described in literature. The etiology of the disorder is unknown. The management of prurigo nodularis is usually challenging for both patients and treating physicians. Frequently, combinations of several medications or modalities are used in an attempt to control disease activity. Overall, PN is a benign condition in children, particularly when it is associated with atopic dermatitis. It does not increase mortality; however, it can cause significant morbidity in untreated patients.
A Strategic Use of the Communication Mix in the Destination Image-Formation Process
Authors: McCartney Glenn , Butler Richard , Bennett Marion
Published: July 2008

National tourist offices and tourism stakeholders are challenged to maintain and secure travel markets. Travelers are constantly bombarded with travel marketing messages. Compounding the challenge is a lack of research on effective, efficient, and optimal methods in convincing tourists to travel to a particular destination. To address this literature gap, a questionnaire survey on destination brand image research was conducted on outbound travelers from four major cities, examining their image perceptions of Macao and the degree of influence that various information sources had on destination selection. Results show that a communication mix strategy could be designed to more effectively manage tourist destination image perceptions. A cross-tabulation of the data revealed that the information sources affecting travel destination choice had varying levels of influence. A “Communication Effectiveness Grid” (CEG) was conceptualized from the research with quadrants indicating marketing resource effectiveness. The CEG has significant implications for destinations with limited budgets wishing to influence travelers.
Effects of Erdosteine on Acetaminophen-induced Hepatotoxicity in Rats
Authors: Kuvandik Guven , Duru Mehmet , Nacar Ahmet , Yonden Zafer , Helvaci Rami , Koc Ahmet , Kozlu Tolunay , Kaya Hasan , Sogüt Sadik
Published: July 2008

We investigated the effects of erdosteine on acetaminophen (APAP)-induced hepatotoxicity in rats. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), AST (aspartate aminotransferase), and ALT (alanine transaminase) activities, and malonyldialdehyde (MDA) and nitric oxide levels as oxidant/antioxidant biochemical parameters were investigated with light microscopic evaluation in adult female Wistar Albino rats. APAP administration produced a decrease in hepatic SOD, CAT, and GSH-Px activities, and coadministration of erdosteine (150 and 300 mg/kg) resulted in increases in the activities. MDA and NO levels increased in the APAP group, and erdosteine treatments prevented these increases. Significant elevations in serum AST and ALT levels were observed in the APAP group, and when erdosteine and APAP were coadministered, their serum levels were close to those in the control group. Light microscopic evaluation of livers showed that there were remarkable centrilobular (zone III) hepatic necrosis and mild to moderate sinusoidal congestion in the APAP group, whereas in the erdosteine group, cellular necrosis was minimal and the hepatocytes maintained a better morphology when compared to the APAP group. Erdosteine prevented APAP-induced liver injury and toxic side effects probably through the antioxidant and radical scavenging effects of erdosteine.
Ibogaine, an anti-addictive drug: pharmacology and time to go further in development. A narrative review
Authors: Mačiulaitis R , Kontrimavičiūtė V , Bressolle FMM , Briedis V
Published: July 2008

Ibogaine is an indole alkaloid derived from the bark of the root of the African shrub Tabernanthe iboga. Psychoactive properties of ibogaine have been known for decades. More recently, based on experimental data from animals and anectodal reports in human, it has been found that this drug has anti-addictive effects. Several patents were published between 1969 and 1995. The pharmacology of ibogaine is quite complex, affecting many different neurotransmitter systems simultaneously. However, the pharmacological targets underlying the physiological and psychological actions of ibogaine are not completely understood. Ibogaine is rapidly metabolized in the body in noribogaine. The purpose of this article was to review data from the literature concerning physicochemical properties, bio-analytical methods, and pharmacology of ibogaine; this article will be focused on the use of this drug as anti-addictive agent.
Students Advise Fortune 500 Company: Designing a Problem-Based Learning Community
Authors: Brzovic Kathy , Matz S. Irene
Published: July 2008

This article describes the process of planning and implementing a problem-based learning community. Business and communication students from a large university in the Western United States competed in teams to solve an authentic business problem posed by a Fortune 500 company. The company's willingness to adopt some of their recommendations testified to the professional quality of their final product. This experience gave students an opportunity to apply communication concepts to a business problem. They learned how to make vital connections between theory and practice and between shared knowledge and shared knowing. In the process, students grew personally and professionally.
All-cause mortality trends in Dikgale, rural South Africa, 1996—2003
Authors: Cook Ian , Alberts Marianne , Burger Sandy , Byass Peter
Published: July 2008

