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Familial partial lipodystrophy (FPLD) is a rare and heterogenous disease without gold-standard diagnostic criteria. The heterogeneity applies to fat distribution, symptomatology, metabolic complications, and genetic etiology. Disease heterogeneity has contributed to the lack of standardized diagnostic criteria, an obstacle to understanding both the natural history of the disease and response to therapies. We have assessed whether DXA data can aid in disease diagnosis. DXA scans quantify fat and lean mass in the whole body, arms, legs, and trunk. An increased ratio of fat percentage in the trunk to the legs (termed "trunk-leg ratio", TLR) has been proposed as an objective method to detect FPLD. Using large sets of DXA data from control subjects, along with data from FPLD subjects, we sought to improve upon TLR. We hypothesized that TLR might change as a function of overall adiposity (total body fat, TF). Females were studied first because of the high female: male ratio of disease prevalence observed in FPLD. In 2713 control females with DXA measurements within the UKBiobank (UKB), TLR increased linearly as a function of TF until a TF of ∼36% and then the TLR plateaued with higher TF. We analyzed published DXA data of FPLD subjects from the USA (n=55).1 FPLD subjects had higher TLRs than controls at each level of adiposity. Due to the non-linear relationship between total adiposity and TLR, two linear fits were generated to best discriminate controls from FPLD subjects for a given adiposity. For females with body fat TF*0.0311+0.232. For females with body fat ≥36%, the algorithm predicts FPLD if TLR >1.353. After training on this UKB data set, we tested the algorithm on independent data sets of control females from NHANES (n=2347) and FPLD subjects (n=37, from the NIH). The algorithm had a sensitivity of 92–97% and a specificity of 99.3%. This degree of specificity is still not sufficient for implementation of rare disease screening in the general population, but could be useful in a population with increased pre-test probability of having FPLD such as non-obese individuals with Type 2 diabetes and/or hypertriglyceridemia. Because race and ethnicity are possible modifiers of body fat distribution, we examined the relationship between TF and TLR across ethnic and racial groups in NHANES. Mexican-Americans (n=659), Hispanic-other (n=81), White (n=871), Black (n=612), and other/biracial (n=124) subjects from NHANES had a similar relationship between adiposity and TLR. Therefore, the same DXA criteria can be applied across these ethnicities. In summary, the relationship between adiposity and TLR may be used to aid in the diagnosis of FPLD in females. Reference Meral R, et al. Diabetes Care. 2018;41,2255–2258. Presentation: Saturday, June 11, 2022 1:06 p.m. - 1:11 p.m., Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.

Background New treatments are being evaluated for lipodystrophy; however, limited information is available on the patient experience. Results of a prior patient panel showed that hunger and temperature-related symptoms were an issue for participants. Therefore, evaluation of any changes in these symptoms is recommended for inclusion in new treatment options. The objective of this study was to further understand the patient experience and to evaluate newly developed items of hunger and temperature regulation. Methods Individual, in-depth telephone interviews were conducted via semi-structured discussion guide. Telephone interviews were conducted with 21 US patients with generalized lipodystrophy (GLD) or partial lipodystrophy (PLD). Eligibility requirements included self-reported PLD or GLD. Interviews included open-ended concept elicitation followed by a review of newly developed items assessing hunger, temperature sensations, and patient globals. Interviews were conducted in two rounds, with the newly developed items assessing hunger revised after each round of interviews based on participant feedback. Results Results indicated that hunger-related symptoms were considered a current issue for greater than half (N = 11) of participants, and all but one reported this as an issue at some point in their lives. Specifically, participants most often reported symptoms of increased appetite and not feeling full. The cognitive debriefing process indicated that the hunger-related symptoms, temperature, and global impression of change and severity items were correctly interpreted and easily completed by the participants. While not a focus of the interviews, the concept elicitation results demonstrated that pain was a frequently reported and bothersome symptom in this patient population. Conclusions This qualitative research provided evidence to support the use of clinical outcomes assessments such as hunger and temperature-related items in clinical trials.

