Mossbauer spectroscopy was used to study the valence and bonding changes of iron in (a) lattice sites, and (b) cation exchange sites during thermal treatment of kaolinite and halloysite. Lattice iron which is initially in octahedral sites occurs in octahedral and tetrahedral sites at the completion of the thermal reactions. At temperatures below 650°C some divalent ions in cation exchange positions become trivalent and assume octahedral co-ordination, which they retain until the later stages of mullite formation. The implications of the work on the high temperature reaction mechanism and structural sequence are discussed.

A green smectitic mineral from Jordan with 16% Cr2O3 (almost 22% on an ignited basis) has been shown by chemical, X-ray, electronoptical, electron microprobe, infrared and thermoanalytical evidence to be an iron-free volkonskoite of composition:

The octahedral occupancy of 4·7, with only Mg2+ and Cr3+ in octahedral positions (in a ratio of 1·14), suggests that the mineral is intermediate between di- and trioctahedral—an inference supported by the uniformity of composition of individual particles (as revealed by the microprobe) and IR evidence, which indicates that it is predominantly dioctahedral but with certain trioctahedral characteristics. A volkonskoite sample from the type area in the USSR, examined for comparison, contained 23·5% Cr2O3 (about 29% on an ignited basis), but proved on electron microprobe examination to be a mixture of at least three species, one of which was aluminium-rich. IR and thermoanalytical characteristics are discussed in relation to the existence of tri-dioctahedral species.

The cause of coloration of Blue John fluorite from Castleton, Derbyshire, and blue banded fluorites from Ashover, Derbyshire, and Weardale, Co. Durham, has been investigated by a number of techniques, including mass spectrometry, optical spectroscopy, and paramagnetic resonance measurements on natural and irradiated samples. In all respects Blue John is indistinguishable from the other blue banded fluorites. Although traces of hydrocarbons were found in all the natural fluorites including Blue John, they are shown not to be the cause of the colouration. The optical spectra and bleaching behaviour are consistent with colouration by colloidal calcium rather than F-centres. The causes of colour banding are discussed.

The mechanisms by which coatings develop on weathered grain surfaces, and their potential impact on rates of fluid-mineral interaction, have been investigated by examining feldspars from a 1.1 ky old soil in the Glen Feshie chronosequence, Scottish highlands. Using the focused ion beam technique, electron-transparent foils for characterization by transmission electron microscopy were cut from selected parts of grain surfaces. Some parts were bare whereas others had accumulations, a few micrometres thick, of weathering products, often mixed with mineral and microbial debris. Feldspar exposed at bare grain surfaces is crystalline throughout and so there is no evidence for the presence of the amorphous ‘leached layers’ that typically form in acid-dissolution experiments and have been described from some natural weathering contexts. The weathering products comprise sub-urn thick crystallites of an Fe-K aluminosilicate, probably smectite, that have grown within an amorphous and probably organic-rich matrix. There is also evidence for crystallization of clays having been mediated by fungal hyphae. Coatings formed within Glen Feshie soils after ∼1.1 ky are insufficiently continuous or impermeable to slow rates of fluid-feldspar reactions, but provide valuable insights into the complex weathering microenvironments on debris and microbe-covered mineral surfaces.

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) represent a disease continuum with common genetic causes and molecular pathology. We recently identified mutations in the T-cell restricted intracellular antigen-1 (TIA1) protein as a cause of ALS +/− FTD. TIA1 is an RNA-binding protein containing a low complexity domain (LCD) that promotes the assembly of membrane-less organelles, such as stress granules (SG). Whole exome sequencing of two family members with fALS/FTD revealed a novel missense mutation in the TIA1 LCD (P362L). Subsequent screening identified five more TIA1 mutations in six additional ALS patients, but none in controls. All mutation carriers presented with weakness, behavioral abnormalities or language impairments and had a final diagnosis of ALS +/− FTD. Autopsy on five TIA1 mutation carriers showed widespread neurodegeneration with TDP-43 pathology. Round eosinophilic inclusions in lower motor neurons were a consistent feature. Cellular assays revealed abnormal SG dynamics in the presence of TIA1 mutations. In summary, missense mutations in the LCD of TIA1 are a newly recognized cause of ALS/FTD with TDP-43 pathology and strengthen the role of RNA metabolism in the pathogenesis in this disease.

