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Necrotizing enterocolitis (NEC) is a devastating gastrointestinal illness that affects high-risk populations such as those with congenital heart disease (CHD). A diagnosis of NEC, before and after cardiac surgery, can have serious and irreversible consequences. Here, we review perioperative management strategies that could potentially reduce the incidence of NEC in CHD. The literature is rich in investigative work regarding NEC in preterm infants; however, these data are extrapolated to infants with CHD. The pathogenesis of NEC in CHD is thought to be multifactorial, with splanchnic hypoperfusion being a major contributor. The data suggest that early enteral feeding with human milk, the use of probiotics, thoughtful use of red blood cell transfusions, and near-infrared spectroscopy may be useful tools in the prevention of NEC. NEC is an illness with the potential for high morbidity and mortality, particularly in CHD. Therefore, prevention of NEC should be the clinician’s focus when caring for these infants. Well-designed studies and evidence-based guidelines to standardize care in these infants are much needed to improve the outcome of NEC.

A novel spherical convolution is defined through the sifting property of the Dirac delta on the sphere. The so-called sifting convolution is defined by the inner product of one function with a translated version of another, but with the adoption of an alternative translation operator on the sphere. This translation operator follows by analogy with the Euclidean translation when viewed in harmonic space. The sifting convolution satisfies a variety of desirable properties that are lacking in alternate definitions, namely: it supports directional kernels; it has an output which remains on the sphere; and is efficient to compute. An illustration of the sifting convolution on a topographic map of the Earth demonstrates that it supports directional kernels to perform anisotropic filtering, while its output remains on the sphere., 5 pages, 3 figures

Wavelets are widely used in various disciplines to analyse signals both in space and scale. Whilst many fields measure data on manifolds (i.e., the sphere), often data are only observed on a partial region of the manifold. Wavelets are a typical approach to data of this form, but the wavelet coefficients that overlap with the boundary become contaminated and must be removed for accurate analysis. Another approach is to estimate the region of missing data and to use existing whole-manifold methods for analysis. However, both approaches introduce uncertainty into any analysis. Slepian wavelets enable one to work directly with only the data present, thus avoiding the problems discussed above. Applications of Slepian wavelets to areas of research measuring data on the partial sphere include gravitational/magnetic fields in geodesy, ground-based measurements in astronomy, measurements of whole-planet properties in planetary science, geomagnetism of the Earth, and cosmic microwave background analyses., Comment: 4 pages

OBJECTIVES/HYPOTHESIS Infants who undergo congenital heart surgery are at risk of developing vocal fold motion impairment (VFMI) and swallowing difficulties. This study aims to describe the dysphagia in this population and explore the associations between surgical complexity and vocal fold mobility with dysphagia and airway protection. STUDY DESIGN Retrospective chart review. METHODS This is a retrospective chart review of infants (age

This work presents the construction of a novel spherical wavelet basis designed for incomplete spherical datasets, i.e. datasets which are missing in a particular region of the sphere. The eigenfunctions of the Slepian spatial-spectral concentration problem (the Slepian functions) are a set of orthogonal basis functions which are more concentrated within a defined region. Slepian functions allow one to compute a convolution on the incomplete sphere by leveraging the recently proposed sifting convolution and extending it to any set of basis functions. Through a tiling of the Slepian harmonic line, one may construct scale-discretised wavelets. An illustration is presented based on an example region on the sphere defined by the topographic map of the Earth. The Slepian wavelets and corresponding wavelet coefficients are constructed from this region and are used in a straightforward denoising example., 12 pages, 14 figures

OBJECTIVES: The role of the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in the assessment of disease activity in systemic sclerosis (SSc) remains controversial. We sought to evaluate the relationship between clinical features of SSc and raised inflammatory markers and to determine if changes in ESR and CRP reflect changes in other disease features over time. METHODS: One thousand, five hundred and forty-five patients enrolled in the Australian Scleroderma Cohort Study were observed over a mean 3.52±2.91 years and assessed at 6,119 study visits. Generalised estimating equations were used to determine the relationship between ESR≥20mm/hr and CRP≥5mg/L and features of disease. The associations between change in inflammatory markers and change in skin scores and respiratory function tests were analysed. RESULTS: Overall, there was a significant association between raised ESR and forced vital capacity (FVC)

