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Abstract: Kilometre‐scale geobodies of diagenetic origin have been documented for the first time in a high‐resolution 3D seismic survey of the Upper Cretaceous chalks of the Danish Central Graben, North Sea Basin. Based on detailed geochemical, petrographic and petrophysical analyses, it is demonstrated that the geobodies are of an open‐system diagenetic origin caused by ascending basin fluids guided by faults and stratigraphic heterogeneities. Increased amounts of porosity‐occluding cementation, contact cement and/or high‐density/high‐velocity minerals caused an impedance contrast that can be mapped in seismic data, and represent a hitherto unrecognized, third type of heterogeneity in the chalk deposits in addition to the well‐known sedimentological and structural features. The distribution of the diagenetic geobodies is controlled by porosity/permeability contrasts of stratigraphic origin, such as hardgrounds associated with formation tops, and the feeder fault systems. One of these, the Top Campanian Unconformity at the top of the Gorm Formation, is particularly effective and created a basin‐wide barrier separating low‐porosity chalk below from high‐porosity chalk above (a Regional Porosity Marker, RPM). It is in particular in this upper high‐porosity unit (Tor and Ekofisk Formations) that the diagenetic geobodies occur, delineated by “Stratigraphy Cross‐cutting Reflectors” (SCRs) of which eight different types have been distinguished. The geobodies have been interpreted as the result of: (i) escaping pore fluids due to top seal failure, followed by local mechanical compaction of high‐porous chalks, paired with (ii) ascension of basinal diagenetic fluids along fault systems that locally triggered cementation of calcite and dolomite within the chalk, causing increased contact cements and/or reducing porosity. The migration pathway of the fluids is marked by the SCRs, which are the outlines of high‐density bodies of chalk nested in highly porous chalks. This study, thus, provides new insights into the 3D relationship between fault systems, fluid migration and diagenesis in chalks and has important applications for basin modelling and reservoir characterization. [ABSTRACT FROM AUTHOR]

The crystal structure of cesbronite has been determined using single‐crystal X‐ray diffraction and supported by electron‐microprobe analysis, powder diffraction and Raman spectroscopy. Cesbronite is orthorhombic, space group Cmcm, with a = 2.93172 (16), b = 11.8414 (6), c = 8.6047 (4) Å and V = 298.72 (3) Å3. The chemical formula of cesbronite has been revised to CuII3TeVIO4(OH)4 from CuII5(TeIVO3)2(OH)6·2H2O. This change has been accepted by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association, Proposal 17‐C. The previously reported oxidation state of tellurium has been shown to be incorrect; the crystal structure, bond valence studies and charge balance clearly show tellurium to be hexavalent. The crystal structure of cesbronite is formed from corrugated sheets of edge‐sharing CuO6 and (Cu0.5Te0.5)O6 octahedra. The structure determined here is an average structure that has underlying ordering of Cu and Te at one of the two metal sites, designated as M, which has an occupancy Cu0.5Te0.5. This averaging probably arises from an absence of correlation between adjacent polyhedral sheets, as there are two different hydrogen‐bonding configurations linking sheets that are related by a ½a offset. Randomised stacking of these two configurations results in the superposition of Cu and Te and leads to the Cu0.5Te0.5 occupancy of the M site in the average structure. Bond‐valence analysis is used to choose the most probable Cu/Te ordering scheme and also to identify protonation sites (OH). The chosen ordering scheme and its associated OH sites are shown to be consistent with the revised chemical formula. [ABSTRACT FROM AUTHOR]