BACKGROUND Numerous advancements in hemorrhage control and volume replacement that comprise damage control resuscitation (DCR) have been implemented in the last decade to reduce deaths from bleeding. We sought to determine the impact of DCR interventions on mortality over 12 years in a massive transfusion protocol (MTP) population. We hypothesized that mortality would be decreased in later years, which would have used more DCR interventions. STUDY DESIGN This was a retrospective review of all MTP patients treated at a large regional Level I trauma center from 2008 to 2019. Interventions by year of implementation examined included MTP 1:1 ratio (2009), liquid plasma (2010), tranexamic acid (2012), prehospital tourniquets (2013), REBOA/TEG (2017), satellite blood station (2018), and whole blood transfusion (2019). Relative risk and odds of mortality for DCR interventions were examined. RESULTS There were 824 MTP patients included. The cohort was primarily male (80.6%) injured by penetrating mechanism (68.1%) with median (interquartile range) age 31 years (23-44) and New Injury Severity Score 25 (16-34). Overall mortality was unchanged [(38.3%-56.6%); P = 0.26]. Tourniquets (P = 0.02) and whole blood (WB) (P = 0.03) were associated with lower unadjusted mortality; only tourniquets remained significant after adjustment (OR: 0.39; 95% CI: 0.17-0.89; P = 0.03). CONCLUSIONS Despite lower mortality with use of tourniquets and WB, mortality rates due to hemorrhage have not improved at our high MTP volume institution, suggesting implementation of new in-hospital strategies is insufficient to reduce mortality. Future efforts should be directed toward moving hemorrhage control and effective resuscitation interventions to the injury scene.

Background How the surgical stabilization of rib fractures after trauma affects the development of acute respiratory distress syndrome and impacts survival has yet to be determined in a large database. We hypothesized that surgical stabilization of rib fractures would not decrease the incidence of acute respiratory distress syndrome. Methods The National Trauma Data Bank was queried for all traumatic rib fractures in 2016. Patients were divided into groups with single rib fractures, multiple rib fractures, and flail chest. Nonoperative therapy was compared with stabilization of rib fractures of 1 to 2 ribs or 3+ ribs. Results There were 114,972 total patients with rib fractures meeting inclusion criteria, with 5,106 (4.4%) having flail chest, 24,726 (21.5%) having single rib fractures, and 85,140 (74.1%) having multiple rib fractures. Those with flail chest (15.9%) were most likely to get rib plating in comparison to multiple rib fractures (0.9%) and single rib fractures (0.2%); P < .001. On logistic regression, surgical stabilization of rib fractures 1 to 2 ribs (odds ratio: 0.17, 95% confidence interval: 0.10–0.28) or 3+ ribs (odds ratio: 0.17, 95% confidence interval: 0.11–0.28), with nonoperative therapy as the reference was associated with survival. Variables associated with mortality included increasing age, male sex, increasing injury severity score, decreased Glasgow coma scale, requirement of transfusions, and hypotension on admission. Surgical stabilization of rib fractures 3+ ribs (odds ratio: 2.30, 95% confidence interval: 1.58–3.37) was associated with acute respiratory distress syndrome but not 1 to 2 ribs (odd ratio: 1.55, 95% confidence interval: 0.97–2.48). On logistic regression of only patients with flail chest, stabilization of rib fractures was associated with decreased mortality but not increased risk of acute respiratory distress syndrome. Conclusion The increased risk of acute respiratory distress syndrome should be considered in the preoperative assessment for stabilization of rib fractures.