The advent and improvement of laparoscopic surgical techniques have led to expanded surgical and diagnostic indications for this technology in the pediatric patient. The anesthetic management in these cases poses special challenges due to pneumoperitoneum and extreme patient positioning (Nezhat et al., Nezhat’s video-assisted and robotic-assisted laparoscopy and hysteroscopy. Cambridge University Press, New York, 2013; Tanaka et al., Nezhat’s video-assisted and robotic-assisted laparoscopy and hysteroscopy. Cambridge University Press, New York, 2013). This chapter takes a close look at anesthetic challenges of pediatric and adolescent patients scheduled for laparoscopic surgery. It also describes preoperative considerations for pediatric surgery patients, including patient screening and premedication. Specific intraoperative and postoperative issues, including perioperative complications, pain management, and postoperative nausea and vomiting, all which are important for providing quality care and efficient patient experience, are discussed. The knowledge of the patient’s health status, along with the multiple physiologic changes that can occur and specific potential complications, allows the anesthesiologist to provide safer anesthesia care. This chapter provides an evidence-based overview of particular strategies in anesthesia care that have been utilized to improve the experience for pediatric and adolescent patients and their families.

Background and aims Postoperative pain relief management remains challenging post Caesarean section. the QLB has been shown to provide satisfactory analgesia post Caesarean section under neuraxial anaesthesia. However, its utility has not been demonstrated in patients who have received spinal morphine. the aim of this study is to assess the efficacy of the QLB as part of a multi modal analgesic regimen including spinal morphine post Caesarean section. Methods We performed a prospective, double-blind, placebo-controlled trial of 90 patients undergoing elective Caesarean section under spinal anaesthesia. Parturients were randomly allocated to receive a bilateral QLB or a sham block at the end of their surgery. the primary outcome was the difference in morphine PCA consumption over 24 hours after Caesarean section. Results There was no significant difference in morphine PCA consumption at 24 hours between the QLB group and control group (p = 0.986). There was a statistically significant reduction in VAS (Visual Analogue Scale) pain scores at 6 hours both at rest and at movement (p = 0.019, p = 0.014 respectively). There was no significant difference in VAS pain scores at any other timepoint up to 48 hours. Conclusions The QLB did not reduce morphine consumption at 24 hours but there was a reduction in VAS at 6 hours at rest and on movement. Increasing the local anaesthetic concentration and the addition of adjuncts could improve its analgesic profile when used in conjunction with spinal morphine.

Quadratus lumborum block has been shown to provide satisfactory analgesia after caesarean section performed under neuraxial anaesthesia. However, its efficacy has not been demonstrated in patients who have received intrathecal morphine. The aim of this study was to assess the efficacy of quadratus lumborum block as part of a multimodal analgesic regimen including intrathecal morphine. This was a prospective, double-blind, placebo-controlled trial. Participants were randomly allocated to receive bilateral quadratus lumborum block (40 ml levobupivacaine 0.25%) or sham block (control) after undergoing elective caesarean section under spinal anaesthesia. The primary outcome was 24-h morphine consumption measured by patient-controlled analgesia. Secondary outcomes included pain scores and quality of recovery. Data from 86 women were analysed. Median (IQR [range]) 24-h morphine consumption was similar in patients receiving quadratus lumborum block and sham block (12 (8-29 [0-68]) mg vs. 14 (5-25 [0-90]) mg, respectively; p = 0.986). There was a reduction in median (IQR [range]) visual analogue scale pain scores at 6 h with quadratus lumborum block compared with sham block both at rest (6 (0-14 [0-98]) mm vs. 14 (3-23 [0-64]) mm (p = 0.019); and on movement: 23 (10-51 [0-99]) mm vs. 44 (27-61 [2-94]) mm; (p = 0.014)). There was no difference in pain scores at any other time-point up to 48 h. When used in conjunction with intrathecal morphine and spinal anaesthesia, bilateral quadratus lumborum block does not reduce 24-h morphine consumption after caesarean section.

