Waters recharging the subsurface contain a variety of naturally occurring geochemical components, the concentrations of which are principally a function of the atmosphere and surface environment. ...Over time, water-rock interactions and radiogenic processes in the subsurface control a complex geochemical evolution, impacting the initial surface-related signatures associated with recharged groundwaters. The rates of these geochemical changes are considerable in many important geologic settings, requiring characterisation and quantification of the dominant subsurface processes and evolving fluid characteristics. Constraining this is critically important for the discipline of fluid ‘age’ dating - hydrogeochronology. Age dating, or quantification of fluid residence times is typically evaluated through two categories of tracers; those that are incorporated at the point of recharge and decrease over time through radioactive decay (e.g. 3H, 14C, 81Kr) and those that increase over time (e.g. radiogenic noble gases) due to subsurface production and accumulation in fluids. As these fluids, elements, and tracers have different provenance, the calculated ‘age’ of any fluid represents the average, or mean residence time, of all components. Likewise, additional mechanisms of subsurface tracer production or loss can have significant bearing on any element-specific calculated residence times. The inevitable temporal discrepancies between tracers can be generated or accentuated in the subsurface which can prove difficult to reconcile in hydrogeochronologic modelling approaches.
By incorporating geochemical data into existing neutron flux-based models, this study evaluates specifically how subsurface production of ‘diminishing’ tracers in the fluid phase, via neutron capture of parent elements, can produce complexity in the dating of host fluids. The in situ rates and production routes of 3H, 14C, 36Cl 39Ar, and 81Kr in different subsurface fluids are modelled for a variety of host rock lithologies to evaluate the effect such baseline crustal production in different geochemical settings may have on calculated residence times within naturally occurring systems. In particular this model provides a quantitative evaluation for how site-specific subsurface radiogeochemistry may result in enhanced baselines of 36Cl, 39Ar, (and potentially 14C) relative to canonical assumptions, and substantially impact residence time estimates calculated from these tracers for a range of subsurface environments. Additionally, we evaluate the role geologic environments can have on low levels of baseline production and calculated residence times for 3H and 81Kr. This study quantitatively evaluates the dependence of geologic environments on these subsurface processes and the impacts this may have on hydrogeochronologic studies. The ability to quantify production of tracers in the subsurface and recalibrate associated residence times in a wide range of geologic settings is of direct relevance to areas such as groundwater resource management, Carbon Capture and Storage, hydrogen storage and nuclear waste management strategies, the hydrocarbon and energy industry, and investigations of the timing and evolution of subsurface microbial life.
Status and perspectives of neutrino physics Athar, M. Sajjad; Barwick, Steven W.; Brunner, Thomas ...
Progress in particle and nuclear physics,
20/May , Letnik:
124
Journal Article
Recenzirano
Odprti dostop
This review demonstrates the unique role of the neutrino by discussing in detail the physics of and with neutrinos. We deal with neutrino sources, neutrino oscillations, absolute masses, ...interactions, the possible existence of sterile neutrinos, and theoretical implications. In addition, synergies of neutrino physics with other research fields are found, and requirements to continue successful neutrino physics in the future, in terms of technological developments and adequate infrastructures, are stressed.
Most projects exist as part of a multi-project environment. The management of multiple projects presents challenges that are fundamentally different from single project management. Recent theoretical ...developments in the philosophy of complexity theory provide a basis for gaining insight into the proposition that multi-project management is neither an extension nor a scaled up version of single project management. Genuine multi-project environments exhibit the characteristics of complex adaptive systems which offer novel approaches for the project manager.
Serial biopsy of pancreatic ductal adenocarcinoma (PDAC), to chart tumour evolution presents a significant challenge. We examined the utility of circulating free DNA (cfDNA) as a minimally invasive ...approach across a cohort of 55 treatment-naïve patients with PDAC; 31 with metastatic and 24 with locally advanced disease. Somatic mutations in cfDNA were detected using next generation sequencing in 15/24 (62.5%) and 27/31 (87%) of patients with locally advanced and metastatic disease, respectively. Copy number changes were detected in cfDNA of 10 patients of whom 7 exhibited gain of chromosome 12p harbouring KRAS as well as a canonical KRAS codon 12 mutation. In multivariable Cox Regression analysis, we show for the first time that patients with KRAS copy number gain and KRAS mutation have significantly worse outcomes, suggesting that this may be linked to PDAC progression. The simple cfDNA assay we describe will enable determination of the presence of KRAS copy number gain and KRAS mutations in larger studies and clinical trials.