The high-pressure silicate K1.5Mg2Si2O7H0.5, synthesized and characterized by Welch et al. [(2012), Am. Mineral. 97, 1849-1857], has been re-examined with the aim of determining the nature of the superstructure noted in their study. The composition corresponds to a 1:1 combination of KMg2Si2O7H and end-members, but it is not a solid solution. Single-crystal X-ray diffraction data for one of the original K1.5Mg2Si2O7H0.5 crystals synthesized at 16 GPa/1573 K, has been collected using a much longer exposure time in order to improve the intensity statistics of weak superlattice reflections identified by Welch et al. (2012). The superstructure has been determined using a superspace approach as having the superspace group Cmcm(0,β,0)00s and t0 = 1/16 with refined parameters a = 8.7623 (10), b = 5.0703 (7), c = 13.2505 (11) Å , V = 588.69 (12) Å 3. This structure corresponds to one with the conventional space group Pbnm and unit-cell parameters a = 8.7623 (10), b = 20.281 (3), c = 13.2505 (11) Å , V= 2354.7 (5) Å 3 and is based upon a super-sheet motif in which ordering involves rows of pairs of vacant interlayer K sites. This is the third topologically distinct structure type for the KMg2Si2O7H-K2Mg2Si2O7 join and suggests that there is very limited solid solution, and so it can be expected that each of the three structures (P63cm, P31m and Pbnm) has its own stability field, rather than being part of a continuous compositional series based upon a single structure type. As such, K1.5Mg2Si2O7H0.5 should be considered as a potentially significant host of K in the Earth's mantle. [ABSTRACT FROM AUTHOR]

ABSTRACT Recently, there has been significant research in the area of organic electrochemical transistors (OECTs) because of their superior aptitude of chemical and biological sensing. Here it is shown for the first time the incorporation of polymer brushes to a transistor. Polymer brushes were chosen for their biocompatible properties and their ability to covalently tether enzymes and other biomolecules to different surfaces. OECTs were fabricated from the conducting polymer poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate), PEDOT:PSS, and polymerized from the surface a mixed polymer brush of poly(glycidyl methacrylate) and poly(2-hydroxyethyl methacrylate). The brushes were functionalized with glucose oxidase and measured in terms of electrical performance and long-term stability. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 372-377 [ABSTRACT FROM AUTHOR]

ABSTRACT While polymer brush systems continue to grow in popularity, so does their complexity and sophistication. Advances in polymerization and specific functionalization methods have led to novel applications in diverse research fields. The marriage of top-down lithography with bottom-up brush processing is becoming increasingly important in the development and progress of nanotechnology. The aim of this review is to examine different approaches taken to generate tailored polymer brush systems through surface-initiated polymerizations as well as patterning techniques. Detaching polymer brushes to create free-standing membranes is also highlighted and discussed in terms of methods and characterization. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1457-1472 [ABSTRACT FROM AUTHOR]

Aliment Pharmacol Ther 2012; 35: 126-132 Summary Background The prevalence of diabetes is increasing rapidly. Given its pro-inflammatory nature, comorbid diabetes may affect the course of Crohn's disease (CD). Aim To determine whether comorbid diabetes influences the natural history of CD. Methods We compared a cohort with CD and comorbid diabetes to a nondiabetic control population and calculated the period prevalence of surgical intervention over a 5-year period. Unadjusted and adjusted odds-ratios were calculated regarding the need for surgical intervention using univariate and multivariate logistic regression. Results A total of 240 patients were identified, 16 of whom were diabetics (6.7%). The period prevalence of CD-specific surgery in the diabetic cases was 75.0% and in the nondiabetic controls, 31.7%. The diabetic patients were more obese than the controls (44% vs. 10%; P < 0.0001) and older than the controls (47.4 years vs. 38.6; P < 0.01). There was no difference in the frequency of biologic therapy use, immunomodulator use, smoking, perianal disease, ileal involvement or corticosteroid use between the diabetics and controls. Univariate analysis revealed that diabetes (OR 6.46 [95% CI 2.01-20.8]), smoking (OR 2.46 [95% CI 1.24-4.90]), ileal disease (OR 2.21 [95% CI 1.15-4.24]) and obesity (OR 2.22 [95% CI 1.04-4.77]) were risk factors for needing surgery. After adjustment for covariates, the OR for surgical intervention in diabetics was 5.4 (95% CI 1.65-17.64). Conclusion Co-morbid diabetes in patients with Crohn's disease predicts a greater need for surgical intervention. [ABSTRACT FROM AUTHOR]