Introduction. Understanding the genetic architecture of scleroderma (SSc) susceptibility is vital both in gene discovery and in determining the influence of previously identified susceptibility variants. It is particularly important in understanding disease mechanism in a disease with few therapies and great morbidity and mortality. Methods. We selected 557 cases from the Australian Scleroderma Cohort Study (ASCS), for genotyping with the Immunochip, a custom Illumina Infinium genotyping array containing 196 524 rare and common variants shown to be important in a wide variety of autoimmune disorders. A total of 4537 controls were taken from the 1958 British Birth cohort. Genotype data were analysed with PLINK. Samples and SNPs with low call rates were excluded, as were SNPs in Hardy-Weinberg disequilibrium or with less than two occurrences of the minor allele. Eigenstrat was used to analyse population structure. The final data set consisted of 505 cases, 4491 controls and 146 867 SNPs. Allelic association analyses were conducted using Fisher's exact test. Genotype clusters were manually examined for all associations of P < 10−5 since calling is difficult for some rare variants. Results. Significant and suggestive associations were detected at seven loci. Several of these have been previously implicated in scleroderma susceptibility (HLA-DRB1 and STAT4) and several are novel associations, including SNPs near PXK (P = 4.4 × 10−6) and CFDP1(P = 2.6 × 10−6). The strongest associations were with SNPs in the Class II region of the MHC. One of the most strongly associated SNPs [rs4639334; P = 1.6 × 10−8; odds ratio (OR) = 1.8] is in linkage disequilibrium (r2 = 0.46) with the Class II allele HLA-DRB1*11:01. This allele has been associated with SSc. Another strongly associated SNP is rs2857130 (P = 1.6 × 10−8; OR = 0.67), which lies in the promoter region of HLA-DRB1, but is not in LD with any classical MHC alleles. Outside the MHC, there were six regions of association with P < 10−5,including the confirmed SSc locus at STAT4. Several SNPs implicate a locus at PXK, which has been previously associated with SLE but not with SSc. The remaining associations are novel for both SSc and SLE and require replication. Of particular interest is a rare variant located within a non-coding RNA on chromosome 6q21 which was ∼20 times more frequent in cases than controls. We are currently dissecting the potential biological implications of this locus. Conclusions. This pilot study has confirmed previously reported SSc associations, revealed further genetic overlap between SSc and SLE, and identified putative novel SSc susceptibility loci including a rare allele with major effect size

Objective To evaluate the hypothesis that feeding volumes exceeding 100 mL/kg/d and exposure to cow's milk formula preoperatively increase the risk for preoperative necrotizing enterocolitis (NEC) in infants with complex congenital heart disease. Study design All infants, of any gestational age, with an isolated cardiac lesion at high risk for NEC (ductal-dependent lesions, transposition of the great arteries, truncus arteriosus, and aorto-pulmonary window) admitted to Texas Children's Hospital from 2010 to 2016 were included. NEC was defined based on the modified Bell criteria. Feeding regimen information and relevant covariates were collected. Logistic regression was used to evaluate the association of feeding regimen and other potential risk factors with NEC. Results In this single-center, retrospective cohort of 546 infants, 3.3% developed Bell stage I-III NEC preoperatively. An exclusive unfortified human milk diet was associated with a significantly lower risk of preoperative NEC (OR 0.17, 95% CI 0.04-0.84, P = .03) in a multivariable regression model controlling for cardiac lesion, race, feeding volume, birth weight small for gestational age, inotrope use presurgery/pre-NEC, and prematurity. Feeding volumes exceeding 100 mL/kg/d were associated with a significantly greater risk of preoperative NEC (OR 3.05, 95% CI 1.19-7.90, P = .02). Conclusions The findings suggest that an unfortified exclusive human milk diet may reduce the risk of preoperative NEC in infants with complex congenital heart disease.

