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We discuss an approach to development of an associative memory model from the viewpoint of the theory of active perception. The theory of active perception allows one to develop the treebased memory model without the defects of the kd-tree and the vp-tree. Applications of the proposed model for solving problems of an image search by content from database are described. Also, we present the results of computer simulations directed at searching of similar and distorted images.

Neutron cross section standards are the basis for the determination of most neutron cross sections. They are used for both measurements and evaluations of neutron cross sections. Not many cross sections can be obtained absolutely – most cross sections are measured relative to the cross section standards and converted using evaluations of the standards. The previous complete evaluation of the neutron cross section standards was finished in 1987 and disseminated as the NEANDC/INDC and ENDF/B-VI standards. R-matrix model fits for the light elements and non-model least-squares fits for all the cross sections in the evaluation were the basis of the combined fits for all of the data. Some important reactions and constants are not standards, but they assist greatly in the determination of the standard cross sections and reduce their uncertainties – these data were also included in the combined fits. The largest experimental database used in the evaluation was prepared by Poenitz and included about 400 sets of experimental data with covariance matrices of uncertainties that account for all cross-energy, cross-reaction and cross-material correlations. For the evaluation GMA, a least-squares code developed by Poenitz, was used to fit all types of cross sections (absolute and shape), their ratios, spectrum-averaged cross sections and thermal constants in one full analysis. But, the uncertainties derived in this manner, and especially those obtained in the R-matrix model fits, have been judged to be too low and unrealistic. These uncertainties were substantially increased prior to their release in the recommended data files of 1987. Modified percentage uncertainties were reassigned by the United States Cross Section Evaluation Working Group's Standards Subcommittee for a wide range of energies, and no covariance (or correlation) matrices were supplied at that time. The need to re-evaluate the cross section standards is based on the appearance of a significant amount of precise experimental data and improved developments in the methodology of analysis and evaluation. Initial efforts to produce a new evaluation were made by the United States Cross Section Evaluation Working Group which formed a Task Force. It was realized that international cooperation would be needed to produce the evaluation. The Working Party on International Evaluation Cooperation of the Nuclear Energy Agency Nuclear Science Committee formed a Subgroup, and the International Atomic Energy Agency formed a Coordinated Research Project (CRP). These groups worked cooperatively to improve the evaluation process. The major effort in producing the evaluation was through the CRP. The evaluations of the neutron cross section standards were finalized in October 2005. Previous difficulties experienced with a data evaluation problem known as “Peelle's Pertinent Puzzle” create biases in the fit of correlated data, and they have been addressed to reduce this phenomenon. The new evaluations of the cross section standards also include covariance matrices of the uncertainties that contain fully justifiable values. The product of this international effort has been adopted as the neutron standards for ENDF/B-VII.0.

New measurements and an improved evaluation process were used to obtain a new evaluation of the neutron cross section standards. Efforts were made to include as much information as possible on the components of the data uncertainties that were then used to obtain the covariance matrices for the experimental data. Evaluations were produced from this process for the 6Li(n,t), 10B(n,α), 10B(n, α 1 γ ), 197Au(n,γ), 235U(n,f), and 238U(n,f) standard cross sections as well as the non-standard 6Li(n,n), 10B(n,n), 238U(n,γ) and 239Pu(n,f) cross sections. There is a general increase in the cross sections for most of the new evaluations, by as much as about 5%, compared with the ENDF/B-VI results. Covariance data were obtained for the 6Li(n,t), 6Li(n,n), 10B(n,α), 10B(n, α 1 γ ), 10B(n,n), 197Au(n,γ), 235U(n,f), 238U(n,f), 238U(n,γ) and 239Pu(n,f) reactions. Also an independent R-Matrix evaluation was produced for the H(n,n) standard cross-section, however, covariance data are not available for this reaction. The evaluations were used in the new ENDF/B-VII library.

This article represents the recommendations for the management of spontaneous intracerebral haemorrhage of the European Stroke Initiative (EUSI). These recommendations are endorsed by the 3 European societies which are represented in the EUSI: the European Stroke Council, the European Neurological Society and the European Federation of Neurological Societies.

