bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of strontium dioxide on the crystal structure and properties of tricalcium silicate
Authors: Wang Shoude , Li Guiqiang , Yin Chaonan , Lu Lingchao
Published: November 2012

Tricalcium silicate (C3S) doped with strontium dioxide was sintered at high temperature of 1600°C by solid reaction. The crystal structure and properties of C3S doped with strontium dioxide were investigated by means of chemical analysis, X-ray diffraction analysis, infrared analysis and hydration heat analysis. The experimental results show that pure C3S crystal has a triclinic crystalline form at room temperature. When doped strontium dioxide concentration is no more than 0·025 M, alite crystal is the same as the pure C3S crystalline form, whereas when doped strontium dioxide concentration is in the range 0·025–0·075 M, alite crystal is in monoclinic crystalline form. A small amount of strontium dioxide has the effect of decreasing the free lime content and promoting the formation of alite. Infrared analysis indicates that the addition of strontium dioxide can improve the crystal symmetry of alite. The hydration heat analysis shows that the addition of strontium dioxide can enhance hydration activity of alite and accelerate the hydration process.
Influence of carbonated additives on Portland cement hydration in chloride environment
Authors: Barauskas Irmantas , Kaminskas Rimvydas
Published: November 2012

This study investigated the influence of natural pozzolana (opoka) and limestone additives on the hydration of Portland cement and the effects of chloride ions on the formed hydrates. In the samples, 25% (by weight) of the Portland cement was replaced with additive. The specimens were then hardened for 28 days in water and then soaked in saturated sodium chloride (NaCl) solution for 3 months at 20°C. It is estimated that, under normal conditions, pozzolana and limestone additives accelerate the hydration of calcium silicates and initiate the formation of monocarboaluminate (CO32––AFm). Monocarboaluminate affected by NaCl becomes unstable and takes part in reactions producing Friedel's salt. More Cl−-containing compounds were formed in the samples with limestone than in the Portland cement samples after treatment in saturated NaCl solution. Meanwhile, pozzolana additive reduced the penetration of Cl– ions into the structure of Portland cement hydrates and impeded the formation of aluminium chloride hydrates.
Stimulated decomposition in peat for engineering applications
Authors: Pichan Som P. , O'Kelly Brendan C.
Published: November 2012

Peat deposits are highly compressible, undergoing significant long-term settlement, particularly for fibrous peat. Since decomposition of organic matter can have a significant effect on compression behaviour, the ability to artificially stimulate and pre-decompose a bearing peat stratum prior to the main construction works may mitigate against increased compression rates reported to occur over the design life. This paper presents a feasibility trial of a technique that accelerates the decomposition process in peat prior to entering into full laboratory and field testing. The main decomposition limiting factors of pH and carbon:nitrogen (C:N) ratio are adjusted by adding sufficient amounts of basic and nitrogenous materials. The proposed technique can be tailored for specific peat deposits and can also be achieved in a more sustainable manner. In the trial on moderately decomposed fibrous Sphagnum peat, different peat blends were prepared using additives of peat pulverised fuel ash (PPFA) and urea. Optimum C:N ratio and pH for decomposition were achieved by adding ∼21 kg PPFA and ∼1·5 kg urea per cubic metre of wet peat. The availability of natural decomposers in the peat was also confirmed pre- and post-treatment using a plate count technique, with measured microorganism populations of the order of 105colony-forming units (CFU)/g dry peat.
Thin ECC overlay systems for rehabilitation of rigid concrete pavements
Authors: Yucel Hasan Erhan , Jashami Hisham , Sahmaran Mustafa , Guler Murat , Yaman Ismail Ozgur
Published: November 2012

The use of rigid overlays has become increasingly popular. The main purpose of an overlay is to extend the service life of the structure and increase the structural performance and durability of a wearing surface. The superior ductility and durability characteristics of engineered cementitious composites (ECC) suggest that they could be used as an attractive alternative to conventional concrete overlay materials. In this study, the performance of ECC overlay designed at different thicknesses is investigated by laboratory experiments. Micro-silica concrete (MSC), generally used as an overlay material, is also prepared as a control mixture. The test results show that, for the same geometry and loading conditions, layered ECC beams have significantly increased both load-carrying capacity and deformability, and show better crack width control in comparison with MSC composite beams. As the overlay material, ECC is also found to be effective in eliminating the reflective cracking and delamination failure in repaired systems.
Use of non-destructive techniques in Chinese traditional timber structures
Authors: Che Ailan , Ge Xiurun , Li Yueming
Published: November 2012

The study of structural damage detection in ancient Chinese timber buildings is very important in the protection and rehabilitation of the ancient architectural culture. The purpose of structural damage detection is to identify the location and grade of structural damage based on the variation in characteristics of the structure, which is dependent on positioning techniques and quantitative analysis of structural damage detection. These elements are studied thoroughly by introducing microtremor measurements and using the finite-element method. Multi-domain microtremor measurements are performed to detect the tilting and twisting of the structure. From the observational data, the natural frequencies and vibration modes of the structure are evaluated, and these are compared with numerical results. In the numerical analysis, the changes in dynamic characteristics of the structure, such as natural frequencies and natural modes, are obtained, with special attention paid to the characteristics of brackets. Comparing the natural frequencies and natural modes from microtremor measurements with those from three-dimensional numerical analysis, the location and form of the damage is qualitatively delimited. Through continued reduction of the stiffness of the damaged layer in different directions, until the natural frequencies and natural modes from the simulation are shown to be consistent with those of the microtremor measurements, the severity of damage to the structure is quantitatively evaluated.
Performance of 45-year-old corroded prestressed concrete beams
Authors: Pape Torill M. , Melchers Robert E.
Published: November 2012