Aims: The Dikgale Demographic Surveillance System (DDSS) site, established in 1995, is one of three rural surveillance sites in South Africa. This paper describes detailed mortality patterns of a rural African population in the central region of Limpopo Province. Methods: These data were based on yearly household visits to collect data on vital events, covering 63, 873 person-years of observation over eight years. Results: Crude mortality was 7.5 per 1,000 person-years (females: 6.9, males: 8.1). Under-1 year and under-5 years mortality was 15.1 and 5.8 per 1,000 person-years, respectively. Life expectancy at birth was 64.3 years (females: 68.1, males: 60.0). For the two four-year periods (1996—9 and 2000—3) under-20 years mortality risk decreased (rate ratio=0.45, 95% CI: 0.25 to 0.80) while 20—49 years mortality risk increased (rate ratio=1.55, 95% CI: 1.10 to 2.20). Multivariate mortality risk for migrants remained relatively constant (0.71, 95% CI: 0.54 to 0.94) across the two four-year periods, but has increased 2.5-fold in all DDSS +50 year-old adults across the two four-year periods. Conclusions: The DDSS mortality estimates appear to have remained relatively constant while recent mortality estimates for the Agincourt Demographic and Health Surveillance System (ADHSS) site suggest that mortality risk is higher and life expectancy is lower in ADHSS residents. Moreover, DDSS mortality estimates are substantially more favourable compared with provincial and national mortality estimates.
The Importance and Challenge of Paying for Quality Nursing Care
Authors: Unruh Lynn Y. , Hassmiller Susan B. , Reinhard Susan C.
Published: July 2008

Historically, the economic value that nursing brings to the patient care process has not been recognized or quantified. Improving the quality of nursing care through work environment changes or increases in staffing is viewed by many as an added cost, but the benefits in terms of money saved through improved nursing satisfaction and patient outcomes are not considered. This article introduces nine articles that were originally presented at the Economics of Nursing Invitational Conference: Paying for Quality Nursing Care held at the Robert Wood Johnson Foundation in Princeton, New Jersey, June 13 and 14, 2007. Recommendations are to conduct research on the impact of policy and payment changes on the nursing workforce and quality of care and to correct the misalignment of socioeconomic and business case incentives for quality by payment systems and other changes.
The Business Case for Nursing in Long-Term Care
Authors: Horn Susan D.
Published: July 2008

Lower nurse staffing in hospitals has been associated with adverse patient outcomes; results in nursing homes (NHs) are less clear. We examined the association between nurses' direct care time and outcomes in long-stay NH residents and potential cost savings from decreased adverse outcomes versus additional wages for adequate nurse staffing. Data were from the National Pressure Ulcer Long-Term Care Study of 1,376 at-risk residents from 82 NHs. Primary data came from medical records. Hospital, pressure ulcer (PrU) treatment, and urinary tract infection (UTI) costs were from national statistics or cost-identification studies. Time horizon was 1 year. More registered nurse (RN) direct care time/resident/day was associated with fewer PrUs, hospitalizations, and UTIs. Annual net societal benefit was $3,191/resident/year in high-risk NH units with 30-40 min of RN time/resident/day versus units with <10 min. Thus, after controlling for important variables, more RN time/day was strongly associated with better outcomes and lower societal cost.
Traditional Masculinity and African American Men's Health-Related Attitudes and Behaviors
Authors: Wade Jay C.
Published: July 2008

This study investigates aspects of masculinity that may relate to African American men's health-related attitudes and behaviors. Two hundred and eight men completed measures of traditional masculinity ideology and health-related attitudes and behaviors. Results indicated that after accounting for participants' age, education, income, and employment status, traditional masculinity norms of self-reliance and aggression were associated with behaviors conducive to personal wellness and certain health-related psychological tendencies. Restrictive emotionality was associated with anxiety about one's health and the belief that one's health status is outside of one's personal control. Implications of the findings for the health-related attitudes and behaviors of African American men are discussed.
Review: Prevention of gastric cancer: When is treatment of Helicobacter pylori warranted?
Authors: Peek Richard M.
Published: July 2008

Chronic gastritis induced by Helicobacter pylori ( H. pylori) is the strongest known risk factor for adenocarcinoma of the distal stomach, yet the effects of bacterial eradication on carcinogenesis remain unclear. H. pylori isolates possess substantial genotypic diversity, which engenders differential host inflammatory responses that influence clinical outcome. H. pylori strains that possess the cag pathogenicity island and secrete a functional cytotoxin induce more severe gastric injury and further augment the risk for developing distal gastric cancer. Carcinogenesis is also influenced by host genetic diversity, particularly involving immune response genes such as interleukin-1β and tumor necrosis factor-α. Human trials and animal studies have indicated that eradication of H. pylori prior to the development of atrophic gastritis offers the best chance for prevention of gastric cancer. However, although the timing of intervention influences the magnitude of suppression of premalignant and neoplastic lesions, bacterial eradication, even in longstanding infections, is of clear benefit to the host. It is important to gain insight into the pathogenesis of H. pylori-induced gastritis and adenocarcinoma not only to develop more effective treatments for gastric cancer, but also because it might serve as a paradigm for the role of chronic inflammation in the genesis of other malignancies that arise within the gastrointestinal tract.
Erythroblastic islands: niches for erythropoiesis
Authors: Chasis Joel Anne , Mohandas Narla
Published: July 2008