Background Crawford Williamson Long (1815 to 1878) was the first to use ether as an inhaled anesthetic for surgical operations. By not publishing his discovery for 7 yr, his pioneering work was largely overshadowed by that of Horace Wells (1815 to 1848), Charles Thomas Jackson (1805 to 1880), and William Thomas Green Morton (1819 to 1868). As a result, sites commemorating Long’s discovery are not offered the same recognition as those affiliated with Wells or Morton. Methods We highlight sites in Athens, Danielsville, and Jefferson, Georgia, that honor the first man to regularly use ether as an anesthetic agent. Extensive site visits, examination of museum artifacts, and genealogical research were used to obtain information being presented. Results Historic Oconee Hill Cemetery in Athens is where Long and members of his family are buried. Established in 1856, it is closely linked to the history of Athens and the University of Georgia (Athens, Georgia). The main site we describe is the Crawford W. Long Museum, located in Jefferson, Georgia, which opened to the public in 1957. It has undergone extensive renovations and holds an expansive collection of Long’s family heirlooms and personal artifacts. In addition, it displays an impressive art collection, depicting Long, surgical procedures, members of Long’s family, and homes associated with him. Visitors to the museum may also enjoy a walking audio tour that highlights the life of Long and his contribution to medicine. Conclusions We provide information on sites and artifacts that honor Georgia’s most celebrated physician. Much of this has not been published before, and it is our hope that Crawford Williamson Long’s legacy receives the attention it richly deserves.

This paper reports on work carried out as part of a joint UK–China study to identify the best way of harnessing the natural resources of Chongming County’s three islands in order to meet future energy demands in a cost-effective manner with minimum reliance on fossil fuels, consistent with the concept of a prestigious ecological island. Across the three Chongming islands, there are seven distinct zones, each with different functions, living styles and energy demand patterns – and thus different opportunities for deployment of renewable energy resources. Various biomass resources (from farming, forestry, municipal waste, and so on) and conversion technologies (e.g. gasification, anaerobic digestion) are evaluated and considered alongside wind, solar, tidal and geothermal options. Distributed energy features prominently in the proposed solution as this allows the most efficient use of both electricity and heat, as well as being suited to many renewable energy resources, which are naturally highly distributed. Compared with a conventional approach, the proposed solution offers carbon dioxide savings of 30%.

Video laryngoscopy facilitates tracheal intubation during manual in-line stabilization in adults, but it is not clear whether these findings translate to children. We compared trainee intubation times obtained using the GlideScope Cobalt® and Storz DCI® video laryngoscopes versus direct laryngoscopy in young children with immobilized cervical spines.Ninety-three children younger than 2 years underwent laryngoscopy with manual in-line stabilization using direct laryngoscopy, GlideScope Cobalt® video laryngoscopy, or Storz DCI® video laryngoscopy. Laryngoscopists were anesthesiology trainees in postgraduate training year of 3 or more. Total time to successful intubation (TTSI), best glottic view, and maximum degrees of neck deviation were recorded. An intubation time difference longer than 10 seconds was defined as clinically significant.Data are reported as median; 95% confidence interval. The TTSI was similar among groups although Storz times were longer (median, 33.3 seconds; 95% confidence interval, 26.2-43.3 seconds) when compared to direct laryngoscopy (median, 23.3 seconds; 95% confidence interval, 20.7-26.5 seconds; P = 0.02). Obtaining a grade 1 Cormack-Lehane glottic view was less likely with direct laryngoscopy (P = 0.002). Maximum degrees of neck deviation were: Storz (median, 2.0; 95% confidence interval, 1.2-2.8), GlideScope (median, 2.0; 95% confidence interval, 1.4-2.6), and direct laryngoscopy (median, 1.9; 95% confidence interval, 1.2-2.1; P = 0.48).Trainees were able to safely perform tracheal intubation in children younger than 2 years using any of the studied laryngoscopes, although Storz use resulted in a longer TTSI when compared to direct laryngoscopy. Video laryngoscopy may enhance best Cormack-Lehane glottic view during manual in-line cervical spine immobilization, but additional technical skills are needed to successfully complete tracheal intubation.

