Integrated waveguide and nanostructured sensor platform for surface-enhanced Raman spectroscopy

Limitations of current sensors include large dimensions, sometimes limited sensitivity and inherent single-parameter measurement capability. Surface-enhanced Raman spectroscopy can be utilized for environment and pharmaceutical applications with the intensity of the Raman scattering enhanced by a factor of 106. By fabricating and characterizing an integrated optical waveguide beneath a nanostructured precious metal coated surface a new surface-enhanced Raman spectroscopy sensing arrangement can be achieved. Nanostructured sensors can provide both multiparameter and high-resolution sensing. Using the slab waveguide core to interrogate the nanostructures at the base allows for the emission to reach discrete sensing areas effectively and should provide ideal parameters for maximum Raman interactions. Thin slab waveguide films of silicon oxynitride were etched and gold coated to create localized nanostructured sensing areas of various pitch, diameter, and shape. These were interrogated using a Ti:Sapphire laser tuned to 785-nm end coupled into the slab waveguide. The nanostructured sensors vertically projected a Raman signal, which was used to actively detect a thin layer of benzyl mercaptan attached to the sensors

Local temperature-sensitive mechanisms are important mediators of limb tissue hyperemia in the heat-stressed human at rest and during small muscle mass exercise.

Limb tissue and systemic blood flow increases with heat stress, but the underlying mechanisms remain poorly understood. Here, we tested the hypothesis that heat stress-induced increases in limb tissue perfusion are primarily mediated by local temperature-sensitive mechanisms. Leg and systemic temperatures and hemodynamics were measured at rest and during incremental single-legged knee extensor exercise in 15 males exposed to 1 h of either systemic passive heat-stress with simultaneous cooling of a single leg (n=8) or isolated leg heating or cooling (n=7). Systemic heat-stress increased core, skin and heated leg blood (Tb) temperatures, cardiac output and heated leg blood flow (LBF, 0.6 ± 0.1 l.min(-1); P0.05). Increased heated leg deep tissue BF was closely related to Tb (R(2) = 0.50; P0.05), despite unchanged systemic temperatures and hemodynamics. During incremental exercise, heated LBF was consistently maintained ~ 0.6 l.min(-1) higher than that in the cooled leg (P<0.01), with LBF and vascular conductance in both legs showing a strong correlation with their respective local Tb (R(2) = 0.85 and 0.95, P<0.05). We conclude that local temperature-sensitive mechanisms are important mediators in limb tissue perfusion regulation both at rest and during small-muscle mass exercise in hyperthermic humans.The invasive study was partially funded by Gatorade Sports Science Institute, PepsiCo

Socioeconomic indicators of health inequalities and female mortality: a nested cohort study within the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS)

Evidence is mounting that area-level socioeconomic indicators are important tools for predicting health outcomes. However, few studies have examined these alongside individual-level education. This nested cohort study within the control arm of the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) assesses the association of mutually adjusted individual (education) and area-level (Index of Multiple Deprivation-IMD 2007) socioeconomic status indicators and all-cause female mortality

A multivariable hospital-based retrospective analysis of factors affecting non-surgical periodontal treatment response in the East London population