INTRODUCTION Recent studies have suggested the female hypercoaguable state may have a protective effect in trauma. However, whether this hypercoagulable profile confers a survival benefit in massively transfused trauma patients has yet to be determined. We hypothesized that females would have better outcomes than males after traumatic injury that required massive transfusion protocol (MTP). PATIENTS AND METHODS All trauma patients who underwent MTP at an urban, level 1, academic trauma center were reviewed from November 2007 to October 2018. Female MTP patients were compared to their male counterparts. RESULTS There were a total of 643 trauma patients undergoing MTP. Of these, 90 (13.8%) were female and 563 (86.2%) were male. Presenting blood pressure, heart rate, shock index, and injury severity score (ISS) were not significantly different. Overall mortality and incidence of venous thromboembolism were similar. Complication profile and hospital stay were similar. On logistic regression, female sex was not associated with survival (HR: 1.04, 95% CI: 0.56-1.92, P = 0.91). Variables associated with mortality included age (HR: 1.02, 95% CI: 1.05-1.09, P = 0.03) and ISS (HR: 1.07, 95% CI: 1.05-1.09, P

Plastic pots were inserted beneath seedlings of a shallow-rooted C4grass species, Ischaemum indicum, with and without a root-impenetrable nylon sachet filled with organic matter (OM) amendment, at seven stations along an interrupted belt transect in which plant community and soil chemistry had been previously surveyed. The transect was perpendicular to mean high-water mark (MH-WM) across a primary coastal dune system in Goa, India, where summer monsoon is the predominant weather feature. The Quadrat survey of plant frequency was made in stations when the above-ground biomass was estimated to be highest. Arbuscular mycorrhiza fungal (AMF) spore density and diversity were determined morphologically in amended and control pots soils, and in OM sachet residues, after host-plant desiccation when monsoon rains had ceased. Twenty-seven AM fungal spore morphotypes were isolated from the pots containing OM amended rhizosphere soils, 19 from controls and 14 from OM residues in the sachets. Gigaspora margarita proved to be the dominant spore in all treatments. Eight morphotypes recovered from amended pots were not recovered from the controls. There was an increasing trend in species diversity in amended pots away from MH-WM. Spore recovery from the three regimes showed variable distribution that indicated differing AMF species strategies.

Ring slip is among the most widely invoked ligand distortions in organometallic chemistry, yet very few ring slipped geometries have been directly characterized. Here we investigate the ultrafast photochemistry of (η1-C5Cl5)Mn(CO)5 to characterize the “reverse ring-slip” processes that result upon ligand dissociation from this complex in polar and nonpolar solvents. (η1- C5Cl5)Mn(CO)5 readily undergoes dicarbonyl-loss upon photoexcitation across a range of UV-excitation wavelengths, and the fac- ile ejection of a second-CO during the reverse ring-slip process is shown to occur due to a mechanism that relies on the enthalpy released during the reverse ring-slip. This mechanistic paradigm is potentially widespread in organometallic reactions involving changes in ligand hapticity, carrying implications for the expansive range of Cp-ligated organometallic complexes. Experiments in CH2Cl2 solution observe formation of a solvent-coordinated product upon coordination of CH2Cl2 to the monocarbonyl-loss spe- cies. An energetic barrier to solvent coordination is present due to the need for rearrangement of the ring geometry from a three- center M-C-Cl coordination to η1 coordination to accommodate the incoming solvent molecule. Density functional theory calculations are used to investigate the structures of the experimentally observed intermediates, as well as to explore the relevance of these experiments to analogous complexes containing the more commonly encountered Cp (C5H5) and Cp* (C5Me5) cyclopentadienyl ligands.

The primary photochemical dynamics of [Cp*Cr(CO)2]2 have been studied using picosecond time-resolved infrared (TRIR) spectroscopy. Upon visible or UV photoexcitation, the primary photochemical pathway is formation of a transient rear- rangement isomer with a weakened Cr≡Cr bond and two terminal carbonyl ligands rearranged to a bridging conformation. This species reverts to the parent dimer on the time scale of 378 ± 15 ps, and Density Functional Theory calculations suggest that this transient species is characterized by a triplet spin state and a trans conformation of the two terminal CO ligands. Photolysis in neat THF solution is unable to trap the transient intermediate via solvent-coordination. The excited state transient rearrangement isomer appears to adopt a distorted structure in THF, relative to cyclohexane, evidenced by the observation of an additional bridging-CO stretching band in THF solution. The lifetime of the transient in THF is just slightly shorter at 344 ± 17 ps. The CO-loss product of 1 has been characterized previously and adopts an asymmetric arrangement of the three bridging CO ligands. In neat THF solution, the CO-loss complex is not observed to react with THF on the picosecond timescale, although a previous study on longer timescales observed formation of a THF adduct of the CO-loss complex in dilute alkane/THF solutions. Though the molybdenum congener, [Cp*Mo(CO)2]2, is unstable in solution, decaying on the timescale of a few hours in cyclohexane, TRIR experiments demonstrate that no bridged photoproducts (transient or long-lived) are formed from the Mo complex in cyclohexane solution.