Screening for pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc) is now standard care in this disease. The existing Australian Scleroderma Interest Group algorithm (ASIGSTANDARD ) is based on transthoracic echocardiography (TTE) and pulmonary function tests (PFT). Recently, ASIG has derived and validated a new screening algorithm (ASIGPROPOSED ) that incorporates N-terminal pro-B-type natriuretic peptide level together with PFT in order to decrease reliance on TTE, which has some limitations. Right heart catheterisation (RHC) remains the gold standard for the diagnosis of PAH in patients who screen 'positive'.To compare the cost of PAH screening in SSc with ASIGSTANDARD and ASIGPROPOSED algorithms.We applied both ASIGSTANDARD and ASIGPROPOSED algorithms to 643 screen-naïve SSc patients from the Australian Scleroderma Cohort Study (ASCS), assuming a PAH prevalence of 10%. We compared the costs of screening, the number of TTE required and both the total number of RHC required and the number of RHC needed to diagnose one case of PAH, and costs, according to each algorithm. We then extrapolated the costs to the estimated total Australian SSc population.In screen-naïve patients from the ASCS, ASIGPROPOSED resulted in 64% fewer TTE and 10% fewer RHC compared with ASIGSTANDARD , with $1936 (15%) saved for each case of PAH diagnosed. When the costs were extrapolated to the entire Australian SSc population, there was an estimated screening cost saving of $946 000 per annum with ASIGPROPOSED , with a cost saving of $851 400 in each subsequent year of screening.ASIGPROPOSED substantially reduces the number of TTE and RHC required and results in substantial cost savings in SSc-PAH screening compared with ASIGSTANDARD .

To determine the relationships between systemic sclerosis (SSc)-related autoantibodies, as well as their clinical associations, in a well-characterized Australian patient cohort.Serum from 505 Australian SSc patients were analyzed with a commercial line immunoassay (EuroLine; Euroimmun) for autoantibodies to centromere proteins CENP-A and CENP-B, RNA polymerase III (RNAP III; epitopes 11 and 155), the 90-kd nucleolar protein NOR-90, fibrillarin, Th/To, PM/Scl-75, PM/Scl-100, Ku, topoisomerase I (topo I), tripartite motif-containing protein 21/Ro 52, and platelet-derived growth factor receptor. Patient subgroups were identified by hierarchical clustering of the first 2 dimensions of a principal components analysis of quantitative autoantibody scores. Results were compared with detailed clinical data.A total of 449 of the 505 patients were positive for at least 1 autoantibody by immunoblotting. Heatmap visualization of autoantibody scores, along with principal components analysis clustering, demonstrated strong, mutually exclusive relationships between CENP, RNAP III, and topo I. Five patient clusters were identified: CENP, RNAP III strong, RNAP III weak, topo I, and other. Clinical features associated with CENP, RNAP III, and topo I were consistent with previously published reports concerning limited cutaneous and diffuse cutaneous SSc. A novel finding was the statistical separation of RNAP III into 2 clusters. Patients in the RNAP III strong cluster had an increased risk of gastric antral vascular ectasia, but a lower risk of esophageal dysmotility. Patients in the other cluster were more likely to be male and to have a history of smoking and a history of malignancy, but were less likely to have telangiectasia, Raynaud's phenomenon, and joint contractures.Five major autoantibody clusters with specific clinical and serologic associations were identified in Australian SSc patients. Subclassification and disease stratification using autoantibodies may have clinical utility, particularly in early disease.

V. Thakkar, W. Stevens, D. Prior, J. Byron, K. Patterson, P. Hissaria, O. Moore, J. Roddy, J. Zochling, J. Sahhar, P. Nash, K. Tymms, P. Youssef, S. Proudman and M. Nikpour Department of Rheumatology, Department of Cardiology, St Vincents Hospital, Melbourne, Royal Adelaide Hospital – Immunology Directorate, Adelaide, Department of Rheumatology, Royal Perth Hospital, Perth, Department of Rheumatology, The Menzies Institute, Hobart, Department of Rheumatology, Monash Medical Centre, Melbourne, Sunshine Coast Rheumatology – Research Unit, Maroochydore, Department of Rheumatology, Canberra Rheumatology, Canberra, Department of Rheumatology, Royal Prince Alfred Hospital, Sydney and Department of Rheumatology, Royal Adelaide Hospital, Adelaide, Australia.

Creep of nanocrystalline monoclinic zirconia, grain sizes of 75, 125, 175 nm were tested at 950 and 1000 °C. Dynamic grain growth occurred during creep but results were corrected for grain growth. Creep behavior followed an n =1.7 and p =3 behavior. It is proposed that grain boundary sliding is an active mechanism and results fit with Coble creep behavior.

