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The adsorption of dopants at the surface of 5CB has been studied using neutron reflection. The dopants were versions of 11OCB with partly fluorinated chains, and the 5CB was interfaced with air or with silica treated with fluorocarbon or hydrocarbon coatings. At the air interface, the F17-11OCB adsorbed homeotropically, and the amount increased on cooling into the nematic phase of 5CB. At low temperatures, the adsorption from the nematic phase appeared to saturate at a bilayer. At the solid interfaces, there was some evidence for a thin planar layer at the surface, but most of the adsorbed dopant was in the form of diffuse layers. In both cases, an increase in dopant concentration caused higher adsorbed amounts. For F17-11OCB, the amount absorbed was much greater for a fluorinated coating as opposed to a hydrocarbon-coated surface. Also no adsorption of the F3-11OCB could be detected, suggesting that the adsorption process is driven by the oleophobic effect. The results demonstrate that it is possible to manipulate surface properties of liquid crystals using surfactant-like dopants.

Stable suspensions of gold nanorods in 4-cyano-4′-pentylbiphenyl (5CB) have been prepared by capping the nanoparticles with polyethylene glycol (PEG). Small angle X-ray scattering has been used to characterize the orientational order of the gold nanorods and the properties of any aggregates. It was found that the nanorods had a very high degree of orientational order with respect to the director of the 5CB matrix and this could be redirected by an applied electric field at 2kHz. Two different PEG molecular weights were investigated and it was found that the lower (1.9kDa) gave exceptionally high order parameters, above 0.9.

The structures of polymer brushes under confinement were measured using a combination of neutron reflectivity and a surface force type apparatus. The samples were either poly(ethylene oxide), PEO, used to investigate the effect of the grafting density or poly(acrylic acid), PAA, used to determine the effect of charge on the structure of a polymer brushes under confinement. Without confinement both PEO and PAA brushes are found to be highly swollen with water, >50% v/v, with the expected parabolic brush structure. Compression of the PEO brushes with as little as 0.5 bar of confinement is found experimentally to reduce the brush to a polymer block of uniform density that is significantly dehydrated

SUMMARY Background Patients on haemodialysis have been identified as high-risk for medication discrepancies and adverse drug events. Medication reconciliation is an important patient safety initiative to prevent adverse drug events. The primary objective of our study was to determine the number and types of medication discrepancies and drug therapy problems (DTPs) identified in patients on haemodialysis. Our second objective was to assess the potential clinical impact and severity of all unintentional medication discrepancies identified. Methods Patients in an academic haemodialysis unit were interviewed to obtain a best possible medication history (BPMH) between May and August 2010. The BPMH was documented and discrepancies were identified, classified and resolved with the interprofessional team. An interprofessional panel conducted a discrepancy clinical impact assessment for potential adverse drug events. Results Two hundred and twenty-eight patients on haemodialysis were interviewed and 512 discrepancies were identified for 151 patients (3.4 discrepancies per patient). Of these, 174 (34%) were undocumented intentional discrepancies and 338 (66%) were unintentional discrepancies. The unintentional discrepancies were classified as 21% omissions, 36% commissions and 43% incorrect dose/frequency. Most drug therapy problems were related to patient taking a medication that was not indicated (25%), medication required but patient not taking (25%), patient not willing to take the medication as prescribed (28%) or incorrect dosing of a drug (20%). Overall, 6% of discrepancies were classified as clinically significant potential adverse drug events. Conclusion Medication discrepancies appear to be common in patients on haemodialysis. Formal interprofessional medication reconciliation practice models are essential to identify discrepancies and prevent patients from experiencing adverse drug events.

The structure and phase behavior of colloidal solutions of monodisperse rod-shaped micelles, of different lengths (ca. 300–2100 nm) and formed from poly(ferrocenylsilane)-block-polyisoprene (PFS-b-PI) diblock copolymers, have been investigated using synchrotron small-angle X-ray scattering. The dimensions of the crystalline PFS core, solvated PI corona, and the overall radial polydispersity were measured, and relationships between the characteristics of the constituent copolymers and the internal structure of the self-assembled micelles have been established. In addition, the effects of micelle length, length distribution, concentration, composition, and block length on the liquid crystalline phase behavior of the micelles have been determined. It was found that micelle dispersions exist in three distinct phases: isotropic, nematic, and hexagonally packed, depending predominantly on their concentration and aspect ratio. The results have also highlighted the importance of the coronal composition and struct...

Warfarin is frequently used in the hemodialysis (HD) population for atrial fibrillation (AF) and venous thromboembolism (VTE); however, there is insufficient evidence to support this practice. Given that HD patients have 3 - 10 times the risk for both stroke and bleeding than the general population, anticoagulation in these patients is controversial. Time in therapeutic range (TTR) is accepted as a surrogate outcome of clinical effectiveness and safety of warfarin. The primary objective of this study was to evaluate TTR in an HD population. A 6-year retrospective chart review was performed in 46 HD patients on warfarin (target international normaized ratio (INR)=2-3). One year of patient data was collected, which included weekly INRs, demographics and clinical outcomes. TTR was calculated using the Rosendaal and fraction of INRs in range methods. The mean TTR using the Rosendaal and fraction of INRs in range method was 49.2±14.6% and 44.2±13.5%, respectively. Patients were 3 times more likely to be below target than above it, suggesting they were more often at risk of inadequate efficacy rather than toxicity. There were 9 serious bleeding and 9 thrombotic events; these occurred in patients with a TTR

Individual colloids often carry a charge as a result of the dissociation (or adsorption) of weakly-ionized surface groups. The magnitude depends on the precise chemical environment surrounding a particle, which in a concentrated dispersion is a function of the colloid packing fraction $\eta$. Theoretical studies have suggested that the effective charge $Z_{\rm{eff}}$ in regulated systems could, in general, decrease with increasing $\eta$. We test this hypothesis for nonpolar dispersions by determining $Z_{\rm{eff}}(\eta)$ over a wide range of packing fractions ($10^{-5} \le \eta \le 0.3$) using a combination of small-angle X-ray scattering and electrophoretic mobility measurements. We find a complex dependence of the particle charge as a function of the packing fraction, with $Z_{\rm{eff}}$ initially decreasing at low concentrations before finally increasing at high $\eta$. We attribute the non-monotonic density dependence to a crossover from concentration-independent screening at low $\eta$, to a high packing fraction regime in which counterions outnumber salt ions and electrostatic screening becomes $\eta$-dependent. The efficiency of charge stabilization at high concentrations may explain the unusually high stability of concentrated nanoparticle dispersions which has been reported., Comment: 14 pages, 10 figures - published version