The design of prestressed concrete bridge beams usually assumes that the full capacity of the tendons can be achieved under ultimate load, based on the assumption of sufficient deformation capacity of the prestressing wires. Whether this is achieved also in older bridges is of increasing interest in remaining-life assessments since, especially in aggressive marine environments, corrosion of steel is known to cause loss of wire ductility. Results are reported herein of load tests to destruction for three full-sized and deteriorated prestressed concrete bridge beams recovered from a 45-year-old bridge exposed to an aggressive marine environment. The two beams with the greatest superficial deterioration showed progressive and premature failure of the prestressing wires. The beam with little superficial deterioration also showed progressive failure and failed to reach the ultimate load capacity based on current design theory and actual material properties. Possible reasons for the observed behaviour and the practical implications are discussed.
Seismic retrofit of non-ductile reinforced concrete frames with chevron braces
Authors: Ozcelik Ramazan , Binici Baris , Akpinar Ugur
Published: November 2012

The use of chevron braces for seismic strengthening of existing non-ductile reinforced concrete frames was investigated experimentally and numerically. Five strengthened and two as-built reference portal frame specimens were tested under a constant gravity load and increasing cyclic lateral displacement excursions. The test results indicated that steel brace retrofitting increased the lateral stiffness, strength and energy dissipation capacity significantly. Specimens strengthened with square hollow sections experienced significant strength degradation upon brace buckling, but a lateral strength of about 3·5 times the strength of bare frames was maintained up to a drift ratio of about 2% in all strengthened specimens. Non-linear cyclic analysis was conducted to simulate the behaviour of the test specimens. A satisfactory agreement with estimated and observed load–deformation responses was observed. Using test observations and simulation results, the deformation capacity limits of chevron brace strengthened deficient frames were discussed. A parametric study was conducted to investigate the effectiveness of the chevron brace retrofitting for different brace sizes and column axial loads. Finally, a non-linear time history analysis was performed for a building frame of a deficient existing four-storey three-bay reinforced concrete structure by using two chevron brace sections in this study.
Modelling the spatial variation of road safety in Greece
Authors: Papadimitriou Eleonora , Eksler Vojtech , Yannis George , Lassarre Sylvain
Published: November 2012

The analysis of spatial dependences among road safety outcomes (road accidents and fatalities) has received increased attention in recent research with interesting findings at national or European level. The objective of this research is the modelling of the spatial variation of road accidents and fatalities in Greece. Greece is selected as a country for which spatial effects have not been previously explored, and also as a country presenting some spatial particularity (i.e. loose spatial structure with many clusters of islands), making such an analysis interesting. For that purpose, Nuts-3 road accident and fatalities risk rates are used for the development of conditional auto-regressive (Car) and Car-convolution spatial models. Moreover, two types of neighbourhood structures of regional road safety data are tested: a basic structure defined according to the road connections between counties and an extended structure defined on the basis of both road and ferry connections between counties. The results suggest that the basic spatial structure accounts for an important part of the variation in road accident rates in the Greek counties, revealing a pattern of risk increase from northern to southern Greece. Spatial effects are also identifiable when considering the extended spatial structure, without, however explaining a larger part of the overall variation compared to the basic structure. Finally, it is shown that the effect of a key explanatory variable of road safety in Greece, namely alcohol enforcement, would have been quite overestimated if spatial effects were not taken into account in the models.
Physical properties of multi-layer seal surfacing in Turkey
Authors: Terzi Serdal , Karaşahin Mustafa , Saltan Mehmet , Yilmaz Altan , Saplioğlu Meltem , Ertem Selcan , Özgüngördü Meriç , Taciroğlu Murat V.
Published: November 2012

Seal surfacing is frequently used on low-volume roads throughout the world. However, seal surfacing is also used on high-volume roads in Turkey. Seventy-nine percent of the total amount of road length for which the General Directorate of Turkish Highways is responsible is coated with seal surfacing, and most of the 15 000 km of divided roads under construction are projected to be seal-surfacing roads. For this reason, there is a need for more information about seal surfacing. Within the context of the present study, the state and provincial roads located in the south-western part of Anatolia were investigated and core samples were taken from multi-layered seal-surfacing pavements. The core samples were fixed in size to match the standard Marshall sample size. The physical characteristics were defined by carrying out unit weight tests, ultrasound tests and Marshall stability tests. Skid resistance tests were performed around the core extraction areas on the road surfaces. In order to conduct analyses of the binder portions and the aggregate portions of the core samples, binder was extracted from the core samples through the use of a centrifuge extractor. As a consequence, attempts were made to determine the physical characteristics and actual conditions of multi-layer seal surfacing. In conclusion, it emerged that in the case of both building techniques and material characteristics, seal surfacing differs from hot mix asphalt. However, multi-layer seal surfacing demonstrates properties that are similar to those of hot mix asphalt. It must be taken into consideration that there are significant differences in stability and yield values.
Study on service level evaluation of Beijing urban expressway, China
Authors: Wang Zhuo , Dong Xiao-ting , Dong Hong-hui , Jia Li-min , Qin Yong
Published: November 2012