Periodontitis is a chronic inflammatory disease, initiated by dental plaque bacteria and characterised by destruction of the tooth supporting tissues including alveolar bone. Historically, disease progression in periodontitis was thought to be correlated with the amount of plaque biofilm (Frunker and Gardner, 1956, Grant D et al., 1968, Russell, 1964, Waerhaug, 1956). However, our current understanding of the disease suggests that a loss in equilibrium between the commensal and pathogenic microorganisms (dysbiosis) and the reduction of the protective host response drives the disease. Since periodontitis is initiated by bacterial subgingival biofilms, mechanical removal of subgingival products and plaque retentive factors (e.g., calculus) is required. Although, complete removal of deposits is frequently not achieved (Waerhaug, 1978, Eaton et al., 1985, Caffesse et al., 1986, Sherman et al., 1990, Wylam et al., 1993, Breininger et al., 1987, Rateitschak-Pluss et al., 1992), mechanical non-surgical periodontal treatment (NSPT) continues to be an integral part of periodontal therapy. NSPT comprising of root surface debridement (RSD) alongside adequate oral hygiene to reduce bacterial load, not only improves gingival health and arrests disease progression (Heitz-Mayfield, 2005, Suvan, 2005, Cobb, 1996, Van der Weijden and Timmerman, 2002), but also reduces the risk of tooth loss (Badersten et al., 1985b, Badersten et al., 1985a, Badersten et al., 1984). The efficacy and effectiveness of NSPT is proven by many studies demonstrating reductions in periodontal probing depths (PPD), clinical attachment level (CAL) gain and bleeding on probing (BOP) (Van der Weijden and Timmerman, 2002, Trombelli et al., 2015, Suvan, 2005, Badersten et al., 1984, Suvan et al., 2020). Clinical outcomes of NSPT can be influenced by several factors including age (Trombelli et al., 2010), gender (Mascarenhas et al., 2003), cigarette smoking (Papantonopoulos, 1999, Pahkla et al., 2006, Wan et al., 2009), diabetes (Christgau et al., 1998, Tervonen and Karjalainen, 1997), operator experience (Fleischer et al., 1989) and patient compliance (Leininger et al., 2010). The Royal London Dental Hospital (RLH) in Tower Hamlets is one of the most socio-economically deprived and ethnically diverse boroughs in the UK. Recent data from a large sample of our local East London population has suggested that periodontitis is more severe in minority ethnic groups (Delgado-Angulo et al., 2016). Although, in general these groups are frequently under-represented in clinical outcome studies compared to Caucasian populations (Jiao et al., 2017). Therefore, there is a need to better understand the factors influencing non-surgical success in our local East London population. The aim of this hospital-based retrospective study was therefore to evaluate factors influencing the effectiveness of NSPT in patients referred for periodontal treatment at Royal London Dental Hospital using data extracted from their clinical records. We also wanted to specifically assess if individuals from a South East Asian (SEA) ethnic background had poorer outcomes after NSPT. Univariate, bivariate, and multivariate analysis to measure the relative contributions of the different factors in the local population of East London. Mean PPD change was the primary outcome variable. In this study, from a sample size of 108 patients, no differences were found between ethnicities or between the SEA group and ‘others’ group in relation to NSPT outcome measured by mean PPD change. There were however differences between the SEA and other groups in terms of age of referral, levels of self-reported attendance, and levels of stress. Plaque scores at reassessment did not impact NSPT outcome but compliant patient had poorer outcomes. However univariate analysis showed that patients achieving at least a 10% improvement in plaque between baseline and reassessment showed better non-surgical treatment outcomes. There were also significant differences in NSPT response when comparing patients reassessed at 120 days (n=28). Baseline Disease severity was the only significant predictor of good treatment response in the binary logistic regression model which explained 26.6% of the variability in the dependent outcome variable. The multilevel analysis also showed that patients presenting with higher levels of disease (Highest 50% percentile) at baseline (Mean PPD) are 3.9 times more likely to have a good non-surgical treatment response (more pocket depth reduction) compared to those with lower levels of disease (Lowest 50% percentile). However all other variables were non-significant in this model, whilst many factors significant in the univariate analysis became non-significant when combined into the same binary logistic regression model. There are several limitations to this study especially in terms of the number of patients we were able to recruit which may explain some of the outcomes which contradict previous studies

Fuel economy analysis of part-load variable camshaft timing strategies in two modern small-capacity spark ignition engines