Spin state changes frequently play a key role in the reactivity of transition metal complexes. The rates of spin-forbidden reactions are mediated both by the free energy barrier connecting reactants and products, as well as the strength of spin-orbit coupling (SOC) between the relevant electronic states. Since the 1950’s, there have been numerous demonstrations of external heavy-atom effects on organic molecules, in which a heavy atom, not chemically bonded to the molecule undergoing a change in spin state, perturbs the strength of SOC via an intermolecular effect. However, the potential role of external heavy atom effects on the rates of reactions involving transition metal complexes remains almost entirely unexplored. We report a computational investigation into the changes in SOC that occur along a bimolecular reaction coordinate when an incoming atom coordinates to the prototypical triplet reaction intermediate Fe(CO)4. The calculated changes in SOC are compared for molecules containing atoms ranging in atomic number from Z = 8 to Z = 53 approaching the Fe center (ZFe =26). No evidence for an external heavy atom effect was found, and the changes in SOC with the approach of each incoming group were similar in magnitude. In fact, when taking into account the different minimum energy crossing point geometries for the different incoming groups, the opposite of an external heavy atom effect trend is predicted for this reaction. The results of this computational study suggest that external heavy atom effects are unlikely to have a significant effect on the rates of spin-forbidden reactions for transition metal complexes.

Background: Cognitive symptoms are some of the most distressing for patients who are depressed. The goal was to investigate whether depressed patients’ cognition changed depending on treatment with SSRIs (No-NOR) vs. Norepinephrine-enhancing medications (NOR) during an inpatient stay. Methods: This was an observational, naturalistic, pilot study that used a repeated measures design. 119 depressed inpatients, average age 39 years, 61% females, 77% Caucasian, 74% with mood disorders, 50% Cluster B traits/disorders and 32% psychoactive substance abuse disorders participated. The Trail Making Test (TMT), Hamilton Depression Rating Scale (HDRS), and Outcome Questionnaire-45(OQ-45) were used. Results: Revealed significant differences between admission and discharge in HDRS (MA=24, MD=9, t (98)=25.30, p

Leak rate testing has been performed using Alloy 600 tube specimens with throughwall flaws. Some specimens have shown time-dependent leak behavior at constant pressure conditions. Fractographic characterization was performed to identify the time-dependent crack growth mechanism. The fracture surface of the specimens showed the typical features of ductile fracture, as well as the distinct crystallographic facets, typical of fatigue crack growth at low Δ K level. Structural vibration appears to have been caused by the oscillation of pressure, induced by a high-pressure pump used in a test facility, and by the water jet/tube structure interaction. Analyses of the leak behaviors and crack growth indicated that both the high-pressure pump and the water jet could significantly contribute to fatigue crack growth. To determine whether the fatigue crack growth during the leak testing can occur solely by the water jet effect, leak rate tests at constant pressure without the high-pressure pump need to be performed.