Drama, like nursing, concerns itself with the human condition and finds its resonance in an empathetic response to the person-to-person connection. As part of their clinical experience in the mental health component of their undergraduate nursing course, 80 student nurses attended the play Bearing Witness written by the authors and produced as a joint Faculty production between the Faculty of Nursing and the Department of Drama at the University of Alberta, Edmonton, Canada. The play charts and interweaves the paths to healing of two people following incestuous abuse for one, and political torture for the other, and poses questions to the audience concerning the intent and effects of abuse, and the place and value of forgiveness and forgiving. Some 4-5 months afterwards the students were invited to participate in hour-long, semi-structured interviews to investigate the persistent impressions of the play, the students' perceptions of the themes and relevance and the effect of the play on their learning and development as nurses. The seven students who took part in the interviews expressed that their feelings of empathy and identification with the situation of the characters in the play had a greater impact on their learning than other methods of instruction they had evaluated, particularly in terms of the persistence and processing of the subjective experience. Other notable themes were that of forgiveness, its value in healing and the implications for nursing, and an appreciation of the 'spiritual component' of the total learning experience. [ABSTRACT FROM AUTHOR]

Background Cyclooxygenase (COX)-2 is an inducible enzyme responsible for catalysing the formation of prostaglandins (PGs) in settings of inflammation. Single nucleotide polymorphisms (SNPs) of the COX-2 gene may influence gene transcription and PG production in the asthmatic airway. Objective To evaluate the frequencies of COX-2 SNPs in an Australian Caucasian population, and determine potential associations between common COX-2 promoter SNPs and asthma, asthma severity and aspirin-intolerant asthma (AIA). Methods The frequencies of 25 COX-2 SNPs were determined in a random population ( n=176). The SNPs with a minor allele frequency of >10% were then studied in asthmatic ( n=663), non-asthmatic controls ( n=513) and AIA subjects ( n=58). Genotype, allele and haplotype associations were assessed. Functional assessment of SNPs was performed by transfection into HeLa cells measured using the luciferase dual-reporter assay system. Results Eighteen COX-2 SNPs were not detected, five were rare and two promoter SNPs, −1195G>A (rs689465), and −1290A>G (rs689466), were further studied. The A allele of the −1195 SNP was present at a significantly higher frequency among all asthmatic subjects ( P=0.012). Over 60% of the asthmatic individuals were −1195A homozygotes compared with 54.6% of the control subjects (odds ratio, 1.35; 95% CI, 1.06–1.72, P=0.03). After classifying for severity, the mild asthmatics represented 64.6% of −1195AA individuals, the highest of all the asthma groups compared with 54.6% of the control subjects (odds ratio, 1.5; 95% CI, 1.12–2.02, P=0.02). The −1290A/−1195G/−765G haplotype was associated with a reduced incidence of asthma (odds ratio, 0.76; 95% CI, 0.61–0.95, P=0.017). Conclusion The −1195G>A polymorphism appears to be associated with asthma, and in particular with mild asthma. [ABSTRACT FROM AUTHOR]

It is perhaps conventional wisdom that the therapeutic relationship is a cornerstone of psychiatric nursing. It is almost a sine qua non. However, while its importance may be widely recognized, it is notoriously undefined and even those who profess to practise or utilize it, or those who advocate it most strongly, have difficulty in saying exactly what it is. This report details a study carried out with six experienced psychiatric nurses to explore and describe perceptions and understandings of pivotal moments within therapeutic relationships. The nurses were asked, in a series of one-to-one interviews, to consider relationships with clients that they would themselves describe as therapeutic and meditate on those moments at which everything seemed to change and the relationship became qualitatively different. Among the factors the nurses reported as being significant were empathy, uniqueness, meaning and purpose, and appropriate self-disclosure (although many of those terms may require clarification). This paper will consider the implications of these and others for nursing practice and the identity of psychiatric nursing practice. [ABSTRACT FROM AUTHOR]

Andropogon gayanus(gamba grass) is an introduced pasture grass that threatens Australia's tropical savannas by modifying fire regimes and species composition. To understand the establishment requirements ofA. gayanus, we undertook a field experiment to determine the effect of canopy cover and ground layer disturbance on seedling emergence and survival. Seed was sown under three canopy treatments (undisturbed, artificial canopy gap, and natural canopy gap) and under three ground layer treatments (Control, Vegetation disturbed, and Soil disturbed). Results have shown thatA. gayanuscan establish and survive regardless of canopy cover or ground disturbance, although such site disturbances will increase establishment success. Disturbance of both the overstorey canopy and the ground layer increasedA. gayanusemergence, whereas seedling survival to 12 mo after seed sowing was affected by ground layer disturbance alone. Disturbance of the canopy increased light transmission, which may have promoted germination. Ground layer disturbance may also have increased light transmission and suitable sites for establishment, and reduced competition for resources, such as water and nutrients. The ability ofA. gayanusto spread along disturbed areas, establish in relatively undisturbed savannas, and resprout after fire within 6 mo after seedling emergence suggests that this species will become increasingly widespread in Australia's tropical savannas. Its control is urgently required. [ABSTRACT FROM AUTHOR]