In this chapter we will discuss a one-step dissolution and fibre spinning method for chitin using ionic liquid 1-Ethyl-3-Methylimidazolium Acetate (EMImAc) as an environmentally benign solvent. A temperature-sensitive behaviour of chitin/EMImAc solution was observed during the fibre extrusion process. The regenerated chitin fibres were characterised through Fourier Transform Infrared Spectroscopy (FTIR), tensile testing, Scanning Electron Microscopy (SEM) and Wide Angle X-ray Diffraction (WAXD). Both molecular alignment and mechanical properties of chitin fibre increased as the draw ratio increased, confirmed by tensile testing results and the full width at half maximum (FWHM) of WAXD azimuthal scans. The regenerated chitin fibres with well controlled length, and good mechanical properties reported in this work could be potentially useful to explore the second most widely available polymer in nature for engineering and biomedical applications.

Here X-ray reflectivity has been used to determine the structure of liquid crystal monolayers for different cyanobiphenyl homologues supported on aqueous solutions of two different salt species. Sodium iodide induces homeotropic ordering for all of the monolayer forming liquid crystal homologues studied here, and forms a Stern layer of iodide ions at the liquid crystal cyano headgroup, similar to the case of lipids or surfactants supported on electrolyte solutions. The liquid crystal headgroups were also found to penetrate into the water surface when binding with iodide ions. Sodium bromide, however, does not form the same localisation of ions close to a liquid crystal monolayer, and instead appears to produce no noticeable change in the scattering length density of the liquid crystal monolayer compared to pure water. However, on further compression the X-ray reflectivity dramatically changes, revealing the emergence of the so-called “trilayer” structure for 5CB and 8CB. This transition occurs at a lower areal density for sodium bromide than for pure water, and unlike for the uncompressed film, a layer of bromide ions was found at the trilayer-water interface.

The chemotherapeutic Parthenolide is an exciting new candidate for the treatment of acute lymphoblastic leukemia, but like many other small-molecule drugs, it has low aqueous solubility. As a consequence, Parthenolide can only be administered clinically in the presence of harmful cosolvents. Accordingly, we describe the synthesis, characterization, and testing of a range of biocompatible triblock copolymer micelles as particle-based delivery vectors for the hydrophobic drug Parthenolide. The drug-loaded particles are produced via an emulsion-to-micelle transition method, and the effects of introducing anionic and cationic surface charges on stability, drug sequestration, biocompatibility, and efficacy are investigated. Significantly, we demonstrate high levels of efficacy in the organic solvent-free systems against human mesenchymal stem cells and primary T-acute lymphoblastic leukemia patient cells, highlighting the effectiveness of the delivery vectors for the treatment of acute lymphoblastic leukemia.

Light-induced shape transformations represent a fundamental step towards the emergence of adaptive materials exhibiting photomechanical behaviours. Although a range of covalent azobenzene-based photoactive materials has been demonstrated, the use of dynamic photoisomerization in mesostructured soft solids involving non-covalent co-assembly has received little attention. Here we prepare discrete micrometre-sized hydrated particles of a hexagonally ordered polyelectrolyte-surfactant mesophase based on the electrostatically induced co-assembly of poly(sodium acrylate) (PAA) and trans-azobenzene trimethylammonium bromide (trans-azoTAB), and demonstrate unusual non-equilibrium substrate-mediated shape transformations to complex multipodal microarchitectures under continuous blue light. The microparticles spontaneously sequester molecular dyes, functional enzymes and oligonucleotides, and undergo self-division when transformed to the cis state under UV irradiation. Our results illustrate that weak bonding interactions in polyelectrolyte-azobenzene surfactant mesophases can be exploited for photo-induced long-range molecular motion, and highlight how dynamic shape transformations and autonomous division can be activated by spatially confining azobenzene photomechanics in condensed microparticulate materials.

Background: National guidelines recommend using anemia management protocols to guide treatment. The objective of this study was to determine if an anemia management protocol would improve hemoglobin (Hgb) indices in hemodialysis patients and to measure whether the protocol would reduce the use and cost of darbepoetin alfa (DBO) and intravenous (IV) iron in hemodialysis patients. Methods: An anemia management protocol was created and implemented for hemodialysis patients at our institution. A retrospective observational review of the use of DBO and IV iron as well as changes in Hgb, transferrin saturation and ferritin in 174 patients was conducted 6 months before and after implementation of the anemia protocol. Results: The number of Hgb measurements in the target range increased from 44.3 to 46.0% (p = 0.48) after protocol implementation. The mean weekly dose of DBO was reduced from 34.56 ± 31.12 to 31.11 ± 28.64 μg post-protocol implementation (p = 0.011), which translated to a cost savings of USD 41,649 over 6 months. The mean monthly IV iron dose also decreased from 139.56 ± 98.83 to 97.65 ± 79.05 mg (p < 0.005), a cost savings of USD 18,594 over the same time period. Conclusion: The use of an anemia management protocol resulted in the deprescribing of DBO and iron agents while increasing the number of patients in the target Hgb range, which led to significant cost savings in the treatment of anemia.

We will discuss colloid suspensions of pigments and compare their electro-optic properties with those of traditional dyed low molecular weight liquid crystal systems. There are several potential advantages of colloidal suspensions over low molecular weight liquid crystal systems: a very high contrast because of the high orientational order parameter of suspensions of rod shaped nano-particles, the excellent light fastness of pigments as compared to dyes and high colour saturations resulting from the high loading of the colour stuff. Although a weak `single-particle' electro-optic response can be observed in dilute suspensions, the response is very much enhanced when the concentration of the particles is sufficient to lead to a nematic phase. Excellent stability of suspensions is beneficial for experimental observation and reproducibility, but it is a fundamental necessity for display applications. We therefore discuss a method to achieve long term stability of dispersed pigments and the reasons for its success. Small angle X-ray scattering was used to determine the orientational order parameter of the suspensions as a function of concentration and the dynamic response to an applied electric field. Optical properties were investigated for a wide range of pigment concentrations. Electro-optical phenomena, such as field-induced birefringence and switching, were characterised. In addition, mixtures of pigment suspensions with small amounts of ferro uids show promise as future magneto-optical materials.