We present a review of the changing state of European permafrost within a spatial zone that includes the continuous high latitude arctic permafrost of Svalbard and the discontinuous high altitude mountain permafrost of Iceland, Fennoscandia and the Alps. The paper focuses on methodological developments and data collection over the last decade or so, including research associated with the continent-scale network of instrumented permafrost boreholes established between 1998 and 2001 under the European Union PACE project. Data indicate recent warming trends, with greatest warming at higher latitudes. Equally important are the impacts of shorter-term extreme climatic events, most immediately reflected in changes in active layer thickness. A large number of complex variables, including altitude, topography, insolation and snow distribution, determine permafrost temperatures. The development of regionally calibrated empirical-statistical models, and physically based process-oriented models, is described, and it is shown that, though more complex and data dependent, process-oriented approaches are better suited to estimating transient effects of climate change in complex mountain topography. Mapping and characterisation of permafrost depth and distribution requires integrated multiple geophysical approaches and recent advances are discussed. We report on recent research into ground ice formation, including ice segregation within bedrock and vein ice formation within ice wedge systems. The potential impacts of climate change on rock weathering, permafrost creep, landslides, rock falls, debris flows and slow mass movements are also discussed. Recent engineering responses to the potentially damaging effects of climate warming are outlined, and risk assessment strategies to minimise geological hazards are described. We conclude that forecasting changes in hazard occurrence, magnitude and frequency is likely to depend on process-based modelling, demanding improved understanding of geomorphological process-response systems and their impacts on human activity.

Results are presented from eight scaled centrifuge modelling experiments designed to investigate mass movement processes on thawing ice-rich slopes. Four pairs of simple planar slope models were constructed, one in each pair being of sufficient gradient to promote slope failure during soil thaw and the second having a gradient below the threshold for instability. Four frost susceptible soils were used, three were normally consolidated and had different clay contents (2%, 12% and 20%) and the fourth comprised the 20% clay soil, but was over consolidated prior to model testing. Modelling protocols included freezing from the surface downwards under an open hydraulic system, and thawing from the surface downwards under an enhanced gravitational field within the geotechnical centrifuge, thereby utilising scaling laws to simulate correct prototype self weight stresses during thaw. Slopes below the stability threshold gradient were subjected to between 2 and 4 cycles of freezing and thawing, simulating annual cycles. Those above the stability threshold were subjected to only one cycle, since they failed during the first thaw phase. Thermal conditions, pore water pressures, surface movements, and profiles of displacement are reported. Measured pore pressures are used in slope stability analyses based on a simple planar infinite slope model. Profiles of solifluction shear strain and mechanisms of slope failure are both shown to be sensitive to small changes in soil properties, particularly clay content and stress history. In all cases, pore pressures rose rapidly immediately following thaw, remained below the threshold for failure in low gradient models, but exceeding the threshold to trigger landslides on steeper slopes. Upward seepage of melt water away from the thaw front contributed to loss of shear strength. Mechanisms of slope failure differed between test soils, ranging from mudflow in non-cohesive silt to active layer detachment sliding in over consolidated silt–clay. During solifluction, shear strain was greatest at the surface in non-cohesive silt and decreased rapidly with depth, but in test soils containing clay, the zone of maximum shear strain was located lower in the displacement profiles.

High doses of the nicotinic acetylcholine receptor (nAChR) antagonist mecamylamine can elicit somatic signs resembling those associated with nicotine withdrawal in nicotine-naïve adult rats. Understanding this phenomenon, and its possible modulation by acute nicotine and age, could inform the use of mecamylamine as both an experimental tool and potential pharmacotherapy for tobacco dependence and other disorders. This study evaluated the ability of high-dose mecamylamine to elicit somatic signs in adolescent rats, and the potential for acute nicotine pretreatment to potentiate this effect as previously reported in adults. Single or repeated injections of mecamylamine (1.5 or 3.0 mg/kg, s.c.) elicited somatic signs in nicotine-naive adolescents, but this effect was not influenced by two hour pretreatment with acute nicotine (0.5 mg/kg, s.c.). In an initial evaluation of the effects of age in this model, mecamylamine (2.25 mg/kg, s.c.) elicited somatic signs in nicotine-naive adolescents and adults. This effect was modestly enhanced following acute nicotine injections in adults but not in adolescents, even when a higher nicotine dose (1.0 rather than 0.5 mg/kg, s.c.) was used in adolescents to account for age differences in nicotine pharmacokinetics. These studies are the first to show that mecamylamine elicits somatic signs in nicotine-naïve adolescent rats, an effect that should be considered when designing and interpreting studies examining effects of high doses of mecamylamine in adolescents. Our findings also provide preliminary evidence that these signs may be differentially modulated by acute nicotine pretreatment in adolescents versus adults.