Introduction: Aeromedical helicopters and fixed wing aircraft are used across Canada to transfer patients to definitive care. Given height limitation in aeromedical transport, CPR performance can be affected. An adapted manual compression technique has been proposed by H. Koch (pron. Cook) that uses the elbow to compress the sternum rather than the conventional hand. This preliminary study evaluated the quality of Koch compressions versus conventional bimanual compressions. Methods: Paramedics (5), registered nurses (3) and a physician (1) were recruited. Each participant performed a 2 minute cycle of each technique, were randomized to determine which technique was performed first, and rested 5 minutes between compression cycles. A Resusci Anne SkillReporter manikin atop a stretcher in a BK117 helicopter was used. The compressors performed without feedback or prompting. Outcomes include compression rate, depth, recoil, and fatigue. Results: The mean conventional compression rate was (bpm) 118 +/− 13 versus 111 +/− 10 in the Koch scenario (p=0.02) (target 100 to 120). Mean conventional compression depth (mm) was 44 +/− 9 versus 49 +/− 7 in the Koch scenario (p=0.01) (target 50 to 60). The mean percentage of compressions with complete release in the conventional scenario was 86 +/− 20 versus 84 +/− 22 in the Koch scenario (p=0.9) (target 100%). Using a Modified Borg Scale of 1 to 10, mean provider fatigue after conventional CPR was 7 (+/− 1.6) versus 3 (+/− 1.2) using Koch technique (p<0.001). On average, Koch technique improved the percentage of compressions at target rate by 26%, the percentage at correct depth by 9%, overall compression quality score by 13% and were more less fatiguing. Conclusion: Using an elbow in a height-restricted environment improved compression depth and reduced provider fatigue. From our limited data, Koch compressions appear to improve compression quality. Further study and external validation are required.

This short-term, open-label study investigates short- and long-term effects of the selective serotonin reuptake inhibitor (SSRI) fluvoxamine for the treatment of trichotillomania (TTM). Additionally, this study aimed to test the hypothesis that the presence of hair pulling compulsiveness is predictive of SSRI response. Nineteen subjects meeting the Diagnostic and Statistical Manual of Mental Disorders, Third Edition Revised, (DSM-III-R) criteria for TTM were treated with fluvoxamine at doses up to 300 mg/day. Random regression analysis of change across time for patients who completed the study (n=14) and those who dropped out (n=5) revealed statistically significant improvements in Physician Rating Scale, hair-pulling episodes, Trichotillomania Impairment Scale, and Trichotillomania Symptom Severity Scale, but not in estimated amount of hair pulled. In addition, the percentage of patients' focused or compulsive hair-pulling symptoms was predictive of treatment response. Unfortunately, all three subjects who entered long-term treatment displayed substantial movement back toward baseline by the end of 6 months. We concluded that fluvoxamine produces moderate reductions in symptoms during the short-term treatment of TTM and that the presence of focused or compulsive hair pulling may be predictive of treatment response. However, responses may be short lived when treatment is extended.

A series of synthetic calcium silicates has been produced comprising nano-sized plates. The starting calcium silicate referred to as nano-structured calcium silicate, NCS, appears itself X-ray amorphous but contains impurities of calcite. These impurities decompose during the dry thermal conversion of the material into wollastonite. NCS can be enriched with calcium or silicon, respectively. The silicon enriched NCS can be hydrothermally transformed into a sheet material related to Ca7Si16O38(OH)2. The X-ray pattern of this material was sufficient to allow the calculation of its unit cell with a comparatively high figure of merit. The calcium enriched NCS can form two very distinctly different ceramic materials upon hydrothermal treatment, one a band material (formed below 200 °C) and the other a rose petal shaped material (formed above 210 °C). The X-ray diffraction patterns could not be resolved. The fit between the observed and calculated patterns was less than 50% as expressed in comparatively low figures of merit (unusually <20), which is attributed to calcium carbonate impurities in the samples disrupting the long range order. The patterns of these calcium enriched samples could be best compared to those of tobermorite or truscotite.

The patients we are concerned about in tropical medicine are unfortunately affected by a wide range of conditions, not only those seen and studied extensively in the West, such as cancer, cardiovascular diseases and viral or bacterial infections, but also the major protozoan and metazoan conditions – the parasitic diseases. It is with this spectrum of pathophysiological changes that occurs in this last group that we are presently concerned and this communication is intended to present an overview of the subject.

Some philosophers suspect that the functionalist account of mind supports a psychologistic account of logic. One who has argued for a connection of this kind is Remmel T. Nunn. If the connection holds, it might be a powerful support for the currently unfashionable position of psychologism; conversely, it might be a damaging objection to functionalism. In either case, to estabjish the connection would be an achievement of considerable philosophic interest.