Marvell's experiences as traveling tutor, diplomat and political agent add a dimension of real international encounter in his poetry and prose that stands in addition to the literary citation or ...quotation of non-English books, and makes his verse distinctive among his contemporaries. This essay maps some of the literary landscape and the politics of literature in the places he visited in Europe, Russia and Scandinavia, and not least the monarchical absolutism experienced by some writers in these places. While some of this encounter and literary knowledge is reflected in his writing, other parts are not. The dominant pattern is that the north European encounter is in general not met by northern literary influence in Marvell's writing: features of citation, quotation, allusion and echo are largely to southern European sources: mostly French and Italian, but also Spanish. Marvell's interest in the longer history of lyric is set in the context of the Thirty Years War that seriously inhibited access to valuable ancient manuscripts. The question of the possible influence of some of Marvell's writings, especially his poetry, in seventeenth-century Europe is discussed. It is to be hoped that the geography of poetry begun here will help illuminate the European dimensions of Marvell's writings as more concrete details of his activities and his writings in Europe as well as in England are discovered. Keywords: diplomacy, patronage, politics, poetic form, Europe, poetic allusion
The osseous response to silicon (Si) level (0, 0.2, 0.4, 0.8 and 1.5
wt% Si) within 5 batches of matched porosity silicate-substituted hydroxyapatite (SA) scaffold was assessed by implantation of 4.6
...mm diameter cylinders in the femoral intercondylar notch of New Zealand White rabbits for periods of 1, 3, 6 and 12 weeks. Histological evaluation and histomorphometric quantification of bone ingrowth and mineral apposition rate (MAR) demonstrated the benefits to early (<1 week) bone ingrowth and repair through incorporation of Si, at all levels, in porous hydroxyapatite (HA) lattices as compared to stoichiometric (0
wt% Si) HA. The group containing 0.8
wt% Si supported significantly more bone ingrowth than all other groups at 3 and 6 weeks (
P
<
0.05
), initially through its elevated MAR between weeks 1 and 2, which was significantly higher than that of all other Si-containing groups (
P
<
0.05
). The level of silicate substitution also influenced the morphology and stability of the repair, with elevated levels of bone resorption and apposition apparent within other Si-containing groups at timepoints >3 weeks as compared to the 0 and 0.8
wt% Si groups. At 12 weeks, the net amount of bone ingrowth continued to rise in the 0, 0.8 and 1.5
wt% groups, apparently as a result of adaptive remodelling throughout the scaffold. Ingrowth levels remained highest in the 0.8
wt% Si group, was characterised by a dense trabecular morphology in the superficial region graduating to a more open network in the deep zone. These results highlight the sensitivity of healing response to Si level and suggest that an optimal response is obtained when SA is substituted with 0.8
wt% Si through its effect on the activity of both bone forming and bone resorbing cells.
SCLC accounts for approximately 250,000 deaths worldwide each year. Acquisition of adequate tumor biopsy samples is challenging, and liquid biopsies present an alternative option for patient ...stratification and response monitoring.
We applied whole genome next-generation sequencing to circulating free DNA (cfDNA) from 39 patients with limited-stage (LS) SCLC and 30 patients with extensive-stage SCLC to establish genome-wide copy number aberrations and also performed targeted mutation analysis of 110 SCLC associated genes. Quantitative metrics were calculated for copy number aberrations, including percent genome amplified (PGA the percentage of genomic regions amplified), Z-score (a measure of standard deviation), and Moran’s I (a measure of spatial autocorrelation). In addition CellSearch, an epitope-dependent enrichment platform, was used to enumerate circulating tumor cells (CTCs) from a parallel blood sample.
Genome-wide and targeted cfDNA sequencing data identified tumor-related changes in 94% of patients with LS SCLC and 100% of patients with extensive-stage SCLC. Parallel analysis of CTCs based on at least 1 CTC/7.5 mL of blood increased tumor detection frequencies to 95% for LS SCLC. Both CTC counts and cfDNA readouts correlated with disease stage and overall survival.
We demonstrate that a simple cfDNA genome-wide copy number approach provides an effective means of monitoring patients through treatment and show that targeted cfDNA sequencing identifies potential therapeutic targets in more than 50% of patients. We are now incorporating this approach into additional studies and trials of targeted therapies.
The increasing complexity and dynamics of construction projects have plagued the construction industry with substantial hazards and losses. Project risk management, therefore, has been recognised ...critical for the construction industry to improve their performance and secure the success of projects. Risk magnitude may be assessed by considering two parameters: risk likelihood and risk severity. However, there are many possible risk factors in construction, which lead to a project failure and these risk factors should be incorporated into the evaluation process. Factor index is therefore introduced to structure and evaluate these factors and integrate them into the decision making process of risk assessment. This article presents a risk assessment methodology to cope with risks in complicated construction situations. The application of fuzzy reasoning techniques provides an effective tool to handle the uncertainties and subjectivities arising in the construction process. A modified analytical hierarchy process is used to structure and prioritize diverse risk factors. Finally, an illustrative example on risk analysis of steel erection of the superstructure in a shopping centre is used to demonstrate the proposed methodology. The results indicate that by using the proposed methodology the risks associated with steel erection can be assessed effectively and efficiently.
This collection of essays studies the expression and diffusion of radical ideas in Britain from the period of the English Revolution in the mid-seventeenth century to the Romantic Revolution in the ...early nineteenth century. The essays included in the volume explore the modes of articulation and dissemination of radical ideas in the period by focusing on actors ('radical voices') and a variety of written texts and cultural practices ('radical ways'), ranging from fiction, correspondence, pamphlets and newspapers to petitions presented to Parliament and toasts raised in public. They analyse the way these media interacted with their political, religious, social and literary context. This volume provides an interdisciplinary outlook on the study of early modern radicalism,with contributions from literary scholars and historians, and uses case studies as insights into the global picture of radical ideas. It will be of interest to students of seventeenth- and eighteenth-century literature and history.
Large-scale manufacture of human embryonic stem cells (hESCs) is prerequisite to their widespread use in biomedical applications. However, current hESC culture strategies are labor-intensive and ...employ highly variable processes, presenting challenges for scaled production and commercial development. Here we demonstrate that passaging of the hESC lines, HUES7, and NOTT1, with trypsin in feeder-free conditions, is compatible with complete automation on the CompacT SelecT, a commercially available and industrially relevant robotic platform. Pluripotency was successfully retained, as evidenced by consistent proliferation during serial passage, expression of stem cell markers (OCT4, NANOG, TRA1-81, and SSEA-4), stable karyotype, and multi-germlayer differentiation in vitro, including to pharmacologically responsive cardiomyocytes. Automation of hESC culture will expedite cell-use in clinical, scientific, and industrial applications. Biotechnol. Bioeng. 2009;102: 1636-1644.
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