Here we interpret the outcomes of scaled geotechnical centrifuge simulation of ice-wedge casting in terms of the likely significance of Quaternary ice-wedge pseudomorphs observed within different host sediments. Six experiments were completed in which 1/30th scale models of an ice-wedge embedded within frozen host sediments beneath a 25 mm thick unfrozen active layer were thawed from the surface downwards in the geotechnical centrifuge under a 30 times gravity (30A—g) acceleration. Host sediment granulometry and/or ice contents were varied in each model, with host materials comprising medium sands, fine sandy silts and silty clays. The model ice-wedge was 50 mm at the top, 150 mm deep, and extended across the full width of the 450 mm wide test box. Centrifuge scaling laws indicate that under an acceleration of 30A—g, stress distribution was equivalent to a 13.5 m long section of a 4.5 m high and 1.5 m wide full-scale prototype ice-wedge, covered in an active layer of thickness equivalent to 0.75 m. Thermal regimes, measured pore pressures during thaw, observed thaw consolidation and measured host sediment geotechnical properties are utilised in the interpretation of casting mechanisms. During a single uniform thaw event it is shown that arching of infilling sediment and the formation of a void is likely if negative pore pressures are developed in the host sediment. In fine silt and clays high ice contents are more likely than in sands, thaw consolidation is greater, positive pore pressures encourage complete filling of the ice-wedge void, and soft sediment deformation is likely to cause deformation of the cast and reduce its width and depth. Though natural casting mechanisms are likely to be more complex than those simulated here, modelling experiments highlight the need for care when inferring original ice-wedge geometry from observed shape and size of Quaternary ice-wedge casts.

Fifty active-layer detachment failures triggered after forest fire in the discontinuous permafrost zone (central Mackenzie Valley, 65° N.) are compared to several hundred others caused by summer meteorological triggers in continuous permafrost (Fosheim Peninsula, Ellesmere Island, 80°N). Most failures fall into compact or elongated morphological categories. The compact type occur next to stream channels and have little internal disturbance of the displaced block, whereas the elongated types can develop on any part of the slope and exhibit greater internal deformation. Frequency distributions of length-to-width and length-to-depth ratios are similar at all sites. Positive pore pressures, expected theoretically, were measured in the field at the base of the thawing layer. Effective stress analysis could predict the instability of slopes in both areas, providing cohesion across the thaw plane was set to zero and/or residual strength parameters were employed. The location of the shear planes or zones in relation to the permafrost table and the degree of post-failure secondary movements (including headwall recession and thermokarst development within the failure track) differed between the localities, reflecting dissimilarity in the environmental triggers and in the degree of ground thermal disturbance.

This paper demonstrates the capabilities and limitations of a miniaturised electrical imaging technique (resistivity tomography) developed at Cardiff University to image contaminant plumes in scaled centrifuge models of the vadose zone. For this purpose a generic model of contaminant infiltration into unsaturated sand was designed. The imaging technique produces two-dimensional contoured plots of the resistivity distribution before and during contaminant infiltration experiments. During the experiments, dyed NaCl solution was released into the model and the change in resistivity associated with the contaminant plume evolution was imaged as a function of time and g -level. Capillary pressure was monitored constantly by matrix potential probes (tensiometers) in order to investigate the effect of capillary forces on plume evolution. Tests at 1 g (static conditions) and 10 g are described in this paper. Comparison of resulting two-dimensional tomography with observed plume geometry at the end of the 1 g test showed this imaging technique to be highly effective. Contaminant plume evolution in the unsaturated sand model was observed to be mainly gravity-driven, with plume migration and geometry being strongly affected by a tenfold increase in gravity in the centrifuge experiment. It is concluded that miniaturised electrical imaging can be a useful tool for monitoring pollution plume evolution during centrifuge tests, but when plume evolution is rapid, the time taken to interrogate each array restricts the effectiveness of the technique in monitoring changes in plume geometry. However, in such cases, resistivity tomography does provide valuable information on residual levels of contaminant fluid retained within the soil after passage of the plume.