The service level of a road is an indicator which measures the traffic flow operating condition and service quality experienced by drivers and passengers. In the present study, the service level classification and evaluation of Beijing urban expressway, China were established on the basis of three parameters of traffic flow. As a result of the interference of the external environment, some abnormal data existed in the raw data and so the multivariate quality control method and the time-related method were used initially to screen and recover them. Next the service level classification was set up on the basis of the Delphi method and the semi-supervised clustering method, and finally a BP neural network was used to evaluate the service level. This study of the service level of Beijing urban expressway, China provides a scientific basis for traffic management and plays an important role in the traffic decision-making.
HDM-4 adaptation for strategic analysis of UK local roads
Authors: Odoki Jennaro B. , Anyala Michael , Bunting Edward
Published: November 2012

The UK Department for Transport is concerned to know that long-term investments in maintenance of local roads are contributing optimally to the UK economy, and that road maintenance funds are distributed equitably and provide value for money for the taxpayer. This quest can be accomplished by using decision support tools capable of predicting the long-term performance and costs of maintenance of the UK local road network. This paper describes the development of the World Bank's highway development and management model HDM-4 for use by the Department for Transport at the strategic level. This involved adaptation and calibration of HDM-4 to accurately model pavement performance and road user effects in England, linking HDM-4 with the existing database system used by the Department for Transport in order to facilitate strategic level analysis and investigation of road investment choices, and conducting a trial strategy analysis of the English local road network to quantify long-term maintenance needs and assess the effects of different maintenance funding levels on the condition of the network and costs to road users. The strategic analysis derived optimal capital and recurrent maintenance needs to clear existing maintenance backlogs and thereafter keep the road network in good condition on a sustainable basis.
Three-dimensional modelling of high speed ballasted railway tracks
Authors: Banimahd Meysam , Woodward Peter , Kennedy Justin , Medero Gabriela
Published: November 2012

In the present paper, a three-dimensional dynamic railway finite-element model, is utilised to study the geotechnical performance of high speed railway tracks. This model takes into account many of the railway track components such as multi-layered ballast and subgrade, nonlinearity in resilient behaviour of the sub-soil, and track–train interaction. Different features of the developed model are briefly presented. The effects of train speed, ballast and subgrade stiffness, and nonlinearity of the soil behaviour are then investigated. The results of the numerical simulations regarding the track response and required maintenance levels, in terms of the stress and vibration level experienced by the ballast and subgrade are also discussed and compared to site measurements. Track design methods are also reviewed, and a design method based on the dynamic finite-element analysis is proposed and discussed, which aims at minimising railway track maintenance levels by protecting the subgrade from dynamic ground amplification for speeds approaching the Rayleigh wave velocity, and also aims at minimising ballast maintenance by setting a maximum ballast particle velocity.
The Effect of Esthetic Crown Lengthening on Perceptions of a Patient's Attractiveness, Friendliness, Trustworthiness, Intelligence, and Self‐Confidence
Authors: Malkinson Sam , Waldrop Thomas C. , Gunsolley John C. , Lanning Sharon K. , Sabatini Robert
Published: November 2012

Background: Smile esthetics have been shown to play a major role in the perception of whether a person is attractive, and whether they are perceived as friendly, trustworthy, intelligent, and self‐confident. A proposed major determinant of the esthetics of a smile is the amount of gingival display, which can be excessive in cases of altered passive eruption. The aim of this study is to see whether altering the amount of gingival display of patients would affect dental professionals’ and laypersons’ perceptions of the aforementioned social parameters.

Methods: Patients were identified as having altered passive eruption and excessive gingival display. Smiling “control” photographs were taken and then digitally altered so as to lengthen the teeth and thus reduce the amount of gingival display. These became the “test” photographs. The control and test photographs were shown in random order. The control group of evaluators consisted of senior dental students, and the test group of evaluators comprised students who had no formal dental training. Groups were asked to rate, on a visual analog scale, each picture's attractiveness, friendliness, trustworthiness, intelligence, and self‐confidence.

Results: The test pictures with less gingival display were consistently and statistically significantly rated higher for all five social parameters than were their control counterparts (P <0.0001). When analyzed as an isolated effect, there were no statistically significant differences between the control group and the test group of evaluators when rating the pictures. Pictures depicting African Americans were judged to be more trustworthy (P = 0.0467) and self‐confident (P = 0.0490) than pictures depicting white individuals. Pictures depicting women were judged to be more trustworthy (P = 0.0159) and intelligent (P = 0.0329) than pictures depicting men. All the social parameters were positively and statistically significantly correlated with each other (P <0.0001).

