The thermal reaction sequence of a synthetic hectorite (Laponite CP) was studied by X-ray diffraction, i.r. spectroscopy and thermal analysis. Although most of the interlayer water is removed at 200°C, a smally steady weight loss occurs until dehydroxylation is complete at about 700°C, indicating that an anhydrous intermediate phase is not formed prior to dehydroxylation. Immediately after dehydroxylation, enstatite and cristobalite can be identified, but lithium silicates are formed only from lithium-saturated hectorite. Around 1200°C a glass is formed by reaction of the alkalis with cristobalite, and removal of silica from the enstatite produces some forsterite. An inhomogeneous mechanism of dehydroxylation is postulated by analogy with that proposed for talc.

Solid-state nuclear magnetic resonance (NMR) spectroscopy, thermal analysis, and X-ray powder diffraction data on the tubular, hydrous aluminosilicate imogolite were found to be fully consistent with a previously proposed crystal structure consisting of a rolled-up, 6-coordinate Al-O(OH) sheet, bonded to isolated orthosilicate groups. The calculated 29Si chemical shift of this structure agreed with the observed shift within 3 ppm. Thermal dehydroxylation of the Al-O(OH) sheet produced predominantly NMR-transparent 5-coordinate Al, but a few 4- and 6-coordinate sites and some residual hydroxyl groups may also have formed, as shown by NMR spectroscopy. Changes in the 29Si NMR spectrum on dehydroxylation suggest a condensation of the orthosilicate groups, but steric considerations rule out bonding between adjacent silicons. To account for these observations, an alternative mechanism to orthosilicate condensation has been proposed, involving the fracture and unrolling of the tubes, followed by the condensation of fragments to form a layer structure. The layer structure has a calculated 29Si chemical shift of -95.6 ppm, in good agreement with the observed value of -93 ppm.

Examination of two volcanic and two precipitated allophanes by solid-state NMR, thermal analysis and X-ray powder diffraction shows three of the samples to contain structural features similar to both tubular imogolite and defect layer-lattice aluminosilicates such as kaolinite. The fourth allophane, a precipitated sample from New Zealand, had no imogolite-like features and contained tetrahedral as well as octahedral aluminum. The imogolite-like units in allophane are less stable thermally than tubular imogolite. The NMR spectra and their changes on heating can be accounted for by a structural model in which a two-sheet, kaolinite-like structure containing defects (holes in the tetrahedral sheet) is curved into a sphere in which imogolite-like orthosilicate units are anchored into the octahedral sheet and fit into the tetrahedral defects. Computer simulation shows that the model is crystallographically sound, and accounts for all the known facts, including the spherical morphology, the solid-state NMR spectra and the thermal dehydroxylation behavior of all except the New Zealand allophane, which is of a different structural type.

A G4C2 repeat extension in the first intron of C9ORF72 is the most common cause of familial frontotemporal dementia with and without motoneuron disease or atypical Parkinsonism. We recently found that the characteristic p62 positive/TDP43 negative neuronal cytoplasmic inclusions (NCIs) mainly seen in cerebellum und hippocampus consist of different dipeptide repeat proteins (DPRs) generated by an ATG independent translation of stable sense and antisense transcripts of the extended intron.

After creating specific antibodies against all potential DPRs resulting from different reading frames, we investigated their regional and cellular distribution pattern in the central nervous system of autopsy cases with C9ORF72 mutation by immunohistochemistry.

Aggregates of all DPRs were seen in neuronal cell bodies and processes. Glycine-alanine and glycine-prolin DPRs dominated. NCIs were abundant in all neocortical areas, in the hippocampal formation and in cerebellum, less frequent in subcortical nuclei, and rare in brain stem and spinal cord following a rostro-caudal gradient. Different DPRs were found in the same NCI. The regional distribution pattern of NCIs was similar in all clinical subtypes, and did not directly correlate with neurodegeneration. DPRs and TDP43 that usually also aggregates in C9ORF72 mutation cases were rarely co-localized in the same NCI. In case of co-localization DPR proteins formed a central core surrounded by TDP43.

The detection of DPR inclusions directly connects the mutation with specific neuropathological alterations. The formation of DPR inclusions seems to precede the formation of TDP43 inclusions. If there is a neurotoxic effect of DPRs, DPR inclusions might be neuroprotective.

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.

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.

Introduction: It is critical for planning, clinical care and resource optimization to understand patterns of emergency department (ED) utilization. Individuals who have experienced adverse childhood experiences (ACE) are known to have more unhealthy behaviors and worse health outcomes as adults and therefore may be more frequent ED users. Adverse childhood experiences include physical, sexual and emotional abuse or neglect, substance abuse in the family, witnessing violence, having a parent incarcerated or parents getting divorced or separated. To date there are few studies exploring the relationship between ACE and ED utilization. Methods: This a mixed qualitative and quantitative study. It includes analysis of data collected through a survey, a retrospective chart review and focus group discussions. The survey was administered to a convenience sample of adult patients (CTAS 2 -5) presenting to EDs in Kingston Ontario, and consisted of two validated tools that measured exposure to ACE and resiliency. Demographic data and ED utilization frequency for 12 months prior to the index visit were extracted from an electronic medical record for each patient completing the survey. A sample of participants with a high ACE burden (ACE score > 4) were invited to participate in focus groups to explore their experiences of care in the ED. Demographic, ED utilization and health status data were summarized and statistically significant patterns between high ACE and lower ACE patients were determined using Chi2t or t-tests. Transcripts from the focus groups were thematically analyzed using NVivo software by 2 independent researchers. Results: 1693 surveys were collected, 301 (18%) were deemed to have a high ACE score, data analysis is ongoing. The primary outcome is the relationship between ACE and the frequency of ED utilization among adult patients presenting to EDs in Kingston, ON. Secondary outcomes include evaluating the role of resilience as a potential mitigating factor, describing the demographics of high ACE burden frequent ED visitors, and the experiences of care for individuals with high ACE burden in the ED. These outcomes will be utilized to inform hypotheses for future studies and potential interventions aimed at optimizing ED utilization and patient care experience. Conclusion: This study provides novel insight into the relationship between ACE burden and ED utilization while also describing the demographics and experiences of care for ED patients with a high ACE score. Data analysis is on-going.