The microscopic behavior of viscous materials under compaction was studied, with focus on the evolution of the pore structure with increasing pressure, at different strain rates. Granular polyethylene glycol (PEG) and high density polyethylene (HDPE) were compacted with a compaction simulator up to different pressures, at two different strain rates. Compaction curves were constructed, and diametral strength tests were performed on the tablets. Scanning electron microscopy (SEM) was used to characterize the microstructure. PEG exhibited a visco-plastic behavior, as opposed to HDPE, which behaved visco-elastically. Observation of the pore structure revealed that PEG fractured and developed rate-dependent permanent deformation, resulting in good bonding and strong tablets. On the other hand, HDPE tablets contained large pores, even at high pressures, due to the considerable amount of springback after ejection, and their diametral strength was low. For PEG, the out-of-die microstructure was strongly dependent on the strain rate, while the HDPE structure was almost independent of it. In both cases, the diametral strength and the in-die density were dependent on the strain rate. However, the effect of strain rate on diametral strength was considerably more evident for PEG than for HDPE, due to their different nature and to the resulting pore structure.

The Mars Crater Morphology Consortium recommends the use of a standardized nomenclature system when discussing Martian impact crater ejecta morphologies. The system utilizes nongenetic descriptors to identify the various ejecta morphologies seen on Mars. This system is designed to facilitate communication and collaboration between researchers. Crater morphology databases will be archived through the U.S. Geological Survey in Flagstaff, where a comprehensive catalog of Martian crater morphologic information will be maintained.

The purpose of this work was to develop a topical formulation of imiquimod, a novel immune response modifier, to induce local cytokine production for the treatment of external genital and perianal warts. A pH-solubility profile and titration data were used to calculate a pKa of 7.3, indicative of a weak base. Solubility experiments were conducted to identify a solvent that dissolves imiquimod to achieve a 5% formulation concentration. Studies to select surfactants, preservatives, and viscosity-enhancing excipients to formulate an oil-in-water cream indicated that fatty acids were the preferred solvent for topical imiquimod formulations, and isostearic acid (ISA) was selected. A relationship existed between the fatty acid composition of four commercially available ISA sources and the solubility of imiquimod. A combination of polysorbate 60, sorbitan monostearate, and xanthan gum was used to produce a physically stable cream. The preservative system included parabens and benzyl alcohol to meet the USP criteria for preservative activity. An in vitro method was developed to demonstrate that imiquimod was released from the formulation. Topical application of the formulation induced local cytokine activity in mice.

To determine the prevalence and correlates of antiphospholipid antibodies (APLA) in systemic sclerosis (SSc).Nine hundred and forty SSc patients were tested for APLA using an ELISA assay at recruitment. Clinical manifestations were defined as present, if ever present from SSc diagnosis. Logistic regression analysis was used to determine the associations of APLA.One or more types of APLA were present in 226 (24.0%) patients. Anticardiolipin (ACA) IgG (ACA-IgG) antibodies were associated with right heart catheter-diagnosed pulmonary arterial hypertension (PAH), with higher titres corresponding with a higher likelihood of PAH (moderate titre (20-39 U/ml) ACA-IgG odds ratio [OR] 1.70, 95% CI: 1.01-2.93, p=0.047; high titre (40 U/ml) ACA-IgG OR 4.60, 95% CI:1.02-20.8, p=0.047). Both ACA-IgM (OR 2.04, 95% CI: 1.4-3.0, p0.0001) and ACA-IgG (OR 1.84, 95% CI: 1.2-2.8, p=0.005) were associated with interstitial lung disease (ILD). Increasing ACA-IgM and IgG titres were associated with increased likelihood of ILD. ACA-IgG was a marker of coexistent pulmonary hypertension and ILD (ILD-PH) (OR 2.10, 95% CI: 1.1-4.2, p=0.036). We also found an association between ACA-IgG and digital ulcers (OR 1.76, 95% CI: 1.16-2.67, p=0.008) and ACA-IgM and Raynaud's phenomenon (OR 2.39, 95% CI: 1.08-5.27, p=0.031). There was no association between APLA and SSc disease subtype, peak skin score, presence of other autoantibodies, mortality or other disease manifestations.The association of APLA with PAH, ILD, ILD-PH, Raynaud's phenomenon and digital ulcers suggests that endothelial abnormalities and small vessel thrombosis may be important in the pathogenesis of these disease features.

