The effect of epoxy resins on the plasticity index of an A-6 soil

This thesis reports the results of an investigation of the variation in plasticity of a clayey soil after treatment with small quantities of epoxy resin and curing agent or with curing agent alone. The series of samples tested consisted of an A-6 soil obtained from the vicinity of Rolla, Missouri, combined with: 1. 0-3% of triethylenetetramine hereafter referred to as TETA. 2. 0-3% of diethylenetriamine hereafter referred to as DETA. 3. 0-3% of Araldite 6010 resin cured with TETA. The TETA content was varied form 20% to 100% of the resin by weight. 4. 0-3% Araldite 6010 resin cured with DETA. The DETA content was varied from 20% to 100% of the resin by weight. The plasticity index of the treated soil samples was computed by conventional soil testing procedures. The relative amount of unreacted amine remaining in samples was determined by titration. Qualitative relationships were found between the plasticity index and the type and quantity of additive used. The complexities of these relationships are discussed and suggestions for further research are made --Abstract, page ii

The relationship between local scalp skin temperature and cutaneous perfusion during scalp cooling

Cooling the scalp during administration of chemotherapy can prevent hair loss. It reduces both skin blood flow and hair follicle temperature, thus affecting drug supply and drug effect in the hair follicle. The extent to which these mechanisms contribute to the hair preservative effect of scalp cooling remains unknown. The purpose of this study was to establish a relationship between local scalp skin temperature and cutaneous blood flow during scalp cooling. We measured skin temperature and cutaneous perfusion during a cooling and re-warming experiment. Experiments on a single subject showed that the measurements were reproducible and that the response was identical for the two positions that were measured. Inter-subject variability was investigated on nine subjects. We found that for the first 10 °C of cooling, perfusion of the scalp skin decreases to below 40%. Perfusion can be further reduced to below 30% by a few degrees more cooling, but a plateau is reached after that. We found that a generally accepted relation in thermal physiology between temperature and perfusion (i.e. Q10 relation) does not describe the data well, but we found an alternative relation that describes the average behavior significantly better

Evaluation of a multimode fiber optic low coherence interferometer for path length resolved Doppler measurements of diffuse light \ud

The performance of a graded index multimode fiber optic low coherence Mach-Zehnder interferometer with phase modulation is analyzed. Investigated aspects were its ability to measure path length distributions and to perform path length resolved Doppler measurements of multiple scattered photons in a turbid suspension of particles undergoing Brownian and translational motion. The path length resolution of this instrument is compared with a system using single mode fibers for illumination and detection. The optical path lengths are determined from the zero order moment of the phase modulation peak in the power spectrum. The weighted first moment, which is equal to the average Doppler shift, shows a linear response for different mean flow velocities within the physiological rang

Managed groundwater development for water-supply security in Sub-Saharan Africa: Investment priorities

In numerous countries of Sub-Saharan Africa the strategic agenda of the water-sector is undergoing substantial change because of demographic pressure, climate change and economic transformation. Two new policy questions are arising from the need to make better use of available groundwater storage to improve water-supply security:• What is the scope for promoting much increased groundwater use for irrigated agriculture, and how might the investment risks be reduced and sustainable outcomes ensured?• How can the demand to expand urban groundwater use, for both further supplementing municipal water-supply systems and for direct in situ water supply, be best channelled to maximise the benefits whilst minimising the risks?This ‘new agenda’ poses very different challenges from the long-standing requirement to provide rural water supplies of adequate coverage, reliability and quality (which, while still not yet fully addressed, is outside the scope of this paper). Balanced answers to these new questions are needed to provide a sound basis for appropriate investment policies on managed groundwater development and adequate institutional provisions for their implementation. They are discussed here from the standpoint of the GW-MATE experience in some World Bank-supported projects in eastern Africa during 2001-2010, together with a review of some developments in western Africa and insights from parts of Asia and Latin America

The crude protein production of grassland and the utilization by milking cows.

