EQUILIBRIUM CALCULATION IN THE SYSTEM: URANYL NITRATE, NITRIC ACID, WATER, TBP, AND KEROSENE DILUENT USING THE ORACLE DIGITAL COMPUTER

A set of equations was written which allowed the calculation of equilibrium concentrations in the solvent phase of nitric acid and uranyl nitrate, given the initial TBP concentration in the solvent and the aqueous phase concentrations of acid and uranium. An ORACLE subroutine was written based on these equations which will calculate a set of equilibrium values in about 35 milliseconds. The subroutine was incorporated into a short program to calculate equilibrium points. A set of calculated points are presented in graphical form for 5, up to 7 M and uranyl nitrate concentrations up to 0.6 M in the aqueous phase. Since these calculations were based on limited data, it is the purpose of this memo to invite comment on their accuracy. The equations were reworked from a Russian paper by A. M. Rozen and L. P. Khorkhorina, using emperical polynomial fits for some poorly defined parameters, and were based principally on data from J. W. Codding. This project was undertaken to provide a subroutine to calculate equilibria in a general purpose ORACLE program to calculate the performance of multi-stage compound extraction cascades with more than one significant solute. (auth

AER Building Blocks for Multi-Layer Multi-Chip Neuromorphic Vision Systems

A 5-layer neuromorphic vision processor whose components communicate spike events asychronously using the address-eventrepresentation (AER) is demonstrated. The system includes a retina chip, two convolution chips, a 2D winner-take-all chip, a delay line chip, a learning classifier chip, and a set of PCBs for computer interfacing and address space remappings. The components use a mixture of analog and digital computation and will learn to classify trajectories of a moving object. A complete experimental setup and measurements results are shown.Unión Europea IST-2001-34124 (CAVIAR)Ministerio de Ciencia y Tecnología TIC-2003-08164-C0

Characteristics associated with quality of life among people with drug-resistant epilepsy

Quality of Life (QoL) is the preferred outcome in non-pharmacological trials, but there is little UK population evidence of QoL in epilepsy. In advance of evaluating an epilepsy self-management course we aimed to describe, among UK participants, what clinical and psycho-social characteristics are associated with QoL. We recruited 404 adults attending specialist clinics, with at least two seizures in the prior year and measured their self-reported seizure frequency, co-morbidity, psychological distress, social characteristics, including self-mastery and stigma, and epilepsy-specific QoL (QOLIE-31-P). Mean age was 42 years, 54% were female, and 75% white. Median time since diagnosis was 18 years, and 69% experienced ≥10 seizures in the prior year. Nearly half (46%) reported additional medical or psychiatric conditions, 54% reported current anxiety and 28% reported current depression symptoms at borderline or case level, with 63% reporting felt stigma. While a maximum QOLIE-31-P score is 100, participants’ mean score was 66, with a wide range (25–99). In order of large to small magnitude: depression, low self-mastery, anxiety, felt stigma, a history of medical and psychiatric comorbidity, low self-reported medication adherence, and greater seizure frequency were associated with low QOLIE-31-P scores. Despite specialist care, UK people with epilepsy and persistent seizures experience low QoL. If QoL is the main outcome in epilepsy trials, developing and evaluating ways to reduce psychological and social disadvantage are likely to be of primary importance. Educational courses may not change QoL, but be one component supporting self-management for people with long-term conditions, like epilepsy

Arctic quaternary ostracods and their use in paleoreconstructions

The paper deals with original and published data on fossil ostracodal assemblages from the Eurasian Arctic Kara, Laptev and Chuckchi seas. As a whole, six ecologically different assemblages were distinguished (freshwater, brackish water, marine of the inner, middle and outer shelves and upper continental slope), they replace each other upcore reflecting a gradual increase in water depth and distance from the coast. These assemblages are stable in the entire Arctic region and can be used for interpretation of environments in different Arctic areas

Erythropoietic protoporphyria

Erythropoietic protoporphyria (EPP) is an inherited disorder of the haem metabolic pathway characterised by accumulation of protoporphyrin in blood, erythrocytes and tissues, and cutaneous manifestations of photosensitivity. EPP has been reported worldwide, with prevalence between 1:75,000 and 1:200,000. It usually manifests in early infancy upon the first sun exposures. EPP is characterised by cutaneous manifestations of acute painful photosensitivity with erythema and oedema, sometimes with petechiae, together with stinging and burning sensations upon exposure to sunlight, without blisters. These episodes have a variable severity depending on the exposure duration and may result in chronic permanent lesions on exposed skin. As protoporphyrin is a lipophilic molecule that is excreted by the liver, EPP patients are at risk of cholelithiasis with obstructive episodes, and chronic liver disease that might evolve to rapid acute liver failure. In most patients, EPP results from a partial deficiency of the last enzyme of the haem biosynthetic pathway, ferrochelatase, EC 4.99.1.1/FECH (encoded by the FECH gene). EPP appears to be inherited as an autosomal dominant disease, the clinical expression of which is modulated by the presence of the hypomorphic FECH IVS3-48C allele trans, but recessive inheritance with two mutated FECH alleles has also been described. In about 2% of patients, overt disease was recently shown to be caused by gain-of-function mutations in the erythroid-specific aminolevulinic acid synthase 2 (ALAS2/ALAS, EC 2.3.1.27) gene and named X-linked dominant protoporphyria. Diagnosis is established by finding increased levels of protoporphyrin in plasma and red blood cells, and detection of a plasma fluorescence peak at 634 nm. Investigations for hepatic involvement, ferrochelatase activity level, genetic analysis (FECH mutations, presence of the hypomorphic FECH IVS3-48C allele trans and ALAS2 mutations) and family studies are advisable. Differential diagnosis includes phototoxic drug reactions, hydroa vacciniforme, solar urticaria, contact dermatitis, angio-oedema and, in some cases, other types of porphyria. Management includes avoidance of exposure to light, reduction of protoporphyrin levels and prevention of progression of possible liver disease to liver failure. As the major risk in EPP patients is liver disease, a regular follow-up of hepatic involvement is essential. Sequential hepatic and bone marrow transplantation should be considered as a suitable treatment for most severe cases of EPP with hepatic involvement. EPP is a lifelong disorder whose prognosis depends on the evolution of the hepatic disease. However, photosensitivity may have a significant impact on quality of life of EPP patients