Despite extensive field studies, progress in understanding gelifluction processes has been limited. Controlled laboratory simulation experiments offer an alternative and potentially extremely effective approach. Such an experiment is described here. It was conducted on a 12? slope formed of two natural soils, one a fine sandy silt derived from slate bedrock, the second a gravelly silty sand derived from mudstone bedrock. Continuous measurements were made of soil temperatures, porewater pressures, frost heave, thaw settlement, and downslope displacements of the soil surface over seven freeze/thaw cycles. Two-dimensional vectors of soil surface movements together with evidence from excavated displacement columns suggest that gelifluction occurred only during thaw consolidation of the upper parts of the soil profile; thawing of the deeper layers caused thaw consolidation but little downslope displacement. Cryogenic processes are shown to cause progressive decreases with depth in void ratio and moisture content and increases in undrained shear strength within the continuous soil matrix that separates ice lenses. Since self-weight stress levels are low, thawing leads to significant shear strain only in the softer, wetter near-surface soil layers.

Active-layer detachment slides are locally common on Fosheim Peninsula, Ellesmere Island, where permafrost is continuous, the active layer is 0.5-0.75 m thick, and summer temperatures are unusually high in comparison with much of the Canadian High Arctic. In this paper we report pore-water pressures at the base of the active layer, recorded in situ on two slopes in late July and early August 1995. These data form the basis for slope stability analyses based on effective stress conditions. During fieldwork, the factor of safety within an old detachment slide on a slope at Hot Weather Creek was slightly greater than unity. At "Big Slide Creek," on a slope showing no evidence of earlier detachment failures, the factor of safety was less than unity on a steep basal slope section but greater than unity elsewhere. In the upper slope, pore-water pressures were only just subcritical. Sensitivity analyses demonstrate that the stability of the shallow active layer is strongly influenced by changes in soil shear strength. Possible mechanisms for reduction in shear strength through time include weathering of soils and gradual increases in basal active layer ice content. However, we suggest here that soil shearing during annual gelifluction movements is most likely to progressively reduce shear strengths at the base of the active layer from peak values to close to residual, facilitating the triggering of active-layer detachment failures.Key words: detachment slides, Ellesmere Island, pore-water pressures, gelifluction.

Here we compare scaled centrifuge modelling of gelifluction processes with earlier full-scale physical modelling experiments. The objective is to assess the validity of the centrifuge technique for cryogenic slope-process investigations. Centrifuge modelling allows correct self-weight stresses to be generated within a small-scale physical model by placing it in an elevated gravitational field. This paper describes an experiment in which a scaled frozen-slope model was thawed in a gravitational field equivalent to ten gravities. After four cycles of thawing, during which soil temperatures, pore pressures, thaw settlement and downslope soil displacements were continuously monitored, a series of marker columns were excavated to reveal profiles of soil movement. Comparison of these data with those from an earlier full-scale laboratory simulation experiment indicates that thaw-related gelifluction was successfully reproduced during centrifuge modelling. It is concluded that rates of soil shear strain during gelifluction were not time-dependent? since soil displacements in the centrifuge tests were of a similar magnitude to or greater than those observed in the much longer-duration full-scale simulation. This suggests that no transition occurred in soil behaviour from a frictional plastic to a true viscous fluid during the period of high moisture contents immediately following thaw.

To assess the safety against failure of rock slopes in cold regions, such as high mountain areas, where stability is potentially maintained by ice in rock discontinuities, the shear strength of ice-filled rock joints was investigated in a series of direct shear-box tests. To permit control and repeatability, the experiments were conducted using simulated rock specimens. These were cast in the laboratory using high-strength concrete. Laboratory measurements showed that at a constant rate of shearing, the interface shear strength between ice and a joint surface of repeatable roughness is a function of both temperature and normal stress.

