The pore structure of concrete has long been recognized as the key to a wide range of different mechanical, physical and chemical properties. However, the finite range of the different interrogation ...techniques for measuring pore structure has always limited our overall picture. In order to add to that picture, a high resolution, three-dimensional imaging technique called x-ray microtomography was employed as a way to link measurable microstructural features with alternate measurements of permeability in different concrete systems. Four different concretes were imaged at spatial resolutions between 1 and 4 microns. Using 3D image analysis techniques, the pore system was characterized by size distribution and connectivity. A parameter we termed "disconnected pore distance" correlated well with standard measures of chloride permeability.PUBLICATION ABSTRACT
Aims/hypothesis Acute or chronic exposure of beta cells to glucose, palmitic acid or pro-inflammatory cytokines will result in increased production of the p47 phox component of the NADPH oxidase and ...subsequent production of reactive oxygen species (ROS). Methods Rat pancreatic islets or clonal rat BRIN BD11 beta cells were incubated in the presence of glucose, palmitic acid or pro-inflammatory cytokines for periods between 1 and 24 h. p47 phox production was determined by western blotting. ROS production was determined by spectrophotometric nitroblue tetrazolium or fluorescence-based hydroethidine assays. Results Incubation for 24 h in 0.1 mmol/l palmitic acid or a pro-inflammatory cytokine cocktail increased p47 phox protein production by 1.5-fold or by 1.75-fold, respectively, in the BRIN BD11 beta cell line. In the presence of 16.7 mmol/l glucose protein production of p47 phox was increased by 1.7-fold in isolated rat islets after 1 h, while in the presence of 0.1 mmol/l palmitic acid or 5 ng/ml IL-1β it was increased by 1.4-fold or 1.8-fold, respectively. However, palmitic acid or IL-1β-dependent production was reduced after 24 h. Islet ROS production was significantly increased after incubation in elevated glucose for 1 h and was completely abolished by addition of diphenylene iodonium, an inhibitor of NADPH oxidase or by the oligonucleotide anti-p47 phox . Addition of 0.1 mmol/l palmitic acid or 5 ng/ml IL-1β plus 5.6 mmol/l glucose also resulted in a significant increase in islet ROS production after 1 h, which was partially attenuated by diphenylene iodonium or the protein kinase C inhibitor GF109203X. However, ROS production was reduced after 24 h incubation. Conclusions/interpretation NADPH oxidase may play a key role in normal beta cell physiology, but under specific conditions may also contribute to beta cell demise.
Dental caries is a ubiquitous infectious disease with a nearly 100% lifetime prevalence. Rodent caries models are widely used to investigate the etiology, progression and potential prevention or ...treatment of the disease. To explore the suitability of these models for deeper investigations of intact surface zones during enamel caries, the structures of early‐stage carious lesions in rats were characterized and compared with previous reports on white spot enamel lesions in humans. Synchrotron X‐ray microcomputed tomography non‐destructively mapped demineralization in carious rat molar specimens across a range of caries severity, identifying 52 lesions across the 30 teeth imaged. Of these lesions, 13 were shown to have intact surface zones. Depth profiles of fractional mineral density were qualitatively similar to lesions in human teeth. However, the thickness of the surface zone in the rat model ranges from 10 to 58 µm, and is therefore significantly thinner than in human enamel. These results indicate that a fraction of lesions in rat caries possess an intact surface zone and are qualitatively similar to human lesions at the micrometer scale. This suggests that rat caries models may be a suitable analog through which to investigate the structure of surface zone enamel and its role during dental caries.
Synchrotron X‐ray microtomography non‐destructively maps demineralization within carious rat molar enamel. Depth profile analysis and lesion characterization reveals that many rat carious lesions possess intact surface zones that are similar in form but much thinner than those found in human caries.
We argue that the ratio S3=HΛ3/(He3×Λp) is a good representation of the local correlation between baryon number and strangeness, and therefore is a valuable tool to probe the nature of the dense ...matter created in high energy heavy-ion collisions: quark gluon plasma or hadron gas. A multiphase transport model (AMPT) plus a dynamical coalescence model is used to elucidate our arguments. We find that AMPT with string melting predicts an increase of S3 with increasing beam energy, and is consistent with experimental data, while AMPT with only hadronic scattering results in a low S3 throughout the energy range from AGS to RHIC, and fails to describe the experimental data.