We have developed a unique surface force type apparatus that allows direct measurements of the structure of a polymer layer under a confining pressure using neutron reflection. We have used this device to study the structure and the mechanical properties of a water swollen poly(styrenesulfonic acid) (PSSA) and poly(allylamine) PAH polyelectrolyte multilayer on silicon under confining pressures. A multilayer of 23 bilayers (60 nm) in thickness and terminated with a PAH layer swells to about 21% (v/v) of H2O. When the layer is then confined between a flexible plastic film and the silicon substrate, increased confining pressure gradually decreases the amount of water in the multilayer until, at 5 bar, only 10% of H2O remains. For a layer of the same number of bilayers but terminated with PSSA, the layer swells to about 28% of water, but between a confining pressure of 0–1, this is reduced to 16%, after which higher confining pressures do not lead to changes in hydration. The bulk salt concentration does not ...

Amphiphilic carbosilane dendrimers with novel architectural layout have been synthesized. These dendrimers contain peripheral groups consisting of covalently bound promesogenic fragments and hydrophilic (oligoethyleneglycolic) linkages which are connected to a carbosilane core in two distinct ways: as spacer or as tail arrangement. Such molecules have a block structure where the hydrophilic and hydrophobic blocks are distributed within the dendrimer forming layers of different polarity. The hydrophilic layer is either enclosed between two hydrophobic parts of the molecule or is situated on the periphery. The synthetic strategy for achieving these structures is described. The interfacial properties of the dendrimers were studied and the influence of the dendritic structure’s organization on the Langmuir film formation process is assessed.

We describe a new class of negative Poisson’s ratio (NPR) open cell PU–PE foams produced by blocking the shape memory effect in the polymer. Contrary to classical NPR open cell thermoset and thermoplastic foams that return to their auxetic phase after reheating (and therefore limit their use in technological applications), this new class of cellular solids has a permanent negative Poisson’s ratio behavior, generated through multiple shape memory (mSM) treatments that lead to a fixity of the topology of the cell foam. The mSM-NPR foams have Poisson’s ratio values similar to the auxetic foams prior their return to the conventional phase, but compressive stress–strain curves similar to the ones of conventional foams. The results show that by manipulating the shape memory effect in polymer microstructures it is possible to obtain new classes of materials with unusual deformation mechanisms., peer-reviewed

This paper presents a detailed analysis of the structure of the hexagonal phase of poly(ferrocenylsilane) (PFS)-based cylindrical micelles found at concentrations above ca. 5 wt. % in non-polar solvents such as decane. Small-angle X-ray scattering indicated that the hexagonal order is not long-range. In all samples, deviations in the lower order peak positions were observed with respect to those expected for a perfect hexagonal lattice, with the degree of deviation correlating with micelle length. Furthermore, analysis of the peak shapes and peak widths suggests that the phase possesses intermediate translational order similar. to the hexatic phase. The observed features can be reproduced by amending Hosemann’s paracrystal theory to include a distribution of lattice parameters to model well and poorly condensed regions. It is proposed that this distribution arises due to the bending and intertwining of individual micelles in a hexagonal lattice, resulting in a kinetically trapped phase that is initially neither perfectly hexagonal nor canonically hexatic but which anneals over time towards a perfect hexagonal lattice.

Cylindrical block copolymer micelles have shown considerable promise in various fields of biomedical research. However, unlike spherical micelles and vesicles, control over their dimensions in biologically relevant solvents has posed a key challenge that potentially limits in depth studies and their optimization for applications. Here, we report the preparation of cylindrical micelles of length in the wide range of 70 nm to 1.10 μm in aqueous media with narrow length distributions (length polydispersities1.10). In our approach, an amphiphilic linear-brush block copolymer, with high potential for functionalization, was synthesized based on poly(ferrocenyldimethylsilane)-b-poly(allyl glycidyl ether) (PFS-b-PAGE) decorated with triethylene glycol (TEG), abbreviated as PFS-b-(PEO-g-TEG). PFS-b-(PEO-g-TEG) cylindrical micelles of controlled length with low polydispersities were prepared in N,N-dimethylformamide using small seed initiators via living crystallization-driven self-assembly. Successful dispersion of these micelles into aqueous media was achieved by dialysis against deionized water. Furthermore, B-A-B amphiphilic triblock comicelles with PFS-b-poly(2-vinylpyridine) (P2VP) as hydrophobic "B" blocks and hydrophilic PFS-b-(PEO-g-TEG) "A" segments were prepared and their hierarchical self-assembly in aqueous media studied. It was found that superstructures formed are dependent on the length of the hydrophobic blocks. Quaternization of P2VP was shown to cause the disassembly of the superstructures, resulting in the first examples of water-soluble cylindrical multiblock comicelles. We also demonstrate the ability of the triblock comicelles with quaternized terminal segments to complex DNA and, thus, to potentially function as gene vectors.

The lack of multivariate methods for decoding the representational content of interregional neural communication has left it difficult to know what information is represented in distributed brain circuit interactions. Here we present Multi-Connection Pattern Analysis (MCPA), which works by learning mappings between the activity patterns of the populations as a factor of the information being processed. These maps are used to predict the activity from one neural population based on the activity from the other population. Successful MCPA-based decoding indicates the involvement of distributed computational processing and provides a framework for probing the representational structure of the interaction. Simulations demonstrate the efficacy of MCPA in realistic circumstances. Applying MCPA to fMRI data shows that interactions between visual cortex regions are sensitive to information that distinguishes individual natural images, suggesting that image individuation occurs through interactive computation across the visual processing network. MCPA-based representational similarity analyses (RSA) results support models of error coding in interactions among regions of the network. Further RSA analyses relate the non-linear information transformation operations between layers of a computational model (HMAX) of visual processing to the information transformation between regions of the visual processing network. Additionally, applying MCPA to human intracranial electrophysiological data demonstrates that the interaction between occipital face area and fusiform face area contains information about individual faces. Thus, MCPA can be used to assess the information represented in the coupled activity of interacting neural circuits and probe the underlying principles of information transformation between regions.

