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This study investigates the potential of composite allotrope boron nitride nanobarbs (BNNBs) as nanoparticles for enhancing the thermal conductivity of nanofluids based on mixtures of ethylene glycol and propylene glycol with water.

Boron nitride nanotubes (BNNTs) will be one of the most important materials of this century. Recent synthetic advances have made BNNTs viable candidates for advanced multifunctional materials. Like carbon nanotubes and graphene, BNNTs and h-BN have extraordinary physical properties. Unlike CNTs, BNNTs have a wideband gap; they are piezoelectric, have neutron radiation shielding capability, and can withstand degradation up to 1000 °C. BNNTs could be the next big leap for nanocomposite advanced applications; however, significant scientific challenges must be addressed. Predominantly, large-scale synthesis techniques are immature. Production products require careful characterization, analysis, and purification. Impurities such as boron, amorphous BN, and h-BN lead to difficulty studying chemical modification and translation of BNNT properties. This review synthesizes relevant literature and state-of-the-art techniques regarding purification methods of BNNTs, classified as physical, chemical, and multi-step techniques and their applications. The review also discusses BNNT synthesis methods and future research directions.Graphical abstract

Discrete Co4S4 clusters can be reversibly crosslinked into redox-active frameworks using Janus bis-N-heterocyclic carbene (NHC) ligands.

A perfluorinated ionic liquid, 1-(perfluorohexyl)-3-methylimidazolium iodide, was synthesized via microwave reaction and compared to a non-fluorinated analog. Typically, the synthesis of fluorinated ionic liquids involves long reaction times and multiple steps. We have demonstrated a shortened synthesis and a more straightforward procedure, by using a microwave reactor for the microwave-assisted synthesis of 1-(perfluorohexyl)-3-methylimidazolium iodide. The addition of fluorinated alkyl chains on imidazolium ionic liquid cations increases the molecular free volume of the ionic liquid which is beneficial for increasing CO2 physisorption. Computational and experimental data shows an increased CO2 solubility and capacity for fluorinated ionic liquids. The perfluoroalkyl functionalized ionic liquid is characterized using 1H and 19F NMR spectroscopy, FTIR spectroscopy, and DSC. By DSC, a crystallization onset is near -31 °C and while the onset of the melting point between -30 and -17 °C.

Boron nitride nanotubes (BNNTs) and hexagonal boron nitride platelets (h-BNs) have received considerable attention for aerospace insulation applications due to their exceptional chemical and thermal stability. Presently, making BN nanomaterials compatible with polymer and composite matrices is challenging. Due to their inert and highly stable structure, h-BN and BNNTs are difficult to covalently functionalize. In this work, we present a novel sonochemical technique that enables covalent attachment of fluoroalkoxy substituents to the surface of BN nanomaterials in a controlled and metered process. Covalent functionalization is confirmed via colloidal stability analysis, FT-IR, and x-ray photoelectron spectroscopy (XPS).

Preparation of high-quality boron nitride nanotubes (BNNTs) from commercially available stock is critical for eventual industry adoption and to perform comprehensive experimental studies of BNNTs. Separation of hexagonal boron nitride (h-BN) and BNNTs is a significant challenge, and equally so, quantification of h-BN content in mixed samples is a major challenge due to their nearly identical properties. This work introduces a simple method of quantifying h-BN content in BNNTs based on FTIR analysis. Quantification is achieved by “spiking” a BNNT sample with pure nanoscale h-BN as an internal standard. To demonstrate the efficacy of the quantification technique two BNNT enrichment methods, surfactant wrapping and centrifugation, and a novel sonication-assisted isovolumetric filtration are introduced. FTIR spectra of enriched samples show clear trends throughout the processes. We propose and demonstrate that FTIR peak ratios of the transverse and buckling modes of mixed h-BN/BNNT samples can be used to calibrate and quantify h-BN content in any BNNT sample. Hopefully, this method enables as-received BNNTs to be quantifiably enriched from low purity commercial feedstocks, enabling future development and study of BNNTs and related technology.