Abstract For a new diploid or homoploid hybrid species to become established, it must diverge ecologically from parental genotypes. Otherwise the hybrid neospecies will be overcome by gene flow or competition. We initiated a series of experiments designed to understand how the homoploid hybrid species, Helianthus paradoxus , was able to colonize salt marsh habitats, when both of its parental species (H. annuus ×H. petiolaris ) are salt sensitive. Here, we report on the results of a quantitative trait locus (QTL) analysis of mineral ion uptake traits and survivorship in 172 BC2 hybrids between H. annuus and H. petiolaris that were planted in H. paradoxus salt marsh habitat in New Mexico. A total of 14 QTLs were detected for mineral ion uptake traits and three for survivorship. Several mineral ion QTLs mapped to the same position as the survivorship QTLs, confirming previous studies, which indicated that salt tolerance in Helianthus is achieved through increased Ca uptake, coupled with greater exclusion of Na and related mineral ions. Of greater general significance was the observation that QTLs with effects in opposing directions were found for survivorship and for all mineral ion uptake traits with more than one detected QTL. This genetic architecture provides an ideal substrate for rapid ecological divergence in hybrid neospecies and offers a simple explanation for the colonization of salt marsh habitats by H. paradoxus . Finally, selection coefficients of +0.126, -0.084 and -0.094 for the three survivorship QTLs, respectively, are sufficiently large to account for establishment of new, homoploid hybrid species. [ABSTRACT FROM AUTHOR]

New crystallographic structures of the response regulator CheY in association with CheA124–257, its binding domain in the kinase CheA, have been determined. In all crystal forms, the molecular interactions at the heterodimer interface are identical. Soaking experiments have been performed on the crystals using acetyl phosphate as phosphodonor to CheY. No phosphoryl group attached to Asp57 of CheY is visible from the electron density, but the response regulator in the CheY- CheA124–257 complex may have undergone a phosphorylation- dephosphorylation process. The distribution of water mole- cules and the geometry of the active site have changed and are now similar to those of isolated CheY. In a second soaking experiment, imido-diphosphate, an inhibitor of the phosphorylation reaction, was used. This compound binds in the vicinity of the active site, close to the N-terminal part of the first α-helix. Together, these results suggest that the binding of CheY to CheA124–257 generates a geometry of the active site that favours phosphorylation and that imido- diphosphate interferes with phosphorylation by precluding structural changes in this region. [ABSTRACT FROM AUTHOR]

BSTRACT: A lumped, in time and space, model of stream-aquifer interactions is developed. The model is based upon mass balance and ancillary phenomenological equations that can evaluate changes in streamflow and groundwater quantity and quality. The model is applied to the Santa Margarita River, San Diego County, California to assess the impacts of proposed discharges of reclaimed wastewater on streamflows and underlying groundwaters. The model is relatively simple and economical to apply, thus minimizing analysis costs. [ABSTRACT FROM AUTHOR]

Attempts to assess the value of transference and ofcounter-transference experiences. Confusion of patient aboutpersonal identity; History of the separation of William Desmondfrom his wife; Physical separation of husband and wife.

A 3-month-old boy was admitted with failure to thrive and persistent fevers. During a 4 month hospitalization for treatment of suspected sepsis, persistent purulent nasal discharge developed. Biopsies of his nasal mucosa on 3 separate occasions disclosed thinned respiratory epithelium and a complete absence of cilia when examined by electron microscopy (EM). Despite an initial granulocytopenia and a wide range in T-cell numbers, he did not show any evidence of lower respiratory tract infection. A tracheal biopsy process for EM demonstrated normal ciliated epithelium. This patient appears to have an unrecognized syndrome of normal tracheal cilia but absent nasal cilia. [ABSTRACT FROM AUTHOR]