Self-assembled “cross” architectures are well-known in biological systems (as illustrated by chromosomes, for example); however, comparable synthetic structures are extremely rare. Herein we report an in depth study of the hierarchical assembly of the amphiphilic cylindrical P–H–P triblock comicelles with polar (P) coronal ends and a hydrophobic (H) central periphery in a selective solvent for the terminal segments which allows access to “cross” supermicelles under certain conditions. Well-defined P–H–P triblock comicelles M(PFS-b-PtBA)-b-M(PFS-b-PDMS)-b-M(PFS-b-PtBA) (M = micelle segment, PFS = polyferrocenyldimethylsilane, PtBA = poly(tert-butyl acrylate), and PDMS = polydimethylsiloxane) were created by the living crystallization-driven self-assembly (CDSA) method. By manipulating two factors in the supermicelles, namely the H segment-solvent interfacial energy (through the central H segment length, L1) and coronal steric effects (via the PtBA corona chain length in the P segment, L2 related to the degree of polymerization DP2) the aggregation of the triblock comicelles could be finely tuned. This allowed a phase-diagram to be constructed that can be extended to other triblock comicelles with different coronas on the central or end segment where “cross” supermicelles were exclusively formed under predicted conditions. Laser scanning confocal microscopy (LSCM) analysis of dye-labeled “cross” supermicelles, and block “cross” supermicelles formed by addition of a different unimer to the arm termini, provided complementary characterization to transmission electron microscopy (TEM) and dynamic light scattering (DLS) and confirmed the existence of these “cross” supermicelles as kinetically stable, micron-size colloidally stable structures in solution.

The intriguing twist-bend nematic (NTB) phase is formed, primarily, by liquid crystal dimers having odd spacers. Typically, the phase is preceded by a nematic (N) phase via a weak first-order transition. Our aim is to obtain dimers where the NTB phase is formed directly from the isotropic (I) phase via a strong first-order phase transition. The analogy between such behaviour and that of the smectic A (SmA)–N–I sequence suggests that this new dimer will require a short spacer. This expectation is consistent with the prediction of a molecular field theory, since the decrease in the spacer length results in an increase in the molecular curvature. A vector of odd dimers based on benzoyloxybenzylidene mesogenic groups with terminal ethoxy groups has been synthesised with spacers composed of odd numbers of methylene groups. Spacers having 5, 7, 9 and 11 methylene groups are found to possess the conventional phase sequence NTB–N–I; surprisingly, for the propane spacer, the NTB phase is formed directly from the I phase. The properties of these dimers have been studied with care to ensure that the identification of the NTB phase is reliable.

The interpenetration of two polymer brushes on approaching flat surfaces has been investigated. When compacting polymer brushes with an asymmetric charge on each surface, one neutral and the other weakly charged, we find that the brush interpenetration becomes a parameter that can be controlled by the pH of the hydrating solution. The switching between high and low degrees of brush interpenetration was investigated with numerical self-consistent field theory (nSCF) and experimentally using a sample environment which combines neutron reflectometry with a surface force type apparatus. Initially, a pair of uncharged poly(ethylene oxide), PEO, brushes are examined, where one of the brushes is deuterated to distinguish it from a hydrogenous counter-part. We find in both nSCF and these experiments that there is no significant overlap between the brushes as both compact into polymer blocks with little hydration. However, when a weak polyelectrolyte poly(2-(dimethylamino)ethyl methacrylate), PDMAEMA, brush is confined against a deuterated neutral PEO brush and the pH of the hydrating solution is below the polycation’s pKa of 7.5, then the presence of charged groups on the PDMAEMA allows significant interpenetration to occur between the two polymer brushes on contact. This interpenetration remains once the polymer brushes dehydrate due to the confining pressure that is applied. Raising the pH to a value above the pKa, removes the charges from the polyelectrolyte brush resulting in little to no interpenetration between the two brushes. Therefore, by simply adjusting the pH of the hydrating solution the interpenetration state between polymer brush pairs can be switched when one brush is a weak polyelectrolyte. Since polymer brushes are widely investigated and used to reduce friction between solid surfaces, this effect may have significant implications in the design and operation of polymer brushes with controllable friction properties.

We undertook this study to characterize the epidemiology of acute kidney injury (AKI) in Canadian critical care units. We aimed to identify predictors of mortality for patients diagnosed with AKI.We conducted a prospective cohort study of consecutive patients admitted to critical care units at five Canadian hospitals over a 30-day period. Each patient was followed until hospital discharge or for a maximum of 30 days. The serum creatinine criteria for the Acute Kidney Injury Network (AKIN-SCr) system were used to identify, classify, and characterize patients who developed AKI. We used multivariable logistic regression to predict 30-day mortality among patients with AKI.We identified 603 patients, 161 (26.7%) of whom developed AKI. Compared to patients without AKI, those with AKI were more likely to die (29.2% vs 8.6%, P0.001). The risk of death increased with increasing AKIN-SCr stage (P0.001). In all, 19 patients (11.8% of those with AKI) commenced dialysis a median of one day (interquartile range, one to two days) after AKI diagnosis. At AKI diagnosis, the blood urea nitrogen (BUN) level (adjusted odds ratio [OR] 1.68, 95% confidence interval [CI] 1.01 to 2.79/10 mmol·L(-1)) and serum bicarbonate (adjusted OR 0.88, 95% CI 0.81 to 0.95/1 mmol·L(-1)) were associated with 30-day mortality and predicted death with an area under the receiver-operating characteristic curve of 0.79 (95% CI 0.71 to 0.86).Acute kidney injury is a common complication of critical illness in Canada. The development of even the mildest stage of AKI is associated with a substantially higher risk of death. At AKI diagnosis, routine clinical data may be helpful for predicting adverse outcomes.