A series of paramagnetic ionic liquids (PILs) based on N,N′-bis(alkyl)imidazolium bromotrichloroferrate(III), [(Cn)2Im][FeCl3Br] (Im = imidazole; Cn = ethyl, butyl, hexyl, octyl, decyl, dodecyl), was prepared and compared against the more traditional [CnC1Im][FeCl3Br] (C1 = methyl) analogs. Both series were extensively characterized by physical, chemical, and computational methods including differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), spectroscopy (FTIR and UV‐vis-NIR), magnetic susceptibility, surface tensiometry, density, and viscosity. The X-ray crystal structure of [(C12)2Im][FeCl3Br] was also obtained. Notably, all ionic liquids prepared in this study show short-term thermal stabilities exceeding 300 °C in air and have melting points equal to or lower than 25 °C, which is surprisingly low for ionic liquids containing symmetrical cations. In addition, all presented ionic liquids have relatively low viscosities allowing for easier transitioning into applications. Physical property trends are discussed.

Preparation of high-quality boron nitride nanotubes (BNNTs) from commercially available stock is critical for eventual industry adoption and to perform comprehensive experimental studies of BNNTs. Separation of hexagonal boron nitride (h-BN) and BNNTs is a significant challenge, and equally so, quantification of h-BN content in mixed samples is a major challenge due to their nearly identical properties. This work introduces a simple method of quantifying h-BN content in BNNTs based on FTIR analysis. Quantification is achieved by "spiking" a BNNT sample with pure nanoscale h-BN as an internal standard. To demonstrate the efficacy of the quantification technique two BNNT enrichment methods, surfactant wrapping and centrifugation, and a novel sonication-assisted isovolumetric filtration are introduced. FTIR spectra of enriched samples show clear trends throughout the processes. We propose and demonstrate that FTIR peak ratios of the transverse and buckling modes of mixed h-BN/BNNT samples can be used to calibrate and quantify h-BN content in any BNNT sample. Hopefully, this method enables as-received BNNTs to be quantifiably enriched from low purity commercial feedstocks, enabling future development and study of BNNTs and related technology.

In order to enhance the electrical energy storage capabilities of nanostructured carbon materials, inter-particle spacer strategies are needed to maintain ion-accessible surface area between the nanoparticles. This paper presents a comparison between different classes of divalent, dinuclear coordination complexes which both show strong adsorption to SWCNTs and have molecular spacer properties that maintain electrochemical activity. We find that a novel, dinuclear zinc hydrazone complex binds as an ion-pair at very high loading while not inducing significant aggregation as compared to our previously studies of dinuclear ruthenium complexes. These conclusions are supported by conductivity and dispersion stability data. Moreover, since zinc is an earth abundant metal, these complexes can be used as components in sustainable energy storage materials. Binding kinetics and binding equilibrium data are presented. Modeling of the adsorption isotherm is best fit with the BET model. Kinetics data support an independent binding model. Preliminary capacitance and membrane resistance data are consistent with the complexes acting as molecular spacers between the SWCNTs in a condensed thin film.

EP-001. CENTRAL NERVOUS SYSTEM TUMORS IN CHINESE CHILDREN UNDER THE AGE OF THREE: A POPULATION STUDY BY THE HONG KONG PAEDIATRIC HAEMATOLOGY/ ONCOLOGY STUDY GROUP Anthony Pak-Yin Liu1, Matthew Ming-Kong Shing2, Hui-Leung Yuen3, Chak-Ho Li4, Siu-Cheung Ling5, Chung-Wing Luk3, Shau-Yin Ha1, Chi-Kong Li2, and Godfrey Chi-Fung Chan1; Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong; Department of Paediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, Hong Kong; Department of Paediatrics, Queen Elizabeth Hospital, Hong Kong, Hong Kong; Department of Paediatics and Adolescent Medicine, Tuen Mun Hospital, Hong Kong, Hong Kong; Department of Paediatrics and Adolescent Medicine, Princess Margaret Hospital, Hong Kong, Hong Kong

The rational design of supraparticle assemblies requires a detailed understanding of directed assembly processes. The stability of dispersions of nanoscale materials, like single-walled carbon nanotubes (SWCNTs), is still not fully understood, nor are the mechanisms of aggregation and assembly. A detailed balance of attractive van der Waals type interactions with various repulsive barrier mechanisms is needed to control the assembly of industrially viable and functional hybrid-nanoscale supraparticles. We report a detailed study of SWCNT dispersion stability and aggregation kinetics as a function of the nature of the coagulant used in various solvent systems. We explore three classes of coagulants that vary in charge, size, shape, solvation energy, and the ability to bind to the SWCNTs. We use these kinetic data to assess the tube-solvent-coagulant-tube interactions. We compare the relative contributions from two types of repulsive barriers. We find that tube-mediated structured solvent around the SWCNTs does not sufficiently describe our measured kinetic data. A DLVO type, electrical double layer repulsion is used to rationalize our observations. The data presented in this paper require a more detailed theoretical understanding of the physico-chemical environment near nanoparticle surfaces such as aggregating SWCNTs.