Conclusions: Excessive gingival display did negatively affect how attractive a person's smile is judged to be. In addition, how friendly, trustworthy, intelligent, and self‐confident a person was perceived to be was inversely related to the amount of gingival display. Untrained laypeople were just as sensitive to these differences as senior dental students.
Innovative monitoring of combined sewer overflow (CSO) quality in the Liguori catchnment (Cosenza, Italy)
Authors: Piro Patrizia , Carbone Marco , Garofalo Giuseppina
Published: November 2012

Estimates of urban wet-weather flow pollutant loads are required to assess their impact on receiving waters and optimize wastewater treatment plant (WWTP) and combined sewer overflow (CSO) operations. In particular, a quantitative characterization of flow quality by means of fairly accurate monitoring is required for developing a rational planning approach and preferential treatment strategies. The main aim of this paper is to examine the qualitative–quantitative characteristics of wet-weather flow in an urbanized test catchment in Cosenza, Italy, and to compare three studied water quality constituent concentrations (total suspended solids (TSS), total chemical oxygen demand (CODt) and filtered chemical oxygen demand (CODf)) obtained by laboratory analyses to those measured by a UV/Vis spectrometer (‘spectrolyzer scan’), which represents a most modern and efficient spectrometric instrument requiring little maintenance. The results of such comparisons indicated the feasibility of using in situ spectroscopy to provide fairly accurate concentrations of the constituents studied, particularly in the case of CODt and CODf.
Application of profluorescent nitroxides for measurements of oxidative capacity of combustion generated particles
Authors: Stevanovic S. , Ristovski Z.D. , Miljevic B. , Fairfull-Smith K.E. , Bottle S.E.
Published: November 2012

Oxidative stress caused by generation of free radicals and related reactive
oxygen species (ROS) at the sites of deposition has been proposed as a
mechanism for many of the adverse health outcomes associated with exposure to
particulate matter (PM). Recently, a new profluorescent nitroxide molecular
probe (BPEAnit) developed at QUT was applied in an entirely novel, rapid and
non-cell based assay for assessing the oxidative potential of particles (i.e.
potential of particles to induce oxidative stress). The technique was applied
on particles produced by several combustion sources, namely cigarette smoke,
diesel exhaust and wood smoke. One of the main findings from the initial
studies undertaken at QUT was that the oxidative potential per PM mass
significantly varies for different combustion sources as well as the type of
fuel used and combustion conditions. However, possibly the most important
finding from our studies was that there was a strong correlation between the
organic fraction of particles and the oxidative potential measured by the PFN
assay, which clearly highlights the importance of organic species in
particle-induced toxicity.
Adverse biological effects of Milan urban PM looking for suitable molecular markers of exposure
Authors: Mantecca Paride , Gualtieri Maurizio , Longhin Eleonora , Bestetti Giuseppina , Palestini Paola , Bolzacchini Ezio , Camatini Marina
Published: November 2012

The results presented summarise the ones obtained in the coordinated research
project Tosca, which extensively analysed the impact of Milan urban PM on
human health. The molecular markers of exposure and effects of seasonally and
size-fractionated PMs (summer and winter PM10, PM2.5) were investigated in in
vitro (human lung cell lines) and in vivo (mice) systems. The results
obtained by the analyses of cytotoxic, pro-inflammatory and genotoxic
parameters demonstrate that the biological responses are strongly dependent
upon the PM samples seasonal and dimensional variability, that ultimately
reflect their chemical composition and source. In fact summer PM10, enriched
in crustal elements and endotoxins, was the most cytotoxic and
pro-inflammatory fraction, while fine winter PMs induced genotoxic effects
and xenobiotic metabolizing enzymes (like CYP1B1) production, likely as a
consequence of the higher content in combustion derived particles reach in
PAHs and heavy toxic metals. These outcomes outline the need of a detailed
knowledge of the PMs physico-chemical composition on a local scale, coupled
with the biological hazard directly associated to PM exposure. Apparently
this is the only way allowing scientists and police-makers to establish the
proper relationships between the respirable PM quantity/quality and the
health outcomes described by clinicians and epidemiologists.
Retraction: A Field Experiment Comparing the Outcomes of Three Fraud Brainstorming Procedures: Nominal Group, Round Robin, and Open Discussion
Authors: Hunton James E. , Gold Anna
Published: November 2012

This article was originally published in 2010 in The Accounting Review 85 (3) 911–935; DOI: 10/2308/accr.2010.85.3.911.

The authors confirmed a misstatement in the article and were unable to provide supporting information requested by the editor and publisher. Accordingly, the article has been retracted.
The Peri-islet Basement Membrane, a Barrier to Infiltrating Leukocytes in Type 1 Diabetes in Mouse and Human
Authors: Korpos Éva , Kadri Nadir , Kappelhoff Reinhild , Wegner Jeannine , Overall Christopher M. , Weber Ekkehard , Holmberg Dan , Cardell Susanna , Sorokin Lydia
Published: November 2012

We provide the first comprehensive analysis of the extracellular matrix (ECM) composition of peri-islet capsules, composed of the peri-islet basement membrane (BM) and subjacent interstitial matrix (IM), in development of type 1 diabetes in NOD mice and in human type 1 diabetes. Our data demonstrate global loss of peri-islet BM and IM components only at sites of leukocyte infiltration into the islet. Stereological analyses reveal a correlation between incidence of insulitis and the number of islets showing loss of peri-islet BM versus islets with intact BMs, suggesting that leukocyte penetration of the peri-islet BM is a critical step. Protease- and protease inhibitor–specific microarray analyses (CLIP-CHIP) of laser-dissected leukocyte infiltrated and noninfiltrated pancreatic islets and confirmatory quantitative real time PCR and protein analyses identified cathepsin S, W, and C activity at sites of leukocyte penetration of the peri-islet BM in association with a macrophage subpopulation in NOD mice and human type 1 diabetic samples and, hence, potentially a novel therapeutic target specifically acting at the islet penetration stage. Interestingly, the peri-islet BM and underlying IM are reconstituted once inflammation subsides, indicating that the peri-islet BM-producing cells are not lost due to the inflammation, which has important ramifications to islet transplantation studies.
Intrahypothalamic Estradiol Regulates Glucose Metabolism via the Sympathetic Nervous System in Female Rats
Authors: Liu Ji , Bisschop Peter H. , Eggels Leslie , Foppen Ewout , Ackermans Mariette T. , Zhou Jiang-Ning , Fliers Eric , Kalsbeek Andries
Published: November 2012