Erythroblastic islands, the specialized niches in which erythroid precursors proliferate, differentiate, and enucleate, were first described 50 years ago by analysis of transmission electron micrographs of bone marrow. These hematopoietic subcompartments are composed of erythroblasts surrounding a central macrophage. A hiatus of several decades followed, during which the importance of erythroblastic islands remained unrecognized as erythroid progenitors were shown to possess an autonomous differentiation program with a capacity to complete terminal differentiation in vitro in the presence of erythropoietin but without macrophages. However, as the extent of proliferation, differentiation, and enucleation efficiency documented in vivo could not be recapitulated in vitro, a resurgence of interest in erythroid niches has emerged. We now have an increased molecular understanding of processes operating within erythroid niches, including cell-cell and cell-extracellular matrix adhesion, positive and negative regulatory feedback, and central macrophage function. These features of erythroblast islands represent important contributors to normal erythroid development, as well as altered erythropoiesis found in such diverse diseases as anemia of inflammation and chronic disease, myelodysplasia, thalassemia, and malarial anemia. Coupling of historical, current, and future insights will be essential to understand the tightly regulated production of red cells both in steady state and stress erythropoiesis.
Genomic characterisation, chromosomal assignment and in vivo localisation of the canine High Mobility Group A1 (HMGA1) gene
Authors: Beuing Claudia , Soller Jan T , Muth Michaela , Wagner Sigfried , Dolf Gaudenz , Schelling Claude , Richter Andreas , Willenbrock Saskia , Reimann-Berg Nicola , Winkler Susanne , Nolte Ingo , Bullerdiek Jorn , Escobar Hugo Murua
Published: July 2008

Background

The high mobility group A1 proteins (HMGA1a/HMGA1b) are highly conserved between mammalian species and widely described as participating in various cellular processes. By inducing DNA conformation changes the HMGA1 proteins indirectly influence the binding of various transcription factors and therefore effect the transcription regulation. In humans chromosomal aberrations affecting the HMGA1 gene locus on HSA 6p21 were described to be the cause for various benign mesenchymal tumours while high titres of HMGA1 proteins were shown to be associated with the neoplastic potential of various types of cancer. Interestingly, the absence of HMGA1 proteins was shown to cause insulin resistance and diabetes in humans and mice.

Due to the various similarities in biology and presentation of human and canine cancers the dog has joined the common rodent animal model for therapeutic and preclinical studies. Accordingly, the canine genome was sequenced completely twice but unfortunately this could not solve the structure of canine HMGA1 gene.

Results

Herein we report the characterisation of the genomic structure of the canine HMGA1 gene consisting of 7 exons and 6 introns spanning in total 9524 bp, the in vivo localisation of the HMGA1 protein to the nucleus, and a chromosomal assignment of the gene by FISH to CFA12q11. Additionally, we evaluated a described canine HMGA1 exon 6 SNP in 55 Dachshunds.

Conclusion

The performed characterisations will make comparative analyses of aberrations affecting the human and canine gene and proteins possible, thereby providing a basis for revealing mechanisms involved in HMGA1 related pathogenesis in both species.
Structural conservation versus functional divergence of maternally expressed microRNAs in the Dlk1/Gtl2 imprinting region
Authors: Kircher Martin , Bock Christoph , Paulsen Martina
Published: July 2008

Background

MicroRNAs play an important functional role in post-transcriptional gene regulation. One of the largest known microRNA clusters is located within the imprinted Dlk1/Gtl2 region on human chromosome 14 and mouse chromosome 12. This cluster contains more than 40 microRNA genes that are expressed only from the maternal chromosome in mouse.

Results

To shed light on the function of these microRNAs and possible crosstalk between microRNA-based gene regulation and genomic imprinting, we performed extensive in silico analyses of the microRNAs in this imprinted region and their predicted target genes.

Bioinformatic analysis reveals that these microRNAs are highly conserved in both human and mouse. Whereas the microRNA precursors at this locus mostly belong to large sequence families, the mature microRNAs sequences are highly divergent.

We developed a target gene prediction approach that combines three widely used prediction methods and achieved a sufficiently high prediction accuracy. Target gene sets predicted for individual microRNAs derived from the imprinted region show little overlap and do not differ significantly in their properties from target genes predicted for a group of randomly selected microRNAs. The target genes are enriched with long and GC-rich 3' UTR sequences and are preferentially annotated to development, regulation processes and cell communication. Furthermore, among all analyzed human and mouse genes, the predicted target genes are characterized by consistently higher expression levels in all tissues considered.

Conclusion

Our results suggest a complex evolutionary history for microRNA genes in this imprinted region, including an amplification of microRNA precursors in a mammalian ancestor, and a rapid subsequent divergence of the mature sequences. This produced a broad spectrum of target genes. Further, our analyses did not uncover a functional relation between imprinted gene regulation of this microRNA-encoding region, expression patterns or functions of predicted target genes. Specifically, our results indicate that these microRNAs do not regulate a particular set of genes. We conclude that these imprinted microRNAs do not regulate a particular set of genes. Rather, they seem to stabilize expression of a variety of genes, thereby being an integral part of the genome-wide microRNA gene regulatory network.