Variable Camshaft Timing strategies have been investigated at part-load operating conditions in two 3-cylinder, 1.0-litre, Spark Ignition engines. The two small-size engines are different variants of the same 4-valve/cylinder, pent-roof design platform. The first engine is naturally aspirated, port fuel injection and features high nominal compression ratio of 12:1. The second one is the turbo-charged, direct injection version, featuring lower compression ratio of 10:1. The aim of the investigation has been to identify optimal camshaft timing strategies which maximise engine thermal efficiency through improvements in brake specific fuel consumption at fixed engine load. The results of the investigation show that the two engines demonstrate consistent thermal efficiency response to valve timing changes in the low and mid part-load envelope, up to a load of 4 bar BMEP. At the lower engine loads investigated, reduced intake valve opening advance limits the hot burned gas internal recirculation, while increasingly retarded exhaust valve opening timing favours engine efficiency through greater effective expansion ratio. At mid load (4 bar BMEP), a degree of intake advance becomes beneficial, owing mostly to the associated intake de-throttling. In the upper part-load domain, for engine load of 5 bar BMEP and above, the differences between the two engines determine very different efficiency response to the valve timing setting. The lower compression ratio engine continues to benefit from advanced intake valve timing, with a moderate degree of exhaust timing retard, which minimises the exhaust blow-down losses. The higher compression ratio engine is knock-limited, forcing the valve timing strategy towards regions of lower intake advance and lower hot gas recirculation. The theoretical best valve timing strategy determined peak fuel economy improvements in excess of 8% for the port fuel injection engine; the peak improvement was 5% for the more efficient direct injection engine platform

Thermal Analysis of Copper Salicylate Tetrahydrate

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Metformin reduces airway glucose permeability and hyperglycaemia-induced Staphylococcus aureus load independently of effects on blood glucose

Background Diabetes is a risk factor for respiratory infection, and hyperglycaemia is associated with increased glucose in airway surface liquid and risk of Staphylococcus aureus infection. Objectives To investigate whether elevation of basolateral/blood glucose concentration promotes airway Staphylococcus aureus growth and whether pretreatment with the antidiabetic drug metformin affects this relationship. Methods Human airway epithelial cells grown at air–liquid interface (±18 h pre-treatment, 30 μM–1 mM metformin) were inoculated with 5×105 colony-forming units (CFU)/cm2 S aureus 8325-4 or JE2 or Pseudomonas aeruginosa PA01 on the apical surface and incubated for 7 h. Wild-type C57BL/6 or db/db (leptin receptor-deficient) mice, 6–10 weeks old, were treated with intraperitoneal phosphate-buffered saline or 40 mg/kg metformin for 2 days before intranasal inoculation with 1×107 CFU S aureus. Mice were culled 24 h after infection and bronchoalveolar lavage fluid collected. Results Apical S aureus growth increased with basolateral glucose concentration in an in vitro airway epithelia–bacteria co-culture model. S aureus reduced transepithelial electrical resistance (RT) and increased paracellular glucose flux. Metformin inhibited the glucose-induced growth of S aureus, increased RT and decreased glucose flux. Diabetic (db/db) mice infected with S aureus exhibited a higher bacterial load in their airways than control mice after 2 days and metformin treatment reversed this effect. Metformin did not decrease blood glucose but reduced paracellular flux across ex vivo murine tracheas. Conclusions Hyperglycaemia promotes respiratory S aureus infection, and metformin modifies glucose flux across the airway epithelium to limit hyperglycaemia-induced bacterial growth. Metformin might, therefore, be of additional benefit in the prevention and treatment of respiratory infection

Circulation characteristics of a monsoon depression during BOBMEX-99 using high-resolution analysis

The skill and efficiency of a numerical model mostly varies with the quality of initial values, accuracy on parameterization of physical processes and horizontal and vertical resolution of the model. Commonly used low-resolution reanalyses are hardly able to capture the prominent features associated with organized convective processes in a monsoon depression. The objective is to prepare improved high-resolution analysis by the use of MM5 modelling system developed by the Pennsylvania State University/National Center for Atmospheric Research (PSU/NCAR). It requires the objective comparison of high and low-resolution analysis datasets in assessing the specific convective features of a monsoon depression. For this purpose, reanalysis datasets of NCAR/NCEP (National Center for Atmospheric Research/National Centers for Environmental Prediction) at a horizontal resolution of 2.5° (latitude/longitude) have been used as first guess in the objective analysis scheme. The additional asynoptic datasets obtained during BOBMEX-99 are utilized within the assimilation process. Cloud Motion Wind (CMW) data of METEOSAT satellite and SSM/I surface wind data are included for the improvement of derived analysis. The multiquadric (MQD) interpolation technique is selected and applied for meteorological objective analysis at a horizontal resolution of 30 km. After a successful inclusion of additional data, the resulting reanalysis is able to produce the structure of convective organization as well as prominent synoptic features associated with monsoon depression. Comparison and error verifications have been done with the help of available upper-air station data. The objective verification reveals the efficiency of the analysis scheme