Long-term reduced hypothalamic estrogen signaling leads to increased food intake and decreased locomotor activity and energy expenditure, and ultimately results in obesity and insulin resistance. In the current study, we aimed to determine the acute obesity-independent effects of hypothalamic estrogen signaling on glucose metabolism. We studied endogenous glucose production (EGP) and insulin sensitivity during selective modulation of systemic or intrahypothalamic estradiol (E2) signaling in rats 1 week after ovariectomy (OVX). OVX caused a 17% decrease in plasma glucose, which was completely restored by systemic E2. Likewise, the administration of E2 by microdialysis, either in the hypothalamic paraventricular nucleus (PVN) or in the ventromedial nucleus (VMH), restored plasma glucose. The infusion of an E2 antagonist via reverse microdialysis into the PVN or VMH attenuated the effect of systemic E2 on plasma glucose. Furthermore, E2 administration in the VMH, but not in the PVN, increased EGP and induced hepatic insulin resistance. E2 administration in both the PVN and the VMH resulted in peripheral insulin resistance. Finally, sympathetic, but not parasympathetic, hepatic denervation blunted the effect of E2 in the VMH on both EGP and hepatic insulin sensitivity. In conclusion, intrahypothalamic estrogen regulates peripheral and hepatic insulin sensitivity via sympathetic signaling to the liver.
Ceramides Contained in LDL Are Elevated in Type 2 Diabetes and Promote Inflammation and Skeletal Muscle Insulin Resistance
Authors: Boon James , Hoy Andrew J. , Stark Romana , Brown Russell D. , Meex Ruth C. , Henstridge Darren C. , Schenk Simon , Meikle Peter J. , Horowitz Jeffrey F. , Kingwell Bronwyn A. , Bruce Clinton R. , Watt Matthew J.
Published: November 2012

Dysregulated lipid metabolism and inflammation are linked to the development of insulin resistance in obesity, and the intracellular accumulation of the sphingolipid ceramide has been implicated in these processes. Here, we explored the role of circulating ceramide on the pathogenesis of insulin resistance. Ceramide transported in LDL is elevated in the plasma of obese patients with type 2 diabetes and correlated with insulin resistance but not with the degree of obesity. Treating cultured myotubes with LDL containing ceramide promoted ceramide accrual in cells and was accompanied by reduced insulin-stimulated glucose uptake, Akt phosphorylation, and GLUT4 translocation compared with LDL deficient in ceramide. LDL-ceramide induced a proinflammatory response in cultured macrophages via toll-like receptor–dependent and –independent mechanisms. Finally, infusing LDL-ceramide into lean mice reduced insulin-stimulated glucose uptake, and this was due to impaired insulin action specifically in skeletal muscle. These newly identified roles of LDL-ceramide suggest that strategies aimed at reducing hepatic ceramide production or reducing ceramide packaging into lipoproteins may improve skeletal muscle insulin action.
The Neuropathic Diabetic Foot Ulcer Microbiome Is Associated With Clinical Factors
Authors: Gardner Sue E. , Hillis Stephen L. , Heilmann Kris , Segre Julia A. , Grice Elizabeth A.
Published: November 2012

Nonhealing diabetic foot ulcers (DFUs) are a common and costly complication of diabetes. Microbial burden, or “bioburden,” is believed to underlie delayed healing, although little is known of those clinical factors that may influence microbial load, diversity, and/or pathogenicity. We profiled the microbiomes of neuropathic nonischemic DFUs without clinical evidence of infection in 52 individuals using high-throughput sequencing of the bacterial 16S ribosomal RNA gene. Comparatively, wound cultures, the standard diagnostic in the clinic, vastly underrepresent microbial load, microbial diversity, and the presence of potential pathogens. DFU microbiomes were heterogeneous, even in our tightly restricted study population, but partitioned into three clusters distinguished primarily by dominant bacteria and diversity. Ulcer depth was associated with ulcer cluster, positively correlated with abundance of anaerobic bacteria, and negatively correlated with abundance of Staphylococcus. Ulcer duration was positively correlated with bacterial diversity, species richness, and relative abundance of Proteobacteria, but was negatively correlated with relative abundance of Staphylococcus. Finally, poor glycemic control was associated with ulcer cluster, with poorest median glycemic control concentrating to Staphylococcus-rich and Streptococcus-rich ulcer clusters. Analyses of microbial community membership and structure may provide the most useful metrics in prospective studies to delineate problematic bioburden from benign colonization that can then be used to drive clinical treatment.
Insights Into the Molecular Mechanism for Type 2 Diabetes Susceptibility at the KCNQ1 Locus From Temporal Changes in Imprinting Status in Human Islets
Authors: Travers Mary E. , Mackay Deborah J.G. , Dekker Nitert Marloes , Morris Andrew P. , Lindgren Cecilia M. , Berry Andrew , Johnson Paul R. , Hanley Neil , Groop Leif C. , McCarthy Mark I. , Gloyn Anna L.
Published: November 2012