The interaction enthalpy of amide solvents with single-walled carbon nanotube (SWCNT) dispersions is measured using isothermal titration calorimetry (ITC). N,N-Dimethyl-formamide (DMF) and N-methyl-2-pyrilidone (NMP) were used to make dispersions of highly purified (6,5) SWCNTs. Using isothermal titration calorimetry, the ΔH and K(A) terms related to the solvent-nanotube interactions were measured, and ΔG and ΔS of the interaction were determined. It was found that the interaction enthalpy of NMP with SWCNTs dispersed in DMF was exothermic. The addition of a second solvent into a NMP or DMF dispersion produced spontaneous exfoliation of SWCNT bundles as the solvent properties became more favorable. During the titration, a positive change in interaction entropy within the dispersed system due to the unbundling of SWCNTs was measured. From blank titrations of pure DMF into pure NMP and the reverse, dilution enthalpies were also calculated and compared to the literature, along with the corresponding enthalpic interaction coefficients, h(xx) and h(xxx). From our results, ITC appears to be a viable technique for measuring the interaction of solvent molecules with the surface of SWCNTs and for measuring the effect of mixed solvent properties on SWCNT dispersions.

Synthesis and characterization of the dinuclear ruthenium coordination complexes with heteroleptic ligand sets, [Cl(terpy)Ru(tpphz)Ru(terpy)Cl](PF6)2 (7) and [(phen)2Ru(tpphz)Ru(terpy)Cl](PF6)3 (8), are reported. Both structures contain a tetrapyrido[3,2-α:2′,3′-c:3′′,2′′-h:2′′,3′′-j]phenazine (tpphz) (6) ligand bridging the two metal centers. Complex 7 was obtained via ligand exchange between, RuCl2(terpy)DMSO (5) and a tpphz bridge. Complex 8 was obtained via ligand exchange between, [Ru(phen)2tpphz](PF6)2 (4) and RuCl2(terpy)DMSO (5). Metal-to-ligand-charge-transfer (MLCT) absorptions are sensitive to ligand set composition and are significantly red-shifted due to more electron donating ligands. Complexes 7–9 have been characterized by analytical, spectroscopic (IR, NMR, and UV–Vis), and mass spectrometric techniques. The electronic spectral properties of 7, 8, and [(phen)2Ru(tpphz)Ru(phen)2](PF6)4 (9), a previously reported +4 analog, are presented together. The different terminal ligands of 7, 8, and 9 shift the energy of the MLCT and the π–π* transition of the bridging ligand. These shifts in the spectra are discussed in the context of density functional theory (DFT). A model is proposed suggesting that low-lying orbitals of the bridging ligand accept electron density from the metal center which can facilitate electron transfer to nanoparticles like single walled carbon nanotubes and colloidal gold.

Myxoma virus (MV) encodes a cell surface protein (M135R) that is predicted to mimic the host alpha/beta interferon receptor (IFN-α/β-R) and thus prevent IFN-α/β from triggering a host antiviral response. This prediction is based on sequence similarity to B18R, the viral IFN-α/β-R from vaccinia virus (VV), which has been demonstrated to bind and inhibit type I interferons. However, M135R is only half the size of VV B18R. All other poxvirus-encoded IFN-α/β-R homologs align only to the amino-terminal half of M135R. Peptide antibodies raised against M135R were used for immunoblotting and immunofluorescence and indicate that M135R is expressed as an early gene and that the product is a cell surface N-linked glycoprotein that is not secreted. In contrast to the predicted properties of M135R as an inhibitor of type I interferon, all binding and inhibition assays designed to demonstrate whether M135R can interact with IFN-α/β have been negative. However, pathogenesis studies with a targeted M135-knockout MV construct (vMyx135KO) indicate that the deletion of M135R severely attenuates MV pathogenesis in the European rabbit. We propose that M135R is an important immunomodulatory virulence factor for myxomatosis but that the target immune ligand is not from the predicted type I interferon family and remains to be identified.