Tuberculosis is an important issue for nephrologists caring for dialysis patients. Because dialysis patients are immunocompromised, they are at higher risk for reactivation of latent tuberculosis, and they frequently have atypical presentation. Furthermore, hemodialysis units may foster rapid spread of active pulmonary tuberculosis. The diagnosis of active pulmonary tuberculosis still depends on detection of organisms by smear and culture. Newer nucleic acid detection techniques are more sensitive and specific. Nephrologists should remember that nonspecific presentation of tuberculosis including fever, weight loss, and adenopathy are more common in dialysis patients than in the general population, and diagnosis may require biopsy of extrapulmonary tissue. Detection of latent tuberculosis in dialysis patients should only be undertaken if treatment is planned. Generally, this should apply only to potential transplant candidates and younger dialysis patients with longer life expectancy. Tuberculin skin test is very insensitive in dialysis patients, and false-positives occur in patients born in countries where Bacillus Calmette-Guerin vaccine has been used. Blood tests using stimulation of gamma interferon have been shown to be more sensitive tests of latent tuberculosis and may be used in conjunction with tuberculin skin tests.

For the first time a series of anionic surfactant ionic liquids (SAILs) has been synthesized based on organic surfactant anions and 1-butyl-3-methyl-imidazolium cations. These compounds are more environmentally friendly and chemically tunable as compared to other common ionic liquids. A detailed investigation of physicochemical properties highlights potential applications from battery design to reaction control, and studies into aqueous aggregation behavior, as well as structuring in pure ILs, point to possible uses in electrochemistry.

Acute kidney injury (AKI) is an increasingly common problem among hospitalized patients. Patients who survive an AKI-associated hospitalization are at higher risk of de novo and worsening chronic kidney disease, end-stage kidney disease, cardiovascular disease, and death. For hospitalized patients with dialysis-requiring AKI, outpatient follow-up with a nephrologist within 90 days of hospital discharge has been associated with enhanced survival. However, most patients who survive an AKI episode do not receive any follow-up nephrology care. This narrative review describes the experience of two new clinical programs to care for AKI patients after hospital discharge: the Acute Kidney Injury Follow-up Clinic for adults (St. Michael's Hospital and University Health Network, Toronto, Canada) and the AKI Survivor Clinic for children (Cincinnati Children's Hospital, USA).MEDLINE, PubMed, ISI Web of Science.These two ambulatory clinics have been in existence for close to two (adult) and four (pediatric) years, and were developed separately and independently in different populations and health systems. The components of both clinics are described, including the target population, referral process, medical interventions, patient education activities, and follow-up schedule. Common elements include targeting patients with KDIGO stage 2 or 3 AKI, regular audits of the inpatient nephrology census to track eligible patients, medication reconciliation, and education on the long-term consequences of AKI.Despite the theoretical benefits of post-AKI follow-up and the clinic components described, there is no high quality evidence to prove that the interventions implemented in these clinics will reduce morbidity or mortality. Therefore, we also present a plan to evaluate the adult AKI Follow-up Clinic in order to determine if it can improve clinical outcomes compared to patients with AKI who do not receive follow-up care.Follow-up of AKI survivors is low, and this review describes two different clinics that care for patients who survive an AKI episode. We believe that sharing the experiences of the AKI Follow-up Clinic and AKI Survivor Clinic provide physicians with a feasible framework to implement their own clinics, which may help AKI patients receive outpatient care commensurate with their high risk status.L’insuffisance rénale aiguë (IRA) est un problème de plus en plus fréquent chez les patients hospitalisés. Ceux d’entre eux qui survivent à un épisode d’IRA courent un risque élevé de développer une insuffisance rénale chronique et des maladies cardiovasculaires ou d’aggraver leur état vers l’insuffisance rénale terminale et donc, la mort. Chez les patients hospitalisés pour insuffisance rénale aiguë nécessitant une hémodialyse, un taux de survie accru a été associé à un suivi par un néphrologue dans les 90 jours suivant la sortie de l’hôpital. Cependant, la majorité de ces patients ne bénéficient d’aucun suivi en néphrologie post-hospitalisation. La présente revue narrative s’attarde à décrire l’expérience de deux nouveaux programmes cliniques qui prennent en charge les patients après leur sortie de l’hôpital à la suite d’un épisode d’IRA. Il s’agit des programmes de l’« Acute Kidney Injury Follow-up Clinic » des hôpitaux St. Micheal et UHN de Toronto, et de la clinique pédiatrique « AKI Survivor Clinic for children » de l’hôpital pour enfants de Cincinnati, aux États-Unis.MEDLINE, PubMed, ISI le web des sciences.Ces cliniques ambulatoires, qui existent depuis près de deux ans (clinique pour adultes) et de quatre ans (clinique pédiatrique) se sont développées séparément et de façon indépendante pour des populations différentes, dans des systèmes de santé différents. Les constituants de ces deux cliniques se distinguent par l’identification de la population ciblée, le processus de présentation, les interventions médicales, les activités de sensibilisation auprès des patients et leur calendrier de suivi. Les parties communes incluent le recrutement de patients atteints d’IRA de stades 2 et 3 quant aux chances de l’amélioration globale de leurs résultats (KDIGO). Ce recrutement se fait par le passage en revue à intervalles réguliers des listes de patients hospitalisés aux unités néphrologiques afin d’identifier ceux qui sont admissibles au suivi. Ces parties communes incluent aussi un bilan comparatif des médicaments et la transmission d’informations sur les conséquences à long terme de l’insuffisance rénale aiguë.Malgré les bienfaits escomptés d’un suivi post-IRA et, les éléments cliniques décrits plus haut, il n’existe aucune preuve concrète que les procédures mises en œuvre dans ces programmes réduiront la morbidité ou la mortalité associées à la maladie. Par conséquent, nous présentons également un plan d’évaluation de la clinique pour adultes en suivi post-IRA afin de déterminer si son programme peut améliorer les résultats cliniques de ses patients en comparaison avec les patients ne recevant pas ce suivi.De façon générale, peu de patients ayant survécu à un épisode d’IRA reçoivent un suivi adéquat post-hospitalisation. Cette revue présente deux cliniques offrant ce suivi. Nous pensons que le partage de leurs expériences respectives peut poser un cadre réalisable aux médecins traitants qui souhaiteraient mettre sur pied leurs propres cliniques, afin d’offrir à leurs patients un suivi en externe répondant adéquatement à leur état de santé précaire.