An attempt was made with experimental data of various origins to quantify the intake of N from pasture grass by milking cows during the grazing period. It was also demonstrated how much of this N was removed by secretion in the milk as well as the conc. of N in the faeces and in the urine remaining on the pasture after grazing. From a fertilizer application to the pasture of 450 kg N/ha yr an equal conc. was taken up by the herbage. Of this herbage N about 75-80% remained on the pasture after grazing. The conc. remaining on the grassland increased sharply with increasing N rates and this went parallel with an increasing intensity in the N circulation in the system soil-plant-animal-soil and a rising NO3 content in the surface layer of ground water. (Abstract retrieved from CAB Abstracts by CABI’s permission

A Framework for Directional and Higher-Order Reconstruction in Photoacoustic Tomography

Photoacoustic tomography is a hybrid imaging technique that combines high optical tissue contrast with high ultrasound resolution. Direct reconstruction methods such as filtered backprojection, time reversal and least squares suffer from curved line artefacts and blurring, especially in case of limited angles or strong noise. In recent years, there has been great interest in regularised iterative methods. These methods employ prior knowledge on the image to provide higher quality reconstructions. However, easy comparisons between regularisers and their properties are limited, since many tomography implementations heavily rely on the specific regulariser chosen. To overcome this bottleneck, we present a modular reconstruction framework for photoacoustic tomography. It enables easy comparisons between regularisers with different properties, e.g. nonlinear, higher-order or directional. We solve the underlying minimisation problem with an efficient first-order primal-dual algorithm. Convergence rates are optimised by choosing an operator dependent preconditioning strategy. Our reconstruction methods are tested on challenging 2D synthetic and experimental data sets. They outperform direct reconstruction approaches for strong noise levels and limited angle measurements, offering immediate benefits in terms of acquisition time and quality. This work provides a basic platform for the investigation of future advanced regularisation methods in photoacoustic tomography.Comment: submitted to "Physics in Medicine and Biology". Changes from v1 to v2: regularisation with directional wavelet has been added; new experimental tests have been include

Genome-wide methylome analysis using MethylCap-seq uncovers 4 hypermethylated markers with high sensitivity for both adeno- and squamous-cell cervical carcinoma

Background: Cytology-based screening methods for cervical adenocarcinoma (ADC) and to a lesser extent squamous-cell carcinoma (SCC) suffer from low sensitivity. DNA hypermethylation analysis in cervical scrapings may improve detection of SCC, but few methylation markers have been described for ADC. We aimed to identify novel methylation markers for the early detection of both ADC and SCC. Results: Genome-wide methylation profiling for 20 normal cervices, 6 ADC and 6 SCC using MethylCap-seq yielded 53 candidate regions hypermethylated in both ADC and SCC. Verification and independent validation of the 15 most significant regions revealed 5 markers with differential methylation between 17 normals and 13 cancers. Quantitative methylation-specific PCR on cervical cancer scrapings resulted in detection rates ranging between 80% and 92% while between 94% and 99% of control scrapings tested negative. Four markers (SLC6A5, SOX1, SOX14 and TBX20) detected ADC and SCC with similar sensitivity. In scrapings from women referred with an abnormal smear (n = 229), CIN3+ sensitivity was between 36% and 71%, while between 71% and 93% of adenocarcinoma in situ (AdCIS) were detected; and CIN0/1 specificity was between 88% and 98%. Compared to hrHPV, the combination SOX1/SOX14 showed a similar CIN3+ sensitivity (80% vs. 75%, respectively, P>0.2), while specificity improved (42% vs. 84%, respectively, P < 10(-5)). Conclusion: SOX1 and SOX14 are methylation biomarkers applicable for screening of all cervical cancer types

A randomized controlled trial to test the effect of multispecies probiotics on cognitive reactivity to sad mood

AbstractBackground: Recent insights into the role of the human microbiota in cognitive and affective functioning have led to the hypothesis that probiotic supplementation may act as an adjuvant strategy to ameliorate or prevent depression. Objective: Heightened cognitive reactivity to normal, transient changes in sad mood is an established marker of vulnerability to depression and is considered an important target for interventions. The present study aimed to test if a multispecies probiotic containing Bifidobacterium bifidum W23, Bifidobacterium lactis W52, Lactobacillus acidophilus W37, Lactobacillus brevis W63, Lactobacillus casei W56, Lactobacillus salivarius W24, and Lactococcus lactis (W19 and W58) may reduce cognitive reactivity in non-depressed individuals. Design: In a triple-blind, placebo-controlled, randomized, pre- and post-intervention assessment design, 20 healthy participants without current mood disorder received a 4-week probiotic food-supplement intervention with the multispecies probiotics, while 20 control participants received an inert placebo for the same period. In the pre- and post-intervention assessment, cognitive reactivity to sad mood was assessed using the revised Leiden index of depression sensitivity scale. Results: Compared to participants who received the placebo intervention, participants who received the 4-week multispecies probiotics intervention showed a significantly reduced overall cognitive reactivity to sad mood, which was largely accounted for by reduced rumination and aggressive thoughts. Conclusion: These results provide the first evidence that the intake of probiotics may help reduce negative thoughts associated with sad mood. Probiotics supplementation warrants further research as a potential preventive strategy for depression