Rupture of an abdominal aortic aneurysm (AAA) can be a catastrophic event for a patient, with many patients who rupture dying before they ever make it to the hospital for assessment. Once assessed and treated, patients are by no means out of the woods, as the overall mortality for patients undergoing repair of AAA is still quite high post-intervention. Here we present an interesting case of a 62 year old African-American male who presented to our community hospital with a ruptured AAA measuring 11 cm at its maximum diameter. This is one of the largest ruptured AAA's to ever be reported in the literature. We treated this patient with endovascular placement of stent-grafts, making this one of the largest ever endovascular repairs undertaken. This patient made an optimal recovery post-intervention and is alive and well today.

[EN] None of the nucleus replacement implants developed so far has been able to mimic the biomechanical behaviour of the natural intervertebral disc. For that reason, the company NEOS Surgery, the technological centers ASCAMM and IBV and Sant Pau Hospital, have worked together on the European project CUSTOM-IMD to develop an innovative nucleus replacement implant that better fits to the patients needs. The most important features of this new implant are customization of design, responding to the specific needs of each patient; and the ability of easy implantation with minimally invasive surgery, shortening the postoperative recovery and improving the patient¿s function., [ES] Ninguna de las prótesis de núcleo desarrolladas hasta la fecha es capaz de reproducir el comportamiento biomecánico del disco intervertebral natural y, por este motivo, la empresa NEOS Surgery, los centros tecnológicos ASCAMM e IBV y el Hospital Sant Pau, han trabajado conjuntamente en el proyecto europeo CUSTOMIMD para desarrollar una novedosa prótesis para la sustitución del núcleo pulposo que responda mejor a las necesidades de los pacientes. Las características más destacables de esta prótesis son su diseño personalizado, dando respuesta a las necesidades específicas de cada paciente, y su facilidad de implantación mediante cirugía mínimamente invasiva, acortando así el tiempo de recuperación postoperatorio y mejorando la recuperación funcional del paciente., El desarrollo de esta prótesis ha sido financiado por la Comisión Europea, dentro del VI Programa Marco para I+D, en el marco del proyecto CUSTOM-IMD (NMP3-CT-2007-026599), coordinado por ASCAMM Centro Tecnológico.

Three recent shallow landslides over permafrost are described. Slides occur in low- to medium-plasticity clays containing some bands of silts and fine sands. Slope failure results from rapid thaw at the base of the active layer of soil that is ice-rich due to antecedent two-sided freezing. Displaced slide blocks retain their integrity because of hardening of the active layer by cryodesiccation and summer evaporation. Blocks move over a soft basal shear zone a few millimetres to several centimetres thick. Compression in the toe zone of slides is low at sites where runout is possible, but in other locations causes emergent shears and complex folding. Failure histories are varied and range from simple unitary slides to complex sequential failures in which active-layer segments are mobilized progressively higher up the slope. This study demonstrates the importance of active-layer thermal and hydrological regimes, in addition to material properties, in determining the mode of slope failure.

Cultured human embryonic stem (hES) cells can acquire genetic and epigenetic changes that make them vulnerable to transformation. As hES cells with cancer-cell characteristics share properties with normal hES cells, such as self-renewal, teratoma formation and the expression of pluripotency markers, they may be misconstrued as superior hES cells with enhanced 'stemness'. We characterize two variant hES cell lines (v-hESC-1 and v-hESC-2) that express pluripotency markers at high levels and do not harbor chromosomal abnormalities by standard cytogenetic measures. We show that the two lines possess some features of neoplastic progression, including a high proliferative capacity, growth-factor independence, a 9- to 20-fold increase in frequency of tumor-initiating cells, niche independence and aberrant lineage specification, although they are not malignant. Array comparative genomic hybridization reveals an amplification at 20q11.1-11.2 in v-hESC-1 and a deletion at 5q34a-5q34b;5q3 and a mosaic gain of chromosome 12 in v-hESC-2. These results emphasize the need for functional characterization to distinguish partially transformed and normal hES cells.