Preliminary 2D/3D numerical simulations were carried out for the penetration of 1-km bodies in the Jovian atmosphere and the subsequent rise and collapse of the erupted plumes. A body that crushed at a stagnation point pressure of 5 kbar produced a plume that rose to 800 km. Evolution of the shape of the calculated plume corresponds rather well to the plumes observed by HST. A crescent-shaped lobe centered on the “backfire” azimuth was produced by lateral flow during plume collapse. The plumes observed on Jupiter rose about 4 times higher, and their rise and fall times were about twice those in this calculation. Plume height is a sensitive function of the distribution of energy along the entry path; a very low-strength body will disintegrate higher along the penetration path and will produce a higher plume.

Rodent oligodendrocytes have a unique susceptibility among glia to the lytic effects of complement, due in part to a deficiency in CD59 (protectin), a key surface inhibitor of the complement membrane attack complex (MAC). The possibility that shedding of CD59 by human oligodendrocytes contributes to complement-mediated oligodendrocyte injury in inflammatory demyelinating disease has been investigated by estimating levels of CD59 in cerebrospinal fluid samples from 12 patients with demyelinating disease of the central nervous system and 13 with other neurological diseases. No significant differences were found between patients and controls, or between patients with active and those with clinically inactive demyelinating disease, providing no direct support for oligodendrocyte shedding of CD59 in multiple sclerosis.

The East Kirkton Limestone is typically a carbonate/organic laminite characterised at many levels by abundant radial-fibrous calcite (RFC) spherules and by less common larger stromatolite-like accretions of laminated botryoidal RFC. The spherules are mostly c. 1 mm in diameter and have cyanophyte and chlorophyte inclusions. Some spherules enclose parallel bundles of complete cyanophyte fibres and probably grew within a living cyanophyte mat. The botryoidal accretions were commonly seeded upon wood and other exposed organic remains such as bone, and they completely enclose twigs and branches where these were held above the sediment surface. Botryoidal accretions commonly contain the remains of a benthos of cyanophytes, chlorophytes and ostracods.Both types of calcite have carbon and oxygen stable isotope values similar to those of known fresh-water precipitates. Their stable isotope and trace element geochemistries are consistent with precipitation on the floor of a tropical fresh-water lake within a volcanic setting, but removed from the influence of any hot-spring activity. Spherules and botroids are mineralogically closely similar and, whilst precipitation may have been biogenically mediated, they are regarded as passive lake floor cements.The carbonate laminae are dominated by rhombohedral calcite. Many of these laminae may have originated as calcite suspensoids which settled to the lake floor during relatively brief precipitation events, blanketing the normally richly organic substrate, smothering the cyanophyte mats, and leading to the preservation of individual organic laminae. Crystals later became enlarged and intergrown within the sediment, but this occurred early and prior to significant compaction, because detail of fragile and degradable organic constituents is commonly preserved. The likely source of the carbonate is through leaching of the local basic volcanic terrain. The precipitation of two types of calcite implies regular fluctuations in the chemistry of the lake waters, or in the factors controlling precipitation, which may have been a biogenic and/or seasonal effect.

Using cosmogenic 36 Cl buildup and rock varnish radiocarbon, we have measured the exposure age of rock surfaces at Meteor Crater, Arizona. Our 36 Cl measurements on four dolomite boulders ejected from the crater by the impact yield a mean age of 49.7 ± 0.85 ka, which is in excellent agreement with an average age of 49 ± 3 ka obtained from thermoluminescence studies on shock-metamorphosed dolomite and quartz. These ages are supported by undetectably low 14 C in the oldest rock varnish sample.

Eleven people were killed and 60 injured in the Enniskillen bombing of November 1987. Survivors were psychologically appraised six months and one year later. At six months 50% had developed post-traumatic stress disorder (PTSD). This group comprised more females than males. However, all victims had high scores on the GHQ. We found no correlation between psychological injury (as measured by the GHQ) and physical injury (as measured by the ISS), calling into question previous assertions.