The Accreditation Council for Graduate Medical Education (ACGME) has defined 6 core competencies for all physicians: patient care; medical knowledge; practice-based learning and improvement; interpersonal and communication skills; professionalism; and systems-based practice. However, the specific wording of the descriptions often assumes that the physician is a clinician rather than a pathologist. Therefore, the American Association of Neuropathologists, Inc. asked its Professional Affairs Committee to examine the core competencies and determine how they relate to training in neuropathology. The Committee's report is presented here in 6 sections, corresponding to the 6 competencies. In each section, the ACGME definition of that particular competency is either quoted directly or, more often, modified slightly to clarify how the competency applies to neuropathology. Each of the defined competencies is then followed by possible assessment tools, selected from those recommended in the ACGME's "toolbox." Specific suggestions are given for designing tools that apply to neuropathology. Many of the suggested activities and documentation methods can be combined into efficient, carefully formulated training/evaluation exercises. Different tools may be more applicable in some training programs.

As a result of Johannesburg Stock Exchange regulations, the majority of equity issues are by rights issue. The objective of this study is to establish whether the South African market for rights issues is efficient. Using the Black-Scholes model, theoretical rights pricing boundaries were tested, and actual rights prices compared to model prices. Dilution adjusted and unadjusted model prices were calculated using historical standard deviation and implied standard deviation measures of volatility. Results showed inefficiencies associated with the lower boundary condition. The results for daily and per issue pricing indicate significant overpricing. Additional findings are that the dilution adjustment is required and the implied standard deviation is a better measure of volatility than the historical standard deviation.

We report the earliest in utero presentation of a 'giant' glioependymal cyst detected on routine prenatal ultrasound at 22 weeks estimated gestational age. The clinicopathologic features of these rare lesions are reviewed as well as previous reports of glioependymal cysts detected in utero. The effects of large intracranial cysts on neurodevelopment are discussed as well as the differential diagnosis of infantile intracranial cysts and therapeutic alternatives.

Summary. Removal trapping was used to try and reduce numbers of the predatory planarian Artioposthia triangulata in polythene tunnels on a nursery and a grass field. Ten months of trapping in the tunnels failed to have any impact upon flatworm numbers but weekly catches reduced over a period of 12 weeks' trapping in grassland. The calculated residual population in the grassland (40 ha-1) was small in comparison with that estimated from formalin sampling (940 × 1288 ha-1). A separate field study examined the effect of trap density on catch by spacing traps at 2.5, 5, 10 and 20 m intervals. This showed that the numbers of planarians caught was inversely related to the logarithm of trap spacing. It is concluded that removal trapping is too demanding of resources to be a viable control option for this pest in commercial and agricultural situations.

Supercapacitor devices promise to be an effective means of storing energy, and delivering power for personal electronics, remote sensors, and transportation.1, 2 Rare earth metals, such as ruthenium, have been used and report high value of capacitance, specific power, and energy.4 Nevertheless, the rarity of such metals prevent their practical use. In this study we utilize an earth-abundant nickel and a controlled microwave synthesis to create nickel oxide (NiO) with an optimal nanostructure for capacitance. To surpass the lofty series resistance associated with metal oxides such as NiO, we exploit the conductive properties of single and multi-walled carbon nanotubes. The carbon nanotubes and NiO can benefit from the presence of each other by preventing unnecessary aggregation.

A case of tumoral calcium pyrophosphate dihydrate crystal deposition disease involving the upper cervical spine is reported. It presented clinically, radiographically, and by preliminary intraoperative pathological evaluation as a possible malignant soft tissue tumor. An aggressive resection of the lesion was performed. This case differs from previous reports of calcium pyrophosphate dihydrate crystal deposition disease of the cervical spine by the size, location, and radiographic appearance of the lesion. We suggest that radical surgical procedures should not be performed without consideration of this diagnosis in lesions with similar presentations. A brief review of spinal and tumoral calcium pyrophosphate dihydrate crystal deposition is presented.

Discusses the problems and opportunities for researchers of access to electronic databases in an interview arising from a series of online “surgeries” at the British Library. Considers the problems of information overload and the effects of online provision in relation to traditional publishing. Also considers the economics for libraries, users and publishers of online research.