Lignin peroxidases, manganese peroxidases, and other ligninolytic enzymes produced by Phlebia radiata during solid-state fermentation of wheat-straw

The white rot fungus Phlebia radiata 79 (ATCC 64658) produces lignin peroxidase (LiP), manganese peroxidase (MnP), glyoxal oxidase (GLOX), and laccase in the commonly used glucose low-nitrogen liquid medium. However, the enzymes which this fungus utilizes for selective removal of lignin during degradation of different lignocellulosic substrates have not been studied before. Multiple forms of LiP, MnP, GLOX, and laccase were purified from P. radiata culture extracts obtained after solid-state fermentation of wheat straw. However, the patterns of extracellular lignin-modifying enzymes studied were different from those of the enzymes usually found in liquid cultures of P. radiata. Three LiP isoforms were purified. The major LiP isoform from solid-state cultivation was LiP2. LiP3, which has usually been described as the major isoenzyme in liquid cultures, was not expressed during straw fermentation. New MnP isoforms have been detected in addition to the previously reported MnPs. GLOX was secreted in rather high amounts simultaneously with LiP during the first 2 weeks of growth. GLOX purified from P. radiata showed multiple forms, with pIs ranging from 4.0 to 4.6 and with a molecular mass of ca. 68 kDa

Histological effects of fibrin glue and synthetic tissue glues on the spinal cord: are they safe to use?

INTRODUCTION: Fibrin glues such as Tisseel(®) have been established in neurosurgery for over thirty years. They are recommended for extradural use but have intradural applications. Brachial plexus reimplantation after trauma requires intradural fibrin glue because reimplanted nerves cannot be sutured to the spinal cord. Recently synthetic glues have become popular in spinal surgery but there is limited information about their safety. Our study compared the histological effects of Tisseel(®), Adherus(®) and BioGlue(®) on spinal cord using our rat brachial plexus repair model. MATERIALS & METHODS: Randomised observational animal study. Forty-one Sprague-Dawley rats divided in to control (n = 9), Tisseel(®) (n = 8), BioGlue(®) (n = 10) and Adherus(®) (n = 14) groups. Under general anaesthesia a posterior midline cervical incision was made and hemi-laminectomies performed at C7 and T1. Dura was opened and T1 dorsal root transected and repositioned on the spinal cord. Two drops of Tisseel(®), BioGlue(®), Adherus(®) or no glue (control) were applied over the cut nerve and cord. At days 7, 14 and 28 rats were euthanized, processed and sections stained with Haematoxylin & Eosin and evaluated blind by a neuropathologist. RESULTS: Control and Tisseel(®) groups showed only mild focal inflammation in the cord. Adherus(®) and Bioglue(®) groups showed evidence of spinal cord inflammation and degeneration. All BioGlue(®) and Adherus(®) rats had evidence of distortion of the cord from the glue mass at all time points. Two BioGlue(®)-treated and one Adherus(®)-treated rat developed a hemiparesis. One BioGlue(®) rat developed hind limb paralysis. One BioGlue(®) rat failed to wake up at the end of the procedure. There were no complications in control and Tisseel(®) groups. CONCLUSION: Tisseel(®) caused a similar inflammatory response to control and may be used on spinal cord. BioGlue(®) and Adherus(®) should be applied thinly for a watertight dural closure but intradural use and contact with spinal tissue must be avoided