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Giant volcanic eruptions have the potential to overturn civilizations. Yet, the driving mechanism and timescale over which batholithic magma reservoirs transition from non‐eruptible crystal mush to mobile melt‐dominated stages and our capacity to detect a pending super‐eruption remain obscure. Here we show, using Sr isotope zonation in plagioclase crystals from three Andean large‐magnitude eruptions (Atana, Toconao, and Tara ignimbrites), that eruptible magma forms by amalgamation of isotopically diverse crystal populations and silicic melt without large‐scale reheating. In each case, crystals record large isotopic diversity in crystal cores, converging toward a common value in crystal rims that coincides with the composition of the rhyolitic carrier melt. Using diffusion chronometry, we show that the assembled magma resided pre‐eruptively in the crust for timescales of no more than decades to centuries for Atana and Tara, but up to several millennia for Toconao. These timescales and isotopic observations are consistent with the accumulation and destabilization of melt‐rich layers in crystal mush. While the prospect of capturing such melt lenses with most geophysical monitoring techniques is pessimistic, gravity modeling indicates that such structures are potentially resolvable. Our findings provoke a new assessment of the origin and hazards associated with large magnitude explosive eruptions. Plain Language Summary: Super‐eruptions are the largest manifestation of explosive volcanism on Earth. If such an event would occur today, it could deeply impact human civilization on a global scale. Yet, signals that may emerge prior to such eruptions are difficult to constrain. To gain greater understanding of the mechanisms and timescales over which giant, eruptible, reservoirs form, and to evaluate our capacity of capturing the evolution toward large eruptions, we studied plagioclase crystals, a mineral that is an excellent recorder of magmatic processes. For three large eruptions in the Central Andes, we analyzed strontium isotopes in traverses from crystal cores to rims to provide a temporal record of melt composition. Our results show that, in each case, the eruptible magma amalgamated from distinct pre‐existing magma pockets that merged prior to eruption. This merged state of the magma did not exist for longer than a few hundred to thousands of years based on the preservation of the crystal strontium‐isotope traverses at high temperatures. These results are consistent with the destabilization of melt‐rich layers on timescales comparable to human lifespans. Although most geophysical imaging methods are unlikely to capture this process, our calculations indicate that gravity monitoring of super‐volcanoes can potentially resolve such structures. Key Points: Sr‐isotopes in plagioclase record the emergence of eruptible magma through amalgamation of pre‐existing mush in the Central AndesThe amalgamated magma did not reside at depth for longer than centuries to millennia based on diffusion chronometryForward modeling indicates that high‐precision gravity monitoring has large potential to resolve eruptible magma amalgamation [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Vitamin B12 is found almost exclusively in animal‐based foods and is therefore a nutrient of potential concern for those following a vegetarian or vegan diet. Vegans, and anyone who significantly limits intake of animal‐based foods, require vitamin B12‐fortified foods or supplements.Vitamin B12 deficiency has several stages and may be present even if a person does not have anaemia. Anyone following a vegan or vegetarian diet should have their vitamin B12 status regularly assessed to identify a potential problem.A useful process for assessing vitamin B12 status in clinical practice is the combination of taking a diet history, testing serum vitamin B12 level and testing homocysteine, holotranscobalamin II or methylmalonic acid serum levels.Pregnant and lactating vegan or vegetarian women should ensure an adequate intake of vitamin B12 to provide for their developing baby.In people who can absorb vitamin B12, small amounts (in line with the recommended dietary intake) and frequent (daily) doses appear to be more effective than infrequent large doses, including intramuscular injections.Fortification of a wider range of foods products with vitamin B12, particularly foods commonly consumed by vegetarians, is likely to be beneficial, and the feasibility of this should be explored by relevant food authorities. [ABSTRACT FROM AUTHOR]

The various superstructure phases that occur with the anion-deficient compositions of binary oxides MO2 − x with the fluorite structure as parent are explored here in terms of the original `coordination defect' (or CD) concept in which each vacant oxygen site, □, is `coordinated' by six O atoms thereby creating the octahedral `structure-determining' entity [ M3.5□O6]. It emerges that the structure and composition of each anion-deficient (polymorph) phase can be described in terms of crystallographic `motifs' which comprise sets of parallel coplanar polygons based on ½〈210〉F and ½〈111〉F CD linkages. [ABSTRACT FROM AUTHOR]

The article discusses the importance of Vitamin B 12 to those following a vegetarian or vegan diet. Factors that may contribute to Vitamin B 12 deficiency include loss of intrinsic factor, gastric acid or other protein-digesting enzymes. A simple diet history can be used as an indicator of Vitamin B 12 intake and adequacy. The need of pregnant or breastfeeding vegan and vegetarian women to consume a reliable source of Vitamin B 12 is cited.