The underestimation of the errors in the recommended neutron cross sections calculated on the basis of an analysis of measurement results using strict statistical methods is discussed. The basic reasons for the underestimation of the errors in the cross sections are described. A statistical model is proposed — a constant bias model — for taking into account effectively the component of the measurement error that is unknown to the experimentor. The results of a statistical analysis of the measurements of the ratio of the fission cross sections of 238U and 235U on the basis of the constant bias model are presented. It is noted that the experimental errors are much higher (on the average by a factor of 2) than the declared errors. The consequences of using the generally accepted method for correcting the errors in the evaluated cross sections are examined for an exactly solvable model example. It is shown that such a procedure does reconstruct the real errors in the evaluated cross sections.

To clarify the impairment of the GH/IGF-I axis in obstructive sleep apnea syndrome (OSAS), in 13 adult male patients with OSAS (OSA) as well as 15 weight-matched patients with simple obesity (OB) and 10 normal lean male subjects (NS), we studied: 1) the GH response to GHRH (1 micro g/kg iv) plus arginine (30 g iv); and 2) the IGF-I and IGF binding protein-3 responses to a very low dose recombinant human (rh)GH treatment (5.0 microg/kg sc per day for 4 d). The GH response to arginine plus GHRH in OSA was lower than in OB (P < 0.05), which in turn was lower than in NS (P < 0.001). Basal IGF-I levels in OSA were lower than in OB (P < 0.05), which in turn were lower than in NS (P < 0.03). As opposed to OB and NS, in OSA a very low rhGH dose did not affect IGF-I. Adjusting for age and basal values, rhGH-induced IGF-I rise in OSA was lower than in OB (P < 0.01). IGF binding protein-3, glucose, and insulin levels in the three groups were not modified by rhGH. OSA show a more marked impairment of the maximal secretory capacity of somatotroph cells together with reduced IGF-I sensitivity to rhGH stimulation. These findings suggest that OSAS is connoted by a concomitant impairment of GH secretion and sensitivity.

Investigations aimed at the development of neutron and proton cross-section evaluations for Th-232 at intermediate energies in the range of 0 to 200 MeV are described The coupled-channel optical mo ...

Investigations aimed at the development of neutron cross-section evaluations for U-238 at intermediate energies are briefly described. The coupled-channels optical model is used to calculate the ne ...

The problems due primarily to the limitations of modern computers, preventing adoption of modern methods for estimating neutron data in everyday practice and making it difficult to use the estimated data in applied programs, are discussed. Possible solutions of these problems are presented. Specifically, an identity transformation of the statistical functional to be minimized is found: this transformation makes it possible to avoid the construction, storage, and numerical inversion of superlarge covariation matrices of measurement uncertainties. The transformation makes it possible to perform statistical analysis of an arbitrarily large number of measurements.

Calculations of the isotopic composition, residual heat release, and helium content in mixed oxide fuel with a high americium content during a run and during prolonged cooldown were performed for a BOR-60 fast reactor as part of the preparation for the experimental program RETSIKL. The fuel composition consisted of 75% enriched uranium and 20 or 50% by mass of americium-curium fraction and rare-earth elements of spent VVER-1000 fuel (burnup 40 GW-daylton, 10 year holding period). The americium transmutation rate is about 16.5% for the reactor run, the mass of the accumulated curium is about 13% of the mass of the transmuted americium, the plutonium mass is 35–45% of the latter (almost all on the plutonium consists of nonfissioning isotopes). The total helium accumulation can reach 1 kg/ton of heavy metals. The residual heat release due to α decay242Cm in about 1 month is ∼1 MW/ton, which has important consequences for planned or emergency shutdown of a reactor. 1 figure, 5 tables, 3 references.