We describe a Japanese Canadian woman who presented with scleroderma and tuberculosis. We discuss the possible association between these 2 diseases.

Two three-way crossover studies were done to characterize the drug release characteristics of Monospan (3M Pharmaceuticals, St. Paul, MN) capsules, a new once-a-day theophylline formulation. In the first study, 22 healthy males received single 450-mg doses of Monospan in the presence and absence of a high-fat breakfast; the same dose of Somophyllin (Fisons, Rochester, NY) immediate-release liquid was given to fasted subjects as a reference. The second study involved 29 healthy males given a single dose of 900 mg of Monospan in the presence and absence of the same high-fat meal; Theo-24 (G. D. Searle and Co., Skokie, lL) capsules were given to fasted subjects as a reference. The results of both studies showed that food did not affect the absorption of theophylline from Monospan; peak concentration, time to peak concentration, and area under the serum concentration-time curve were all unchanged. The absorption rates were similar with both strengths and dietary conditions and showed that theophylline was absorbed slowly from Monospan at a constant rate (~3.2%/h) over 24 h. Absorption continued past 24 h, and the extent of absorption from Monospan compared with that from each reference averaged 88% or higher. A good correlation (r > 0.980) was observed for Monospan between the amount absorbed in vivo and the amount released in the in vitro dissolution test, a result that demonstrates the precise rate control of Monospan. We conclude that Monospan is a suitable once-a-day formulation that can be taken without regard to food.

Computer simulations have been completed that describe passage of a 10-km-diameter asteroid through the Earth's atmosphere and the subsequent cratering and ejecta dynamics caused by impact of the asteroid into both oceanic and continental sites. The asteroid was modeled as a spherical body moving vertically at 20 km/s with a kinetic energy of 2.6 × 1030 ergs (6.2 × 107 Mt ). Detailed material modeling of the asteroid, ocean, crustal units, sedimentary unit, and mantle included effects of strength and fracturing, generic asteroid and rock properties, porosity, saturation, lithostatic stresses, and geothermal contributions, each selected to simulate impact and geologic conditions that were as realistic as possible. Calculation of the passage of the asteroid through a U.S. Standard Atmosphere showed development of a strong bow shock wave followed by a highly shock compressed and heated air mass. Rapid expansion of this shocked air created a large low-density region that also expanded away from the impact area. Shock temperatures in air reached ∼20, 000K near the surface of the uplifting crater rim and were as high as ∼2000K at more than 30 km range and 10 km altitude. Calculations to 30 s showed that the shock fronts in the air and in most of the expanding shocked air mass preceded the formation of the crater, ejecta, and rim uplift and did not interact with them. As cratering developed, uplifted rim and target material were ejected into the very low density, shock-heated air immediately above the forming crater, and complex interactions could be expected. Calculations of the impact events showed equally dramatic effects on the oceanic and continental targets through an interval of 120 s. Despite geologic differences in the targets, both cratering events developed comparable dynamic flow fields and by ∼29s had formed similar-sized transient craters ∼39km deep and ∼62km across. Transient-rim uplift of ocean and crust reached a maximum altitude of nearly 40 km at ∼30s and began to decay at velocities of 500 m/s to develop large-tsunami conditions. After ∼30s, strong gravitational rebound drove both craters toward broad flat-floored shapes. At 120 s, transient crater diameters were ∼80km (continental) and ∼105km (oceanic) and transient depths were ∼27km; crater floors consisting of melted and fragmented hot rock were rebounding rapidly upward. By 60 s, the continental crater had ejected ∼2 × 1014t, about twice the mass ejected from the oceanic crater. By 120 s, ∼70, 000km3 (continental) and ∼90, 000km3 (oceanic) target material were excavated (no mantle) and massive ejecta blankets were formed around the craters. We estimate that in excess of ∼70% of the ejecta would finally lie within ∼3 crater diameters of the impact, and the remaining ejecta (∼1013t), including the vaporized asteroid, would be ejected into the atmosphere to altitudes as high as the ionosphere. Effects of secondary volcanism and return of the ocean over hot oceanic crater floor could also be expected to contribute substantial material to the atmosphere.