The molecular basis of type 2 diabetes predisposition at most established susceptibility loci remains poorly understood. KCNQ1 maps within the 11p15.5 imprinted domain, a region with an established role in congenital growth phenotypes. Variants intronic to KCNQ1 influence diabetes susceptibility when maternally inherited. By use of quantitative PCR and pyrosequencing of human adult islet and fetal pancreas samples, we investigated the imprinting status of regional transcripts and aimed to determine whether type 2 diabetes risk alleles influence regional DNA methylation and gene expression. The results demonstrate that gene expression patterns differ by developmental stage. CDKN1C showed monoallelic expression in both adult and fetal tissue, whereas PHLDA2, SLC22A18, and SLC22A18AS were biallelically expressed in both tissues. Temporal changes in imprinting were observed for KCNQ1 and KCNQ1OT1, with monoallelic expression in fetal tissues and biallelic expression in adult samples. Genotype at the type 2 diabetes risk variant rs2237895 influenced methylation levels of regulatory sequence in fetal pancreas but without demonstrable effects on gene expression. We demonstrate that CDKN1C, KCNQ1, and KCNQ1OT1 are most likely to mediate diabetes susceptibility at the KCNQ1 locus and identify temporal differences in imprinting status and methylation effects, suggesting that diabetes risk effects may be mediated in early development.
Association Between BMI Measured Within a Year After Diagnosis of Type 2 Diabetes and Mortality
Authors: Logue Jennifer , Walker Jeremy J. , Leese Graham , Lindsay Robert , McKnight John , Morris Andrew , Philip Sam , Wild Sarah , Sattar Naveed ,   on behalf of the Scottish Diabetes Research Network Epidemiology Group
Published: November 2012

OBJECTIVE

To describe the association of BMI with mortality in patients diagnosed with type 2 diabetes.

RESEARCH DESIGN AND METHODS

Using records of 106,640 patients in Scotland, we investigated the association between BMI recorded around the diagnosis of type 2 diabetes mellitus (T2DM) and mortality using Cox proportional hazards regression adjusted for age and smoking status, with BMI 25 to <30 kg/m2 as a referent group. Deaths within 2 years of BMI determination were excluded. Mean follow-up to death or the end of 2007 was 4.7 years.

RESULTS

A total of 9,631 deaths occurred between 2001 and 2007. Compared with the reference group, mortality risk was higher in patients with BMI 20 to <25 kg/m2 (hazard ratio 1.22 [95% CI 1.13–1.32] in men, 1.32 [1.22–1.44] in women) and patients with BMI ≥35 kg/m2 (for example, 1.70 [1.24–2.34] in men and 1.81 [1.46–2.24] in women for BMI 45 to <50 kg/m2). Vascular mortality was higher for each 5-kg/m2 increase in BMI >30 kg/m2 by 24% (15–35%) in men and 23% (14–32%) in women, but was lower below this threshold. The results were similar after further adjustment for HbA1c, year of diagnosis, lipids, blood pressure, and socioeconomic status.

CONCLUSIONS

Patients categorized as normal weight or obese with T2DM within a year of diagnosis of T2DM exhibit variably higher mortality outcomes compared with the overweight group, confirming a U-shaped association of BMI with mortality. Whether weight loss interventions reduce mortality in all T2DM patients requires study.
Altered Brain Microstructure Assessed by Diffusion Tensor Imaging in Patients With Diabetes and Gastrointestinal Symptoms
Authors: Frøkjær Jens Brøndum , Andersen Lars Wiuff , Brock Christina , Simrén Magnus , Ljungberg Maria , Søfteland Eirik , Dimcevski Georg , Yavarian Yousef , Gregersen Hans , Drewes Asbjørn Mohr
Published: November 2012

OBJECTIVE

In patients with long-standing diabetes mellitus (DM), there is increasing evidence for abnormal processing of gastrointestinal sensations in the central nervous system. Using magnetic resonance diffusion tensor imaging, we characterized brain microstructure in areas involved in visceral sensory processing and correlated these findings to clinical parameters.

RESEARCH DESIGN AND METHODS

Twenty-six patients with DM and gastrointestinal symptoms and 23 healthy control subjects were studied in a 3T scanner. The apparent diffusion coefficient (i.e., diffusivity of water) and fractional anisotropy (FA) (i.e., organization of fibers) were assessed in the “sensory matrix” (cingulate cortex, insula, prefrontal and secondary sensory cortex, amygdala, and corona radiata) and in corpus callosum.