This work concerns the underestimation of the errors in the recommended neutron cross sections obtained by using strict statistical methods to analyze measurements. It is shown that one reason for this is inadequate representation of the initial experimental data, specifically, correlations of the experimental data are neglected. The effect of correlations of the experimental data on the error in the evaluated neutron cross sections is studied using realistic models and practical examples. Special attention is focussed on correlations of measurements performed by different authors. Analysis of correlations of this kind substantially increases the errors in the evaluated cross sections. Analysis of the model examples shows that the correction can be large (∼70%) even for cases with relatively weak correlation of the measurements performed by different authors. For the evaluated cross sections of the reactions103Rh(n, n′)103mRh and237Np(n, f) the corrections reach 41% and 25% for certain energy ranges. 5 figures, 1 table, 22 references.

Increase in blood pressure and its circadian alterations in Type 1 diabetes are usually associated with diabetic nephropathy. To evaluate if diabetes itself could be responsible for the observed increase in blood pressure levels, we studied a group of 17 normotensive, normoalbuminuric Type 1 diabetic patients with a disease duration more than 15 years, with no clinical evidence of autonomic neuropathy or ischaemic heart disease, and without any known determinant of hypertension, and a control group of 17 normal subjects, normotensive, each matched for sex, age, BMI, albumin excretion rate, and clinical blood pressure to a diabetic subject. In both groups an ambulatory blood pressure monitoring was performed through an oscillometric recorder. The mean systolic and diastolic ambulatory blood pressure values were significantly higher in diabetic patients (p < 0.001) in the 24-h analysis and during waking and sleeping periods. The night/day ratio of systolic and diastolic blood pressure were not significantly different in patients and controls, as well as heart rate values and heart rate variability. We conclude that mechanism(s) inherent to the diabetic condition other than diabetic nephropathy or autonomic neuropathy could be responsible for blood pressure evaluation in normotensive Type 1 diabetes with normoalbuminuria.

BACKGROUND: The surgical treatment for perforated peptic ulcer is still a matter of discussion. The surgeons, for many years, made their options between acid-reducing procedures with some morbi-mortality and simpler procedures like closure of the perforation. But, in these cases, were faced with a high chance of ulcer relapse. Since the proved link between peptic ulcer and gastroduodenal infection caused by H. pylori, a recommendation for a change in their attitudes going back to simpler procedures with eradication of the bacteria was done. AIM: To analyse ulcer recurrence in patients treated with the same surgical procedure but belonging to two different groups: positive and negative to H. pilori. METHODS: A total of 144 patients were treated with simple closure of their perforated pre-pyloric, pyloric and duodenal ulcers. Thirty days after operation they were submitted to upper endoscopy and tested for the bacteria by urease and histopathological exams and divided into two groups according to the results of the tests: positive and negative. The positive ones were eradicated and, together with the negative group, were followed through six months interval endoscopies and detection tests looking for ulcer relapses and reinfection in the eradicated group. The positive group consisted of 25 patients, with two patients considered non eradicable according to the treatment protocol. They were followed for an average period of 38,21 months. RESULTS: Relapse was detected in four patients (17,39%), half of them (8,69%) were reinfected. The negative group consisted of 26 patients, with a median follow-up of 38,28 months and eight (30,76%) relapses were detected. There was no statistical significant difference due probably to the high dropout of patients. CONCLUSION: Simple suture with H. pilori eradication is the gold standard for the positive group, leaving the question of acid-reducing procedures open for the negative ones. RACIONAL: O tratamento cirúrgico da úlcera péptica perfurada é assunto discutível. Os cirurgiões, por muitos anos, fizeram suas opções entre procedimentos de redução ácida, somente fechamento da perfuração - porém com maior chance de recidiva ulcerosa. Desde a comprovada vinculação da úlcera péptica e suas complicações à infecção gastroduodenal causada pelo Helicobacter pylori, houve recomendação para mudança na atitude dos cirurgiões na volta à operação mais simples com erradicação da bactéria. OBJETIVO: Analisar a recidiva ulcerosa em pacientes com úlcera perfurada H. pylori positiva que foram submetidos à simples sutura da lesão e omentopexia com erradicação da bactéria e compará-la com H. pylori negativo submetido ao mesmo tratamento cirúrgico. MÉTODOS: Cento e quatorze pacientes com úlceras pré-pilóricas, pilóricas e duodenais perfuradas foram atendidos com fechamento simples. Trinta dias após a operação submeteram-se à endoscopia digestiva alta com biópsias para testes da urease e histopatológicos. Foram divididos em dois grupos de acordo com o resultado dos testes: positivo e negativo.Os positivos foram erradicados e, junto com o grupo negativo, foram seguidos com endoscopias semestrais e testes de detecção para H. pylori procurando por recidiva ulcerosa e reinfecção no grupo erradicado. RESULTADOS: O grupo positivo foi formado por 25 pacientes, dos quais dois foram considerados não erradicáveis segundo os critérios do protocolo. Os demais foram seguidos por período médio de 38,21 meses e detectadas recidivas em quatro pacientes (17,39%), metade deles (8,69%) foram reinfectados. O grupo negativo foi formado por 26 pacientes, seguido por período médio de 38,28 meses e oito (30,76%) apresentaram recidiva ulcerosa. Não foi evidenciada diferença estatisticamente significativa entre os grupos. CONCLUSÃO: Em relação à recidiva ulcerosa, o fechamento simples seguido de erradicação da bactéria é o procedimento padrão para o grupo positivo; deixa-se em aberto a questão dos procedimentos ácido-redutores para o grupo negativo.