The self-assembly of block copolymers in selective solvents represents a powerful approach to functional core-shell nanoparticles. Crystallization of the core can play a critical role in directing self-assembly toward desirable, nonspherical morphologies with low mean interfacial curvature. Moreover, epitaxial growth processes have been implicated in recent advances that permit access to monodisperse cylinders, cylindrical block comicelles with segmented cores and/or coronas, and complex hierarchical architectures. However, how the core-forming block crystallizes in an inherently curved nanoscopic environment has not been resolved. Herein we report the results of synchrotron small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS) studies of well-defined, monodisperse crystalline-coil polyisoprene-block-polyferrocenylsilane cylindrical micelles aligned in an electric field. WAXS studies of the aligned cylinders have provided key structural information on the nature of the PFS micelle core together with insight into the role of polymer crystallinity in the self-assembly of these and potentially related crystalline-coil block copolymers.

Symmetric fully liquid-crystalline triblock copolymers of various structures containing optically active mesogenic groups are for the first time synthesized via pseudoliving radical reversible addition-fragmentation chain-transfer polymerization. Their phase behavior and physicochemical and optical properties are studied. It is shown that, depending on composition, at low temperatures block copolymers can form at temperatures phase-separated structures caused by microsegregation of blocks of different chemical natures and that, with an increase in temperature, these structures can mix to form a cholesteric mesophase characterized by a helical supramolecular structure. A model illustrating the molecular packing of block copolymers with a phase-separated lamellar structure is advanced. The effect of the molecular structure of the block copolymers on their optical properties is discussed.

A comparative analysis of the structure and phase behavior of synthesized carbosilane amphiphilic LC dendrimers of the third generation containing mesogenic phenyl and oligo(ethylene glycol) fragments is performed. When phenol groups are replaced with oligo(ethylene glycol) moieties, the temperature interval of the existence of the LC phase in the mesogen-containing dendrimers decreases. The chemical nature of hydrophilic terminal groups is found to control the organization of dendrimers in the smectic mesophase. Structural models for their packing are proposed. Amphiphilic dendrimers are shown to form stable Langmuir films at the water/air interface. Surface-pressure-surface area-isotherms are constructed. The effect of the chemical nature of hydrophilic groups on the formation of a monolayer at the interface and on the packing density of dendrimer molecules in the monolayer is discussed.

BACKGROUND Uncontrolled hy-per-parathyroidism causes bone marrow fibrosis, leading to erythropoietin (EPO) resistance. Medical treatment with cinacalcet is effective in reducing plasma parathyroid hormone (PTH) levels, but its effect on darbepoetin dosing is unknown. METHODS AND AIMS We conducted a retrospective cohort study of 40 end-stage renal disease (ESRD) patients (age: 55 ± 14; mean ± SD; 21:male) who had at least 12 months of cinacalcet therapy. The distribution of renal replacement therapies were: 14 peritoneal dialysis, 18 conventional hemodialysis and 8 nocturnal hemodialysis. Standard dialysis related biochemical indices and medications used were recorded. The primary objective of the study was to ascertain the difference in darbepoetin responsiveness before and after 12 months of cinacalcet therapy. Our secondary objective was to determine if there was a relationship between the changes in PTH and darbepoetin requirement. RESULTS Overall, PTH levels decreased from 197.5 (151.8; 249.2) to 66.1 (41.2; 136.5) (median (25th;75th percentile)) pmol/l; p < 0.001. Cinacalcet dose increased from 30.0 ± 6 to 63 ± 25 mg/day, p < 0.05. Hemoglobin remained unchanged (116 ± 13 to 116 ± 13 g/l), while darbepoetin requirement decreased from 40 (20; 60) to 24 (19; 59) μg/week, p = 0.02. The remainder of the dialysis-related biochemistry (electrolytes, calcium, phosphate, iron status) and vitamin D use remained unchanged. A reduction in PTH level of greater than 30% was experienced by 82.5% (33/40) of our cohort. Among the responders, the fall in PTH and reduction darbepoetin requirement were related (R = -0.48, p = 0.004). CONCLUSIONS Reduction of PTH by cinacalcet is associated with a decrease in darbepoetin requirement. The interface between bone and bone marrow in uremia represents a critical step in red blood cell production which merits further investigation.

An unusual electro-optical behavior of colloidal suspensions of dichroic, elongated (rod-shaped) pigment particles is reported. These suspensions exhibit nematic liquid crystal order at low volume fraction of the suspended particles (

There is a need to develop high-performance cellulose fibers as sustainable replacements for glass fibers, and as alternative precursors for carbon filaments. Traditional fiber spinning uses toxic solvents, but in this study, by using dimethyl sulfoxide (DMSO) as a co-solvent with an ionic liquid, a novel high-performance fiber with exceptional mechanical properties is produced. This involves a one-step dissolution, and cost-effective route to convert high concentrations of low molecular weight microcrystalline cellulose into high stiffness cellulose fibers. As the cellulose concentration increases from 20.8 to 23.6 wt%, strong optically anisotropic patterns appear for cellulose solutions, and the clearing temperature (T c) increases from ≈100 °C to above 105 °C. Highly aligned, stiff cellulose fibers are dry-jet wet spun from 20.8 and 23.6 wt% cellulose/1-ethyl-3-methylimidazolium diethyl phosphate/DMSO solutions, with a Young's modulus of up to ≈41 GPa. The significant alignment of cellulose chains along the fiber axis is confirmed by scanning electron microscopy, wide-angle X-ray diffraction, and powder X-ray diffraction. This process presents a new route to convert high concentrations of low molecular weight cellulose into high stiffness fibers, while significantly reducing the processing time and cost.