A series of investigations was conducted to evaluate the comparative attractiveness of cattle, sheep and goats to Glossina morsitans morsitans Westw. and G. pallidipes Aust. in the Zambesi Valley, Rhodesia. It was shown that cattle are subjected to in excess of three times the challenge by male G. m. morsitans than either sheep or goats. Due to the repellent effect of man's presence on the attraction and feeding of female G. m. morsitansand both male and female G. pallidipes on the bait animals, no rational relationship could be postulated for them. Possible factors accounting for the difference of attractiveness between the three bait species are discussed.

The comparative attractiveness to Glossina morsitans morsitans Westw. and G. pallidipes Aust. of donkeys, cattle, sheep and goats in the presence of wild game was examined during two investigations in a middle-veld area of Rhodesia. Host preferences were assessed by the identification of blood-meals collected in the grazing area. Both cattle and donkeys provided a high proportion of the diet. Sheep and particularly goats were fed upon to a minor degree. The significance of the findings is discussed in relation to tsetse control.

Healthy multiparous women having elective interval (N = 69) or postpartum (N = 69) sterilization were interviewed pre-operatively and 6 weeks and 6 months post-operatively, using standardized instruments. They did not differ significantly from control samples of comparable non-sterilized women with respect to mental state (Present State Examination) or subjectively-assessed mental or physical health or abdominal pain. More sterilization subjects than control subjects reported subjectively experienced improvement in sexual satisfaction at the later follow-up. Reports of poor physical health and abdominal pain increased over time within both the sterilization and the control groups. Reports of adverse effects at follow-up were often associated with higher PSE scores initially. Regrets and wish for reversal were rare and were also associated with higher initial PSE scores. Since the adverse effects were more common among postpartum subjects, it is suggested that subjectively experienced sequelae of sterilization may sometimes be attributable to ‘normal’ postnatal events.

The small subunit ribosomal RNA (srRNA) gene was amplified from Gyrodactylus salaris using the polymerase chain reaction (PCR), cloned, and the complete gene sequence of 1966 bp determined. The V4 region of the srRNA gene was identified and amplified from single specimens of G. salaris, G. derjavini and G. truttae. Comparison of the V4 sequences from these three species revealed sequence differences from which restriction fragment length polymorphisms (RFLPs) were predicted and an oligonucleotide probe (GsV4) specific to G. salaris designed. Digestion of the amplified V4 region of the srRNA gene with Hae III and either Alw I, BstY I, Dde I or Mbo I provided a means of discriminating between G. salaris, G. derjavini and G. truttae. The GsV4 probe was used to detect the srRNA gene from G. salaris in Southern and dot blots of the amplified V4 region. The nucleotide sequences reported in this paper have been submitted to the EMBL Data Library under accession numbers Z26942 (G. salaris), Z35128 (G. derjavini) and Z35129 (G. truttae).

As part of a prospective controlled study of the psychosomatic effects of elective tubal sterilization, 138 women were questioned about their menstrual functioning before sterilization, and again 6 months and 12 months post-operatively, using standardized interviewing procedures. Adverse changes, including (subjectively assessed) increased menstrual loss, shorter menstrual cycles and greater use of pads or tampons were reported by sterilized subjects at both of the post-operative interviews. Control subjects reported several comparable effects, although adverse changes overall were reported more commonly by sterilized women than by control subjects. However, many of the reported changes appeared to be related to pre-operative contraceptive methods, although consistent increases in use of pads or tampons were found in women who had pre-operatively used neither the pill nor the IUD.

High-density plasma technology is becoming increasingly attractive for the deposition of dielectric films such as silicon nitride and silicon dioxide. In particular, inductively-coupled plasma chemical vapor deposition (ICPCVD) offers a great advantage for low temperature processing over plasma-enhanced chemical vapor deposition (PECVD) for a range of devices including compound semiconductors. In this paper, the development of low temperature (< 200°C) silicon nitride and silicon dioxide films utilizing ICP technology will be discussed. The material properties of these films have been investigated as a function of ICP source power, rf chuck power, chamber pressure, gas chemistry, and temperature. The ICPCVD films will be compared to PECVD films in terms of wet etch rate, stress, and other film characteristics. Two different gas chemistries, SiH4/N2/Ar and SiH4/NH3/He, were explored for the deposition of ICPCVD silicon nitride. The ICPCVD silicon dioxide films were prepared from SiH4/O2/Ar. The wet etch rates of both silicon nitride and silicon dioxide films are significantly lower than films prepared by conventional PECVD. This implies that ICPCVD films prepared at these low temperatures are of higher quality. The advanced ICPCVD technology can also be used for efficient void-free filling of high aspect ratio (3:1) sub-micron trenches.