The existence of general measures for the covariance matrices of the evaluated data uncertainties obtained in different model and non-model least-squares fits of the same experimental data is considered. It is shown that some quantities (called measures here) calculated from the elements of covariance matrices are exactly and others are approximately conserved quantities independent from the model used in the fit. The use of these measures allows a simple comparison of uncertainties obtained in different evaluations of the same cross sections. The measures were used for the justification of the uncertainties of the neutron cross section standards evaluated in least-squares fits of a bulk volume of the experimental data. It is shown that the uncertainties obtained in the standards evaluation are realistic and determined completely by the uncertainties of the experimental data when taking into account all known correlations between the different experiments.

Background: Intracranial haemorrhage (ICH) is the type of stroke associated with the highest death rate, and about 30% of ICH occurs in patients on antithrombotic treatment. This study relates clinical presentations and outcome of ICH patients on oral anticoagulant (OA) or antiplatelet (AP) therapy admitted to 33 Italian emergency departments (ED). Methods: Consecutive patients were enrolled after cranial computed tomography (CT). Primary outcome was the Modified Rankin Scale (MRS) score at 3 months of follow-up. Common descriptive statistics were computed after stratification for traumatic or spontaneous ICH and identification of the anatomical location of bleeding. Multivariate logistic regression was used to assess predictors of death. Results: We recruited 434 patients on AP therapy and 232 on OA. There were 432 spontaneous and 234 traumatic ICH patients. The proportions of AP and OA patients undergoing neurosurgery were 21.8and 19.4%, respectively, while Conclusion: This study confirms the high prevalence of death or disability in OA and AP patients with ICH. As far as the determinants of mortality and disability are concerned, the results of this study might be useful in the clinical management and allocation of resources in the ED setting. The observed low use of procoagulant therapy highlights the need for ED educational programmes to heighten the awareness of available and effective haemostatic treatments.