Background: Since Mehta et al. reported the first successful use of regional citrate anticoagulation (RCA) for continuous renal replacement therapy (CRRT) in 1990, RCA is increasingly used for CRRT because it provides filter patency with minimal risk of bleeding. However, RCA has been associated with significant metabolic complications including hypocalcemia, hypernatremia, metabolic alkalosis, and citrate toxicity. Objective: To describe our experience with a newly implemented RCA protocol with acid citrate dextrose formula A (ACD-A) and intravenous calcium gluconate, for use with PrismaFlex CRRT in critically ill patients with acute kidney injury. Methods: A retrospective chart review was conducted from May 1, 2006, until May 1, 2007, in a 16-bed medical-surgical university-affiliated intensive care unit. Data collected included dialysis filter life, patient and circuit metabolic parameters, and units of packed red blood cells transfused. Results: Forty-eight patients received dialysis with citrate (n = 178 fitters). Circuit clotting occurred in 24% of all filters. Mean ± SD filter life was 38.4 ± 25.9 hours, and filter survival at 48 hours was 38.2%. Persistent metabolic alkalosis while on CRRT was identified in 6 of 45 (13.3%) patients. Mild hypocalcemia (ionized calcium Conclusions: We found that anticoagulation of PrismaFlex CRRT with ACD-A and intravenous calcium gluconate provided reasonable filter patency, but with minor metabolic complications. Close monitoring of electrolyte and acid–base balance is required to minimize metabolic derangements.

X-ray and neutron scattering investigations have been made on two series of liquid crystal dendrimers. The low generations (first to fourth) predominantly show smectic phases. The fifth generation shows a tendency to form columnar phases and two different types have been observed. The transition from smectic to columnar has been explained in terms of the distance between the dendritic core and the mesogenic units. As the generation number is increased, the distance increases until it becomes greater than the maximum length of the flexible spacers causing a change in molecular shape and the formation of columnar phases. Although the materials are nearly monodisperse, the small variation in the number of mesogens per molecule gives rise to some subtle structural effects. Two coexisting structures have been observed over large temperature ranges in some materials and small angle neutron scattering indicates that there is some microphase segregation which is a reversible function of temperature.

Amphiphilic carbosilane liquid-crystalline codendrimers with terminal mesogenic butoxybenzoate and phenolic groups have been synthesized for the first time. The structures and compositions of the synthesized codendrimers were characterized by NMR spectroscopy. The data from polarization optical microscopy, differential scanning calorimetry, and small-angle X-ray scattering demonstrated that all codendrimers possessed mesomorphic properties. They form thin (Langmuir) films at the water-air interface. The surface pressure-surface area isotherms were plotted. The Langmuir-Blodgett films of different thicknesses were obtained by the vertical dipping method on the solid substrate. The film structures were studied by grazing incidence X-ray diffraction analysis.

The first series of carbosilane liquid crystal codendrimers with groups of different polarity has been synthesized. The chemical structure of the newly synthesized materials and the composition of the codendrimers were studied by NMR spectroscopy and MALDI-TOF MS. It was found that the codendrimers tend to form stable Langmuir films at the air-water surface. The influence of composition and generation number on surface pressure-surface area isotherms and film stability was studied. Brewster angle microscopy confirmed the different phase behavior for monolayers of different codendrimer composition and generation number. It was found that side groups of fifth-generation codendrimers do not segregate, unlike those of lower generations. Langmuir-Blodgett films on solid substrates were obtained by the vertical dipping method. X-ray diffraction showed that the codendrimers with 75% of hydrophobic mesogenic terminal groups formed ordered layers parallel to the substrate.

Spectroscopic ellipsometry has been used to measure enhanced orientational ordering at the nematic–air interface of 8CB as the smectic A phase was approached by cooling from the isotropic phase. The depth profile of the orientational order has been estimated by calculating the ellipsometric parameters for a homeotropic uniaxial surface film on a uniaxial sub‐phase using the Abeles matrix method. This showed that the depth of the enhanced orientationally ordered region was ∼10 nm at 0.5°C above the nematic–smectic A transition. This is substantially less than the thickness of the region with surface enhanced smectic order as determined by neutron reflection and a model of the surface structure consistent with both sets of results is proposed.

Background: Acute kidney injury (AKI) complicates 15-20% of hospitalizations, and AKI survivors are at increased risk of chronic kidney disease and death. However, less than 20% of patients see a nephrologist within 3 months of discharge, even though a nephrologist visit within 90 days of discharge is associated with enhanced survival. To address this, we established an AKI Follow-Up Clinic and characterized the patterns of care delivered. Methods: We conducted a prospective time series study. All hospitalized patients who developed Kidney Disease Improving Global Outcomes (KDIGO) stage 2 or 3 AKI were eligible. The pre-intervention period consisted of electronic reminders to the nephrology consults and cardiovascular surgery services to refer to the AKI Follow-Up Clinic. In the post-intervention period, eligible patients were automatically scheduled into the AKI Follow-Up Clinic at discharge. The primary outcome was the percentage of KDIGO stages 2-3 AKI survivors assessed by a nephrologist within 30 days of discharge. Results: In the pre-intervention period, 8 of 46 patients (17%) were seen by a nephrologist within 30 days after discharge, and no additional patients were seen for 90 days. In the post-intervention period, 17 of 69 patients (25%) were seen by a nephrologist within 30 days after discharge (p = 0.36), with an additional 30 patients seen in 90 days (47 of 69, 68%, p < 0.001). The mean serum creatinine was 99 (SD 35) µmol/l prior to hospitalization and 133 (58) µmol/l at 3 months. Fifty-five of 79 patients (70%) received at least 1 medical intervention at their first AKI Follow-Up Clinic visit. Conclusions: An AKI Follow-Up Clinic with an automatic referral process increased the proportion of patients seen at 90 days, but not 30 days post discharge. Being seen in the AKI Follow-Up Clinic was associated with interventions in most patients. Future research is needed to evaluate the effect of the AKI Follow-Up Clinic on patient-centered outcomes, but physicians should be aware that AKI survivors may benefit from close outpatient follow-up and a multipronged approach to care similarly for other high-risk populations.