Summary. Defective hemostasis in haemophilia patients with FVIII inhibitors results in a dramatic decrease in thrombin generation forming unstable fibrin clots that are susceptible to fibrinolyisis. In this study we tested whether the combination of plasma derived activated prothrombin complex concentrate (pd-aPCC) with tranexamic acid (TXA) may improve fibrin clot stability in FVIII inhibitor plasma. A microplate assay for clot lysis time was used to assess clot stability in FVIII inhibitor plasma. The effect of pd-aPCC on clot stability was first tested using the commercial FVIII inhibitor plasma. TXA (5 ∼ 10 mg mL−1) increased clot lysis time, but pd-aPCC (0.25 ∼ 1.0 U mL−1) had no effect on it. The combination of pd-aPCC and TXA significantly increased clot lysis time compared with TXA alone. The effect appeared to be limited to fibrin clot resistance to fibrinolysis, as TXA was found to have no effect on thrombin generation induced by pd-aPCC. The effect of pd-aPCC and TXA on clot stability was then tested and verified in plasma samples from ten patients with severe haemophilia A and inhibitors. The combination of TXA (10 mg mL−1) and pd-aPCC (0.5 U mL−1) significantly increased clot lysis time compared to TXA alone. Our results suggest that the combination of pd-aPCC with TXA improves clot stability in FVIII inhibitor plasma without additional increases in thrombin generation. [ABSTRACT FROM AUTHOR]

The crystallographic, group and subgroup relationships are explored for mixed transition metal nitrides of the type: Li7MVN4. The hypothetical parent MgN4 should have the anti-fluorite structure with the space group Fm3m. However, the corresponding mixed-cation nitride [Li7V]N4 is actually tri-morphic comprising one tetragonal phase SO: P42Jnmc (c) and two cubic phases with space groups: Pa3(β) and P43n(γ), respectively. These three polymorphs are clearly subgroups arising from lowering of symmetry of the parent space group, Fm3rn. Further decomposition of the pathways (or Bärnighausen Trees) reveals a rich variety of compounds derived from the subgroups and supergroups of the anti-fluorite parent structure. The most important outcome is that all the structures analysed in this work, which derive from the parent Fm3m space group of fluorite, can be identified as partial substructures in the three phases of Li7VN4. All these substructures can be rationalized as pseudo-compounds by assuming the appropriate electron transfer between the atoms forming the nitride, following the extended Zintl-Klemm concept (EZKC) that implies charge transfer between atoms, even if they are of the same kind. [ABSTRACT FROM AUTHOR]

Thrombotic thrombocytopenic purpura (TTP) may be idiopathic or secondary. We report seven TTP cases precipitated by pancreatitis. The patients were admitted with acute pancreatitis and at that time had no clinical or laboratory features of TTP. The median time to develop TTP after pancreatitis was 3 d. The patients had moderately reduced ADAMTS13 activity (mean activity 49%; normal range 66–126%) with no evidence of anti-ADAMTS13 inhibitory autoantibodies. The median number of plasma exchanges to remission was 10 (range 7–14) and no additional treatment with immunosuppression was required to maintain remission. There have been no relapses to date. [ABSTRACT FROM AUTHOR]

We consider the problem of locating a mobile object (user) in the cellular communication system on the basis of the triangulation method and the Gaussian multipath-channel model under urban conditions of signal propagation. The probability density function of the maximum likelihood estimate of Cartesian coordinates of the user is found if two or three base stations arbitrarily located with respect to one another are used. It is shown that the user-locating error depends on the distance between the base stations, mutual location of the user and the base stations, and the variance of the user-bearing estimation error for each base station. In this case, using the third base station significantly improves the user-locating accuracy. [ABSTRACT FROM AUTHOR]

Mechanical heart valves are associated with a risk of thromboembolism and anticoagulation is generally recommended. However, this is inevitably associated with a risk of intracranial bleeding. The case of a patient who sustained an intracranial bleed while taking warfarin for a prosthetic aortic valve and a further two intracranial bleeds while on heparin as an inpatient is discussed and the literature on the management of intracranial haemorrhage in patients on warfarin with prosthetic valves is reviewed. [ABSTRACT FROM AUTHOR]

The article presents a study on the prevalence of thrombophilia and hyperhomocysteinaemia in patients suffering symptomatic peripheral vascular disease. The researchers applied comprehensive screening procedures and fasting homocysteine assays to 150 patients. They noted that a quarter of patients had thrombophilia and a third had hyperhomocysteinaemia.