An overview of the cutaneous porphyrias

This is an overview of the cutaneous porphyrias. It is a narrative review based on the published literature and my personal experience; it is not based on a formal systematic search of the literature. The cutaneous porphyrias are a diverse group of conditions due to inherited or acquired enzyme defects in the porphyrin–haem biosynthetic pathway. All the cutaneous porphyrias can have (either as a consequence of the porphyria or as part of the cause of the porphyria) involvement of other organs as well as the skin. The single commonest cutaneous porphyria in most parts of the world is acquired porphyria cutanea tarda, which is usually due to chronic liver disease and liver iron overload. The next most common cutaneous porphyria, erythropoietic protoporphyria, is an inherited disorder in which the accumulation of bile-excreted protoporphyrin can cause gallstones and, rarely, liver disease. Some of the porphyrias that cause blistering (usually bullae) and fragility (clinically and histologically identical to porphyria cutanea tarda) can also be associated with acute neurovisceral porphyria attacks, particularly variegate porphyria and hereditary coproporphyria. Management of porphyria cutanea tarda mainly consists of visible-light photoprotection measures while awaiting the effects of treating the underlying liver disease (if possible) and treatments to reduce serum iron and porphyrin levels. In erythropoietic protoporphyria, the underlying cause can be resolved only with a bone marrow transplant (which is rarely justifiable in this condition), so management consists particularly of visible-light photoprotection and, in some countries, narrowband ultraviolet B phototherapy. Afamelanotide is a promising and newly available treatment for erythropoietic protoporphyria and has been approved in Europe since 2014

Key Terms and Definitions in Acute Porphyrias: Results of an International Delphi Consensus Led by the European Porphyria Network

Background: Acute porphyrias are a group of rare inherited disorders causing acute neurovisceral attacks. Many terms used frequently in the literature and in clinical practice are ambiguous, which can lead to confusion in the way patients are managed, studied, and reported in clinical studies. Agreed definitions are a necessary first step in developing management guidelines and will facilitate communication of results of future clinical research. Methods: The Delphi method was used to generate consensus on key terms and definitions in acute porphyria. The process started with a brainstorming phase offered to all members of the European Porphyria Network followed by 2 Delphi rounds among international experts in the field of porphyria (the Acute Porphyria Expert Panel). A consensus of 75% or more was defined as the agreement threshold. Results: 63 respondents from 26 countries participated in the brainstorming phase, leading to the choice of 9 terms and definitions. 34 experts were invited to take part in the Delphi rounds. 7 of the initial 9 terms and definitions which entered the first Delphi round achieved the threshold for agreement. Following a second Delphi round, all 9 definitions achieved agreement. Conclusion: Agreement on the definitions for 9 important terms describing acute porphyrias represents a significant step forward for the porphyria community. It will facilitate more accurate comparison of outcomes among porphyria centres and in clinical trials and provide a strong framework for developing evidence based clinical guidelines.Background: Acute porphyrias are a group of rare inherited disorders causing acute neurovisceral attacks. Many terms used frequently in the literature and in clinical practice are ambiguous, which can lead to confusion in the way patients are managed, studied, and reported in clinical studies. Agreed definitions are a necessary first step in developing management guidelines and will facilitate communication of results of future clinical research. Methods: The Delphi method was used to generate consensus on key terms and definitions in acute porphyria. The process started with a brainstorming phase offered to all members of the European Porphyria Network followed by 2 Delphi rounds among international experts in the field of porphyria (the Acute Porphyria Expert Panel). A consensus of 75% or more was defined as the agreement threshold. Results: 63 respondents from 26 countries participated in the brainstorming phase, leading to the choice of 9 terms and definitions. 34 experts were invited to take part in the Delphi rounds. 7 of the initial 9 terms and definitions which entered the first Delphi round achieved the threshold for agreement. Following a second Delphi round, all 9 definitions achieved agreement. Conclusion: Agreement on the definitions for 9 important terms describing acute porphyrias represents a significant step forward for the porphyria community. It will facilitate more accurate comparison of outcomes among porphyria centres and in clinical trials and provide a strong framework for developing evidence based clinical guidelines