Objective: To describe our experience with non-invasive ventilation (NIV) for patients with acute respiratory failure (ARF) in the emergency department (ED). Methods: A prospective/retrospective, observational study on 190 patients with ARF (mean ±SD age 72.2±12.9 years, mean APACHE II score 18.9±5.9), who received 200 NIV trials in an ED. We analysed the NIV register data (prospectively collected) and medical records (retrospective data abstraction) and evaluated clinical indications for NIV, patient outcomes, and predictive factors for success and death. NIV success was defined as tolerance of the procedure and no need for endotracheal intubation (ETI). Results: Main indications to NIV were cardiogenic pulmonary oedema (CPE) (70 trials), acute exacerbation of COPD (39), both CPE and acute exacerbation of COPD (11), pneumonia (48), decompensation of obesity/hypoventilation (6), other conditions (26). The procedure was successful in 60.5% of trials. Global mortality was 34.5%, similar to the APACHE II predicted mortality of 32%. ETI rates were 6.5% and tracheostomy rates 1%. The improvement of pH within six hours after NIV initiation was predictive of survival in the hypercapnic group. Conclusions: Our results confirm the global efficacy of NIV in an ED setting, and show that, in spite of lower success rate in "real practice" in comparison with RCTs, an intermediate care unit can represent an appropriate and less expensive setting to perform this technique. The low rate of ETI seems to be because of the high number of patients for whom NIV was used as "ceiling" treatment.

The main components of the high‐energy BROND library for actinides in the range up to 150 MeV are briefly discussed. The coupled‐channel optical model has been used to calculate the neutron total, elastic, and reaction cross sections. The parameters of the optical model have been determined on the basis of available experimental data including the recent precise measurements of the total cross sections for 232Th and 238U. Evaluations of fission cross sections, secondary neutron multiplicities and spectra, as well as charged‐particle production cross sections are performed in the frame of the statistical model that includes direct, preequilibrium, and equilibrium mechanisms of nuclear reactions. The Kalbach parameterization of angular distributions has been used to describe the double‐differential cross sections of emitted neutrons and charged particles in ENDF/B‐VI format.

A report is given of the progress achieved in an IAEA Co‐ordinated Research Project (CRP) to improve the cross‐section standards. The objectives of the CRP, started in 2002, were initially the understanding of the origin of the strong uncertainty reduction in R‐matrix model fits and the improvement of the evaluation methodology. These aims were extended in 2003 to the preparation of new evaluations for the standard 6Li(n,t), 10B(n,α), 10B(n,α1), 197Au(n,γ), 235U(n,f), and 238U(n,f) reactions. The methodology, codes, and experimental database developed by Poenitz and Hale for the ENDF/B‐VI standards evaluation were taken as the basis for the new evaluation. The major results achieved by the CRP participants include the testing and intercomparison of a number of codes that can be used in the standards evaluation, updating the database of experimental results, analysis of the reasons leading to the strong uncertainty reduction in model fits, and a study of the bias in evaluated data caused by the Peelles’s Pertinent Puzzle (PPP) effect, which has been widely discussed in the nuclear data community since the ENDF/B‐VI standards evaluation was completed. Preliminary results of the new standards evaluation are shown. The use of the new 235U(n,f) cross section leads to better consistency in calculations of some important integral experiments.

In Italy departments of emergency medicine and emergency medical service systems (EMS) were first set up at the end of the 1970s. Since that time many dramatic and significant changes have taken place in the care of the critically ill patient. In Italy the interest in emergency problems and the need for emergency intervention have increased considerably. Nevertheless several problems still have to be solved in order to obtain a standardized organization of the emergency system in Italy and uniform training of emergency care providers.

Work is reported here on the process and present results of an international evaluation of the neutron cross section standards. The evaluations include the H(n,n), 3He(n,p), 6Li(n,t), 10B(n,α), 10B(n,α1γ), 197Au(n,γ), 235U(n,f), and 238U(n,f) standard reactions as well as the 238U(n,γ) and 239Pu(n,f) reactions. This evaluation was performed to include new experiments on the standards that have been made since the ENDF/B-VI evaluation was completed and to improve the evaluation process. Evaluations have been completed for the 6Li(n,t), 197Au(n,γ) and 238U(n,γ) cross sections. Also below 20 MeV the H(n,n), 235U(n,f), 238U(n,f) and 239Pu(n,f) cross sections are completed. Many of the cross sections being evaluated are used in neutron dosimetry for fluence determination. The general trend observed for the evaluations is an increase in the cross sections for most of the reactions from fractions of a percent to several percent compared with the ENDF/B-VI results.