Basic science, epidemiological and interventional research supports a link between vitamin D and tuberculosis (TB) immunity, infection and disease. We evaluated the association between vitamin D ...levels and TB infection and disease in UK children recruited to the National Institute for Health Research IGRA Kids Study (NIKS).
Children presenting between 2011 and 2014 were eligible if they had history of exposure to an adult case with sputum smear/culture-positive TB, or were referred and diagnosed with TB disease. Children were assessed at baseline and at 6-8 weeks for immunological evidence of TB infection (interferon-gamma release assay and/or tuberculin skin test) and evidence of TB disease. Some centres routinely measured total 25-hydroxy vitamin D (25-OHD) levels.
A total of 166 children were included. The median 25-OHD levels were higher in non-infected children (45.5 nmol/l) than in those with tuberculous infection (36.2 nmol/l) and TB disease (20.0 nmol/l). The difference between TB infection and disease was statistically significant (
< 0.001). By logistic regression, lower vitamin D levels were associated with TB disease among participants with infection or disease, with no evidence of confounding by age, sex, bacille Calmette-Guérin vaccination status, ethnicity, non-contact referral, season or centre.
Children with TB disease had lower vitamin D levels than children with infection. Implications for prevention and treatment remain to be established.
Background
The transobturator tape (TOT) has been utilized in the surgical management of SUI since 2001 when it was first described and is associated with minimal risk of trauma as its purely ...perineal insertion avoids entry to the retropubic space. Given its high success rate, low associated peri-operative morbidity and relative ease of insertion, it has been increasingly used as a day case procedure worldwide.
Aim
This study aims to demonstrate the suitability of the transobturator tape (TOT) as a day surgery procedure in the Republic of Ireland.
Methods
A retrospective review of all the patients who underwent TOT as a day case procedure at a tertiary referral centre in Dublin over a 1 year period (March 2015–March 2016) was carried out. This was post the introduction of the procedure as a day case for a select group of patients. The outcomes evaluated included intraoperative and postoperative complication rates, voiding dysfunction rates, unscheduled inpatient admissions following the procedure and continence rates post-procedure.
Results
Fifteen cases were reviewed. There was one case with minor intraoperative complication of bladder perforation which was managed as an outpatient. One patient (6 %) failed to achieve adequate voiding within the 6-h timeframe allowed and, therefore, required overnight admission. All patients reported dryness at the 6-week review. Major elective waiting time for the gynaecology list decreased from 28 to 10 weeks 1 year post-commencement of the protocol.
Conclusions
We conclude that the transobturator tape procedure is suitable as a day case in a select group of patients in the Irish healthcare setting. There was no increased rate of morbidity demonstrated in the group and readmission rates were low. It has reduced waiting times by increasing throughput of cases and ultimately will lead to reduced costs for hospitals.
Fragmented jurisdictions and decision making structures can result in destructive competition and/or a lack of systematic cooperation that can hamper effective resource management and environmental ...planning, although the value of local autonomy and stakeholder participations should not be underestimated. This study empirically examines if political fragmentation in local governance is a significant barrier to successful resource management. To test this hypothesis, the authors quantify the degree of political fragmentation at two different geographical scales – 1) site-level: 12-digit watersheds and 2) regional: metropolitan statistical areas or equivalent regions – and analyze how water resource management outcomes vary with the level of political fragmentation using nationwide land cover and stream gauge information in the U.S. Regression analysis shows water quality declines (or slower quality improvements), measured in terms of total suspended solids, are associated with both site-level and regional political fragmentation indicators, suggesting that political fragmentation can make resource management more challenging.
•The importance of governance structures in resource management is discussed.•Political fragmentation is quantified using various metrics.•The association between political fragmentation and water quality is analyzed.•Water quality changes are found to be associated with political fragmentation.
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