RESULTS

Patients had decreased FA values compared with control subjects in 1) all areas (P = 0.025); 2) anterior (P < 0.001), mid- (P = 0.001), and posterior (P < 0.001) cingulate cortex; 3) prefrontal cortex gray matter (P < 0.001); 4) corona radiata (P < 0.001); 5) secondary sensory cortex (P = 0.008); and 6) anterior white matter (P = 0.045), anterior gray matter (P = 0.002), and posterior gray matter (P = 0.002) insula. No difference was found in corpus callosum (P > 0.05). The microstructural changes in some areas correlated with clinical parameters such as bloating (anterior insula), mental well-being (anterior insula, prefrontal cortex, and mid-cingulated and corona radiata), autonomic function based on electrocardiographic results (posterior insula and anterior cingulate), and presence of gastroparesis (anterior insula).

CONCLUSIONS

The findings of this explorative study indicate that microstructural changes of brain areas involved in visceral sensory processing are associated with autonomic dysfunction and therefore may be involved in the pathogenesis of gastrointestinal symptoms in DM patients.
Effect of Externally Cued Training on Dynamic Stability Control During the Sit-to-Stand Task in People With Parkinson Disease
Authors: Bhatt Tanvi , Yang Feng , Mak Margaret K.Y. , Hui-Chan Christina W-Y. , Pai Yi-Chung
Published: November 2012

Background

Previous studies have shown that people with Parkinson disease (PD) have difficulty performing the sit-to-stand task because of mobility and stability-related impairments. Despite its importance, literature on the quantification of dynamic stability control in people with PD during this task is limited.

Objective

The study objective was to examine differences in dynamic stability control between people with PD and people who were healthy and the extent to which externally cued training could improve such control during the sit-to-stand task in people with PD.

Design

This was a quasi-experimental controlled trial.

Methods

The performance of 21 people with PD was compared with that of 12 older adults who dwelled in the community. People with PD were randomly assigned to 2 groups: a group that did not receive training and a group that received audiovisually cued training (3 times per week for 4 weeks) for speeding up performance on the sit-to-stand task. Outcome measures recorded at baseline and after 4 weeks included center-of-mass position, center-of-mass velocity, and stability against either backward or forward balance loss (backward or forward stability) at seat-off and movement termination.

Results

Compared with people who were healthy, people with PD had greater backward stability resulting from a more anterior center-of-mass position at seat-off. This feature, combined with decreased forward stability at movement termination, increased their risk of forward balance loss at movement termination. After training, people with PD achieved greater backward stability through increased forward center-of-mass velocity at seat-off and reduced the likelihood of forward balance loss at movement termination through a posterior shift in the center-of-mass position.

Limitations

The study applied stability limits derived from adults who were healthy to people with PD, and the suggested impact on the risk of balance loss and falling is based on these theoretical stability limits.

Conclusions

For people with PD, postural stability against backward balance loss at task initiation was increased at the expense of possible forward balance loss at task termination. Task-specific training with preparatory audiovisual cues resulted in improved overall dynamic stability against both forward and backward balance loss.
Accuracy of Physical Therapists' Early Predictions of Upper-Limb Function in Hospital Stroke Units: The EPOS Study
Authors: Nijland Rinske H.M. , van Wegen Erwin E.H. , Harmeling-van der Wel Barbara C. , Kwakkel Gert ,   for the Early Prediction of Functional Outcome After Stroke (EPOS) Investigators
Published: November 2012

Background

Early prediction of outcome after stroke is becoming increasingly important, as most patients are discharged from hospital stroke units within several days after stroke.

Objectives

The primary purposes of this study were: (1) to determine the accuracy of physical therapists' predictions at hospital stroke units regarding upper-limb (UL) function, (2) to develop a computational prediction model (CPM), and (3) to compare the accuracy of physical therapists' and the CPM's predictions. Secondary objectives were to explore the impact of timing on the accuracy of the physical therapists' and CPM's predictions and to investigate the direction of the difference between predicted and observed outcomes. Finally, this study investigated whether the accuracy of physical therapists' predictions was affected by their experience in stroke rehabilitation.

Design

A prospective cohort study was conducted.

Methods

Physical therapists made predictions at 2 time points—within 72 hours after stroke onset (T72h) and at discharge from the hospital stroke unit (Tdischarge)—about UL function after 6 months in 3 categories, derived from the Action Research Arm Test. At the same time, clinical variables were measured to derive a CPM. The accuracy of the physical therapists' and CPM's predictions was evaluated by calculating Spearman rank correlation coefficients (rs) between predicted and observed outcomes.

Results

One hundred thirty-one patients and 20 physical therapists participated in the study. For the T72h assessment, the rs value between predicted and observed outcomes was .63 for the physical therapists' predictions and .75 for the CPM's predictions. For the Tdischarge assessment, the rs value for the physical therapists' predictions improved to .75, and the rs value for the CPM's predictions improved slightly to .76.

Limitations

Physical therapists administered a test battery every 3 days, which may have enhanced the accuracy of prediction.

Conclusions

The accuracy of the physical therapists' predictions at T72h was lower than that of the CPM's predictions. At Tdischarge, the physical therapists' and CPM's predictions are about equally accurate.
Solitary fibrous tumor of the scalp in a child
Authors: Rizk Tony , Awada Adnan , Sebaaly Amer , Hourani Roula
Published: November 2012

Solitary fibrous tumors (SFTs) are rare mesenchymal neoplasms that arise most commonly in the pleura but have been increasingly reported in extrapleural sites. The authors report the case of an SFT of the scalp that manifested as an enlarging scalp mass in a 2-year-old boy. The mass was surgically excised. Histological examination showed it to be composed of fusiform cells of variable cellularity with a central hyalinization zone. Immunohistochemical staining was positive for CD34 and negative for smooth muscle actin, S100 protein, desmin, and h-caldesmon. On 1-year follow-up, there was no recurrence of the mass. This case presented some diagnostic difficulty because of the wide range of possible diagnoses for a pediatric scalp mass; however, the distinct immunohistochemical profile helped to eliminate other more frequent fibrous tumors of the scalp.