The use of hypnotics for sleep disturbances has been discouraged for patients with severe chronic obstructive pulmonary disease (COPD), because of potential adverse effects on ventilation. We evaluated the clinical impaction of benzodiazepine use in patients presenting to the Emergency Department (ED) with acute exacerbation of COPD.

In Italy departments of emergency medicine and emergency medical service systems (EMS) were first set up at the end of the 1970s. Since that time many dramatic and significant changes have taken place in the care of the critically ill patient. In Italy the interest in emergency problems and the need for emergency intervention have increased considerably. Nevertheless several problems still have to be solved in order to obtain a standardized organization of the emergency system in Italy and uniform training of emergency care providers.

Rational functions are applied to two concrete problems of neutron-physics calculations: obtaining group constants in the resonance energy region and including the Doppler effect in the resonance analysis of neutron cross sections. Tables show the results of processing a model problem incorporating the Doppler effect. The results of the paper support, on the basis of new data, the general conclusion made previously: Pade approximation is a natural and convenient method of describing neutron data, primarily in the resonance region, and this representation can be applied at all stages: from the processing of the initial information to use in reactor calculations.

The method presented above for constructing rational approximants and obtaining their statistical characteristics is fairly convenient and universal. When it is considered that exponential-harmonic analysis also reduces to rational approximation, not of the function itself but of the application of the Fourier and Laplace transforms to the function [15a, b], the range of application of this method encompasses practically all the major systems of approximating functions. The existence of pole singularities in the Pade approximant is an extremely valuable analytic property, substantially expanding the region of convergence and increasing its speed as compared with the polynomial approximation. The Pade approximation is particularly a natural instrument for processing resonance curves since the resonances correspond to complex poles of the approximant. But in the general case as well analytic representation of data in this form is convenient and compact. Thus, representation of data on the cross sections for threshold reactions under the action of neutrons (BOSPOR library [14h]) in the form of rational functions resulted in a 20-fold reduction of the numerical information subject to storage as compared with the pint-by-point assignment with the same accuracy of description. All of this enables the Pade approximation to be considered as a promising method of representing neutron and nuclear data.

This work is an attempt to find an answer to the question: once arrived at the diagnostic identification of a certain type of idiopathic headache, which treatment should be followed? On the basis of recent researches and experience acquired during ten years' activity of our Headache Unit, a diagnostic identification can be made for migraine (in all its types and evolution stages), cluster headache, tension headache and pure psycogenic headache. Among the most widely used drugs, positive pharmacological results were obtained with: cyproheptadine, pizotifen, cinnarizine, lysergic acid derivatives, histamine, reserpine, clonidine and a barbituric acid derivative. The therapeutic cycles were standardized, for each drug, in the way of administration, dosage and total duration of the treatment. A comparison between the data obtained and the pre-therapeutic situation was made. When repeated, the most efficacious therapeutic cycle was evaluated. According to Pearson's dispersion index, each group of patients improved respresents 16.68% of the expected total results (frequency of attacks reduced to 50%, 25% and 0%): for cyproheptadine, pizotifen, methysergide, histamine, clonidine and allil-propyl-malonylurea, the "p" is less than 0.001; for cinnarizine, less than 0.02. This "a posteriori" analysis does not take into account the placebo control, the "anticipation effect", and the "carry over effect". It cannot therefore be a comparison of efficacy among the various drugs. An evaluation based on "among patients" and "inside patient" method by means of the cross over system, can instead give some useful suggestion about which treatment is to be recommended to patients suffering from recurrent headaches. With regard to migraine sufferers: cinnarizine, cyproheptadine, clonidine, histamine, pizotifen und reserpine. For cluster headaches: cinnarizine, cyproheptadine, clonidine, histamine and reserpine. For tension headaches: cyproheptadine. For pure psychogenic headache: allyl-propyl-malonylurea. For migraine attacks or parossystic crises in the course of ondulating or continuous headaches, positive therapeutic results, statistically significant, were obtained with an association of indomethacin, caffeine and prochlorperazine.