© 2015 American Chemical Society.This work reports on the preparation and characterization of natural composite materials prepared from bacterial cellulose (BC) incorporated into a gelatin matrix. Composite morphology was studied using scanning electron microscopy and 2D Raman imaging revealing an inhomogeneous dispersion of BC within the gelatin matrix. The composite materials showed controllable degrees of transparency to visible light and opacity to UV light depending on BC weight fraction. By adding a 10 wt % fraction of BC in gelatin, visible (= 550 nm) and UV (= 350 nm) transmittances were found to decrease by ∼35 and 40%, respectively. Additionally, stress transfer occurring between the gelatin and BC fibrils was quantified using Raman spectroscopy. This is the first report for a gelatin-matrix composite containing cellulose. As a function of strain, two distinct domains, both showing linear relationships, were observed for which an average initial shift rate with respect to strain of -0.63 ± 0.2 cm-1%-1 was observed, followed by an average shift rate of -0.25 ± 0.03 cm-1%-1. The average initial Raman band shift rate value corresponds to an average effective Youngs modulus of 39 ± 13 GPa and 73 ± 25 GPa, respectively, for either a 2D and 3D network of BC fibrils embedded in the gelatin matrix. As a function of stress, a linear relationship was observed with a Raman band shift rate of -27 ± 3 cm-1GPa-1. The potential use of these composite materials as a UV blocking food coating is discussed.

3D-printing, along with other additive manufacturing (AM) and rapid prototyping (RP) techniques, involves building up structures in a layer by layer fashion based upon a computer design file. Such techniques are well suited to the production of one-off, complex structures that would often be difficult to produce using traditional manufacturing methods. There has been rapid growth and interest in this field during recent years and a range of techniques are now available which make use of many common materials such as plastic, metal, wood and ceramic. However, relatively little has been done to develop AM using glass. Glass is usually printed at room temperature and requires a second step, the firing process, to achieve the final result. Depending on which 3D printing technique is used to produce the so called greenware and what support material surrounds the object during firing the surface finish and the bulk properties differ greatly. We will report different techniques and the physical properties (Young’s modulus, opacity and density) of glass generated by them.

In patients with severe acute kidney injury (AKI) but no urgent indication for renal replacement therapy (RRT), the optimal time to initiate RRT remains controversial. While starting RRT preemptively may have benefits, this may expose patients to unnecessary RRT. To study this, we conducted a 12-center open-label pilot trial of critically ill adults with volume replete severe AKI. Patients were randomized to accelerated (12 h or less from eligibility) or standard RRT initiation. Outcomes were adherence to protocol-defined time windows for RRT initiation (primary), proportion of eligible patients enrolled, follow-up to 90 days, and safety in 101 fully eligible patients (57 with sepsis) with a mean age of 63 years. Median serum creatinine and urine output at enrollment were 268 micromoles/l and 356 ml per 24 h, respectively. In the accelerated arm, all patients commenced RRT and 45/48 did so within 12 h from eligibility (median 7.4 h). In the standard arm, 33 patients started RRT at a median of 31.6 h from eligibility, of which 19 did not receive RRT (6 died and 13 recovered kidney function). Clinical outcomes were available for all patients at 90 days following enrollment, with mortality 38% in the accelerated and 37% in the standard arm. Two surviving patients, both randomized to standard RRT initiation, were still RRT dependent at day 90. No safety signal was evident in either arm. Our findings can inform the design of a large-scale effectiveness randomized control trial.

X‐ray diffraction studies are carried out in order to probe the smectic layer structure in liquid crystal devices filled with FLC mixture SCE8 and AFLC mixture CS4001, at a temperature just above the SmA∗–SmC∗ phase transtion. The data gathered are time‐resolved in synchronization with a bipolar voltage pulse applied across the device. The layers are observed to move dynamically and reversibly with voltage application and removal, giving evidence for temporary vertical chevron formation due to the electroclinic effect on a timescale consistent with this phenomenon.

Montmorillonite clay was treated with quaternary ammonium surfactants with 1-3 long chains of 10-18 carbons to form organoclays which can be suspended in non-aqueous solvents. The effects of surfactant chain length, number of long chains, and the properties of the solvent on the colloidal behavior of the surfactant coated clay plates were studied using small-angle X-ray scattering. The scattering data were modeled using a one-dimensional aggregation theory to describe the stacking of the clay plates. The plates self-organize into stacks with a reproducible basal spacing in the range of 30-50 A, and for each surfactant, the basal spacing falls into one of two preferred distances. We interpret this by considering that the surfactant layer on the clay has two strata, one being the polar near-clay headgroup region and the other the nonpolar alkane chain region. Polar solvents will swell the polar stratum preferentially while nonpolar solvents will swell the nonpolar stratum of the surfactant. As the nonpolar stratum is larger than the polar one, the nonpolar solvents increase the basal spacing between the clay plates more than the polar solvents. The number of long chains on the surfactant does not have an effect on the basal spacing, as the density of surfactant molecules on the surface is low enough to allow the unimpeded swelling of the chains. The one-dimensional aggregation theory can be used to determine the number of plates in a stack, but the effect of changing clay particle size or concentration is not as great as would be expected from this theory. This may be due to the formation of large-scale structures in the suspensions which prevent a true equilibrium stack size being attained.

End-stage renal disease (ESRD) is associated with a markedly increased cardiac calcification burden, as reflected by computed tomography scans of the heart. Nocturnal haemodialysis (NHD) is a novel form of renal replacement therapy which has multiple physiologic effects that may affect vascular calcification, including improvements in phosphate and uraemia control. The objective of the present study is the determination of the natural history of coronary calcification progression in patients converted to NHD, and the examination of the relationships between calcification risk factors and calcification progression in these patients.Thirty-eight ESRD patients were converted to NHD, and included in our observational cohort study. Coronary artery calcification scores (CACS) were documented at baseline and post-conversion (mean interscan duration 16+/-1 months). Other variables of interest included age, dialysis vintage, Framingham risk profile, phosphate binder and vitamin D usage, and plasma levels of calcium, phosphate and parathyroid hormone.Our cohort was stratified according to baseline calcification burden (minimal calcification: CACSor = 10 vs significant calcification: CACS10). Twenty-four patients had baseline CACSor = 10. These patients demonstrated no change in coronary calcification after 1 year of NHD (from 0.7+/-0.5 to 6+/-3, P = 0.1). Fourteen patients had higher initial CACS at baseline (1874+/-696), and demonstrated a non-significant 9% increase over 1 year to 2038+/-740 (P = 0.1). Plasma phosphate and calcium x phosphate product were significantly reduced, as were calcium-based phosphate binder and antihypertensive usage.Our study is the first to document CACS progression in a cohort of NHD patients. Further analysis of the effect of NHD on the physiology of cardiovascular calcification is required.