The behavior of scalp SFTs is usually benign, but their course can be unpredictable, and recognition of these lesions is essential.
Iliac crest osteotomy to enhance exposure of the L4–5 interspace in minimally invasive lateral transpsoas interbody fusion: a cadaveric feasibility study
Authors: Fontes Ricardo B. V. , Traynelis Vincent C.
Published: November 2012

Object

Minimally invasive lateral transpsoas interbody fusion (LTIF) has emerged as a popular surgical technique in a remarkably short period of time. The authors' experience with this procedure and anecdotal evidence in the literature suggest that the iliac crest may occasionally prevent access to the L4–5 interspace during minimally invasive LTIF. The authors propose that removal of a minimal amount of ilium would allow for successful exposure of the L4–5 interspace in those cases with a “high-riding” iliac crest. Therefore, the objective of this study was to evaluate the feasibility of iliac osteotomy to enhance exposure of the L4–5 interspace for minimally invasive LTIF.

Methods

Twenty L4–5 minimally invasive LTIF procedures were performed on 10 cadavers. The L4–5 minimally invasive LTIFs were successfully completed in 13 of 20 attempts. In the remaining 7 cases, the iliac crest prevented perfect orthogonal access to the L4–5 interspace. An iliac osteotomy was performed until the tubular retractors could be perfectly aligned with the L4–5 interspace and minimally invasive LTIF accomplished. Anteroposterior fluoroscopic images were obtained before and after the osteotomies. The angle between the working instrument and the superior L-5 endplate was measured, as were craniocaudal displacement and the resected iliac area.

Results

Iliac osteotomy enabled completion of L4–5 minimally invasive LTIF in the 7 remaining cases. Iliac resection was minimal; an average of 4.92 cm2 of iliac surface was resected (range 2.08–8.27 cm2) to enable L4–5 access. Adequate working angles were maintained (average 3.3° change after resection) while significant caudal displacement of the tubular system was achieved (average 15.7 mm, range 5.2–27.6 mm).

Conclusions

A significant portion of patients may have a high-riding iliac crest and that may have had an impact on minimally invasive LTIF in this series; L4–5 cases are rare in relation to midlumbar spine cases in most minimally invasive LTIF patient series. Significant caudal displacement of the tubular system was achieved with minimal iliac osteotomy, ensuring access to the L4–5 interspace in all specimens while maintaining the minimally invasive philosophy behind minimally invasive LTIF.
Posterior dynamic stabilization in the treatment of degenerative lumbar stenosis: validity of its rationale
Authors: Ha Kee-Yong , Seo Jun-Yeong , Kwon Soon-Eok , Son Il-Nam , Kim Ki-Won , Kim Young-Hoon
Published: November 2012

Object

The authors undertook this study to investigate the validity of the rationale for posterior dynamic stabilization using the Device for Intervertebral Assisted Motion (DIAM) in the treatment of degenerative lumbar stenosis.

Methods

A cohort of 31 patients who underwent single-level decompression and DIAM placement for degenerative lumbar stenosis were followed up for at least 2 years and data pertaining to their cases were analyzed prospectively. Of these patients, 7 had retrolisthesis. Preoperative and postoperative plain lumbar radiographs obtained in all patients and CT images obtained in 14 patients were analyzed. Posterior disc heights; range of motion (ROM) of proximal, distal, and implant segments; lordotic angles of implant segments; percentage of retrolisthesis; and cross-sectional area and heights of intervertebral foramina on CT sagittal images were analyzed. Clinical outcomes were evaluated using visual analog scale scores and Oswestry Disability Index scores.

Results

The mean values for posterior disc height before surgery, at 1 week after surgery, and at the final follow-up visits were 6.4 ± 2.0 mm, 9.7 ± 2.8 mm, and 6.8 ± 2.5 mm, respectively. The mean lordotic angles at the implant levels before surgery, at 1 week after surgery, and at the final follow-up visits were 7.1° ± 3.3°, 4.1° ± 2.7°, and 7.0° ± 3.7°, respectively. No statistically significant difference was found between the preoperative values and values from final follow-up visits for posterior disc height and lordotic angles at implant levels (p = 0.17 and p = 0.10, respectively). There was no statistically significant difference between the preoperative and final follow-up visit values for intervertebral foramen cross-sectional area and heights on CT images. The ROMs of proximal and distal segments also showed no significant decrease (p = 0.98 and p = 0.92, respectively). However, the ROMs of implant segments decreased significantly (p = 0.02). The average 31.4-month improvement for all clinical outcome measures was significant (p < 0.001).

Conclusions

Based on radiological findings, the DIAM failed to show validity in terms of the rationale of indirect decompression, but it did restrict motion at the instrumented level without significant change in adjacent-segment ROM. The clinical condition of the patients, however, was improved, and improvement was maintained despite progressive loss of posterior disc height after surgery.