First-feeding Arctic char Salvelinus alpinus were subjected to two different photoperiods (light conditions at latitude 43°28′N [normal] and 24 h of continuous light) and two different feeding schedules (fed only during the natural photoperiod [normal] and 24-h continuous feeding) for 12 weeks. Arctic char subjected to 24 h of continuous light and continuous feed availability had a significantly lower cumulative mortality (P < 0.05) and higher mean final weights (P < 0.05) without an accompanying increase in within-treatment variability compared with fish raised in either ambient photoperiods or under restricted feeding regimens. These results indicate potential commercial benefits associated with extended photoperiod and feeding regimens for the culture of juvenile Arctic char. [ABSTRACT FROM AUTHOR]

Epidemiology data on multiple myeloma (MM) occurrence and outcome is inconsistent whilst a major limitation of randomized controlled trials is selection bias. We present a population-based analysis of patients diagnosed with MM in the South Thames area, which comprises 5·4 million adult inhabitants. A total of 855 cases of MM were ascertained between 1999 and 2000 in a collaborative project involving haematologists and the Thames Cancer Registry. The age-standardized rate was 3·29 per 100 000 and 4·82 cases per 100 000 (World Standard and European Population respectively). The median age was 73 years. The median survival for the whole group was 24 months whist it was 42 and 18 months in those aged less than 65 years and greater than 65 years respectively (P < 0·001). This population study has shown a higher incidence than previously reported in the UK and Europe and provides a benchmark for future studies. If survival is to be improved, future clinical trials and health care planning should consider patients over 65 years of age. [ABSTRACT FROM AUTHOR]

We carry out a comparative analysis of performances of a cellular communication system with adaptive modulation and coding (AMC) and a system with power control (PC). It is shown that the performance of an AMC system is higher than the performance of a PC system for an arbitrary probability density function of the signal fading. To achieve identical throughputs of the two systems, the mean transmitted power for PC must be greater than that for AMC. For identical mean transmitted powers, the throughput of an AMC system is always greater than that of a PC system. We consider code division multiple-access (CDMA) systems with arbitrary numbers of fading time-taps (paths), having a statistically independent Rayleigh fading of signals from path to path. The influence of self-interference on AMC and PC performance is studied. This self-interference results from the nonideal path separation in the receiver. [ABSTRACT FROM AUTHOR]

We describe 21 patients with severe and life-threatening autoimmune cytopenias resistant to standard immunosuppression who were treated with the monoclonal antibody Campath-1H. Four patients had autoimmune neutropenia, four had autoimmune haemolytic anaemia, four had pure red cell aplasia, one had immune thrombocytopenia purpura (ITP), three had autoimmune haemolytic anaemia and ITP (Evan's syndrome), three had autoimmune pancytopenia (ITP, autoimmune neutropenia and autoimmune haemolytic anaemia), one had ITP (associated with acquired Glanzmann's disease) and autoimmune neutropenia, and one had ITP and red cell aplasia. Campath-1H was administered at a dose of 10 mg/d as an intravenous infusion for 10 d. Responses were seen in 15 patients, which were sustained in six. Relapse occurred in eight patients after Campath-1H treatment. Patients entering the study later, received cyclosporine after Campath-1H in an attempt to reduce the incidence of relapse. Three patients received a second course of Campath-1H; all responded but later relapsed. Fourteen patients are alive at a median of 12 months (range 4–61) after Campath-1H. Campath-1H represents an alternative therapeutic option for severe, refractory autoimmune cytopenias. [ABSTRACT FROM AUTHOR]

The pharmacokinetic behaviour and neuromuscular blockade produced by the administration of fazadinium bromide at a dose of 1 mg/kg have been studied in seven patients with end-stage renal failure. No significant differences were found in the pharmacokinetic or pharmacodynamic properties when compared with patients with normal renal function. It is suggested that fazadinium may be superior to either d-tubocurarine or pancuronium in providing muscle relaxation for patients with renal failure. [ABSTRACT FROM AUTHOR]

Presents letters to the editor related to dermatology. Information on linear skin diseases; Comment on the spontaneous bruising during treatment with isotretinoin; Description of the disease Klippel-Trenaunay syndrome.

Rat T-cell populations were analysed for their surface expression of CD4, CD8 and class II MHC antigens using monoclonal antibodies (McAbs) W3/25, Ox8 and Ox6 in immunofluorescence and immunoenzyme cytochemistry. Resting T cells expressed either CD4 (W3/25) or CD8 (Ox8) molecules, but not both, and did not express class II MHC antigens. In contrast, when purified T cells were stimulated by Con A or by alloantigens in a mixed lymphocyte reaction (MLR), over 60% of the cells expressed class II MHC antigens after 48-72 hr. The expression of class II MHC antigens by the T-cell blasts was transient and no longer evident after 96 hr of activation. In addition, T cells activated by either alloantigen or lectin expressed CD4 (W3/25) and CD8 (Ox8) molecules simultaneously: 30% of cells activated in MLR and 50% of Con A-activated cells expressed both markers within 48 hr of activation. The overlapping of the CD4- and CD8-positive subpopulations within the T-cell population was inferred from the results of staining for each marker separately and confirmed using a double-immunoenzyme staining method. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)