Integration of nanomaterials into composite systems is the next evolutionary step in nanoscale science. Until recently nanocomposites are formed by embedding nanomaterial components into matrices, through chemical bonding or with various wrapping agents. We seek to show that through directed self assembly nanomaterials can be coupled with photosensitizing ruthenium complexes while avoiding chemical augmentation and insulating effects from polymer, surfactant or DNA wrapping. We have synthesized dinuclear ruthenium complexes (dimers) possessing rigid conjugated π-electron systems that form a nanoscale pocket. The pocket is dimensionally suited to interact strongly with nanomaterials forming an architecture that could facilitate photon collection and charge transfer across the interaction. This study explores the binding interaction of our ruthenium dimers with SWNTs. The binding strength varies relative to the magnitude of formal charge which trends with DFT simulations that predict SWNT dimer interactions. SWNT surface saturation by ruthenium dimers can be observed using UV-visible spectroscopy and characterized with adsorption isotherms. We also explore a new technique to measure nanomaterial interactions, isothermal titration calorimetry (ITC). We show that ITC can be used to directly measure the binding enthalpy of nano material surface interactions in solution.

✓ The authors report the case of a hemangiopericytoma arising in a sciatic nerve. It was found to be invasive within the epineurium but sparing surrounding tissues. Adequate resection required sacrifice of the nerve. Hemangiopericytomas can be added to the short list of mesodermal peripheral-nerve tumors.

Toxic Trace Pollutant emission factors have been developed using a database of over 500 references, including 50 emission test reports for municipal solid waste (MSW) incineration. Procedures have been developed and computerized to calculate emission factors from the best available data for dioxin/furan toxic equivalents, carcinogenic PAHs, and other trace organics and metals. Statistical analyses have been performed on standardized test results to assess the relationship of emissions and various incineration and air pollution control equipment design and operating parameters. Although the data is much more limited for hazardous waste and medical waste incineration, the available data have been summarized.

Although neurologic changes after organ transplantation are often secondary to opportunistic infections or vascular insults, new pathological entities are emerging. We have recently encountered two patients who, a few days after liver and heart transplant, respectively, developed neurological signs and symptoms. Head computerized tomography (CT) scan showed nonenhancing areas of low attenuation, and magnetic resonance imaging (MRI) demonstrated multiple areas of increased signal intensity in the subcortical white matter on T2-weighted images. Stereotactic biopsy of the intracranial lesions was performed in one case. Light microscopic examination demonstrated only mildly edematous white matter. No infectious organisms were observed on light or electron microscopy. In one patient, follow-up MRI 3 months later showed almost complete resolution of the signal abnormalities. Both patients' clinical condition progressively improved. The neuroradiological abnormalities described are consistent with the 'reversible posterior leukoencephalopathy' syndrome associated with cyclosporine toxicity. The pathophysiology of these lesions is unclear; however, it has been suggested that cyclosporine causes an acute ischemic insult secondary to vascular spasm with resultant axonal swelling. This hypothesis is supported by the hypoattenuation seen on CT, the prolonged T2 relaxation seen on MRI, and the absence of contrast enhancement. Concomitant factors (such as hypocholesterolemia or associated therapy with high dose steroids) are important in the development of these lesions as in both of our patients cyclosporine levels were in the normal range. Fortunately, these lesions and the associated manifestations are most often reversible and regress with adjustments of cyclosporine dosage and/or correction of concomitant facilitating factors.

We report a case of primary solitary fibrous tumor occurring in the intramedullary thoracic spinal cord in a 47-year-old man. The tumor predominately consisted of spindle cells separated by abundant collagen; a few areas of hemangiopericytomatous morphology were also present. The diagnosis was confirmed by immunohistochemistry and electron microscopy. The tumor was reactive to vimentin and CD34 but was negative for glial fibrillary acid protein (GFAP), S-100, smooth muscle actin, epithelial membrane antigen, HMB-45, myelin basic protein, and keratin; ultrastructural examination showed fairly undifferentiated cells within a collagenous matrix, few tight junctions, and sparse extravascular basement membrane. The occurrence of this tumor within the spinal cord parenchyma and in other extraserosal sites emphasizes the current belief that solitary fibrous tumors arise from mesenchymal tissues and are not restricted to the pleura and other serosal surfaces. Furthermore, solitary fibrous tumor is an entity that must be considered in the differential diagnosis of spindle cell central nervous system neoplasms.

We report the earliest in utero presentation of a 'giant' glioependymal cyst detected on routine prenatal ultrasound at 22 weeks estimated gestational age. The clinicopathologic features of these rare lesions are reviewed as well as previous reports of glioependymal cysts detected in utero. The effects of large intracranial cysts on neurodevelopment are discussed as well as the differential diagnosis of infantile intracranial cysts and therapeutic alternatives.