Next generation gamma-ray Cherenkov detectors for the National Ignition Facility.

The newest generation of Gas Cherenkov Detector (GCD-3) employed in Inertial Confinement Fusion experiments at the Omega Laser Facility has provided improved performance over previous generations. Comparison of reaction histories measured using two different deuterium-tritium fusion products, namely gamma rays using GCD and neutrons using Neutron Temporal Diagnostic (NTD), have provided added credibility to both techniques. GCD-3 is now being brought to the National Ignition Facility (NIF) to supplement the existing Gamma Reaction History (GRH-6m) located 6 m from target chamber center (TCC). Initially it will be located in a reentrant well located 3.9 m from TCC. Data from GCD-3 will inform the design of a heavily-shielded "Super" GCD to be located as close as 20 cm from TCC. It will also provide a test-bed for faster optical detectors, potentially lowering the temporal resolution from the current ∼100 ps state-of-the-art photomultiplier tubes (PMT) to ∼10 ps Pulse Dilation PMT technology currently under development.

Design and fabrication of a window for the gas Cherenkov detector 3.

The gas Cherenkov detector 3 was designed at Los Alamos National Laboratory for use in inertial confinement fusion experiments at both the Omega Laser Facility and the National Ignition Facility. This instrument uses a low-Z gamma-to-electron convertor plate and high pressure gas to convert MeV gammas into UV/visible Cherenkov photons for fast optical detection. This is a follow-on diagnostic from previous versions, with two notable differences: the pressure of the gas is four times higher, and it allows the use of fluorinated gas, requiring metal seals. These changes force significant changes in the window component, having a unique set of requirements and footprint limitations. The selected solution for this component, a sapphire window brazed into a stainless steel flange housing, is described.

[Guidelines for the clinical management of neuropathic pain (II)]. / Guías de práctica clínica del dolor neuropático (II).

INTRODUCTION: Up to 5% of the population suffers from neuropathic pain (NP). A bibliographical search in several databases revealed that, to date, there are no protocols to guide physicians who are not specialists in pain that enable them to treat NP and thus improve patients' quality of life. AIMS: The aim of this study is to provide Spanish-speaking physicians who are not specialists in pain with a set of guidelines for the treatment of NP. A bibliographical search was performed in order to base the results and conclusions on the evidence-based medicine methodology. DEVELOPMENT: First, we review the most effective clinical and paraclinical methods for diagnosing NP, and the LANSS pain scale is reported as the most appropriate method of clinically evaluating NP. The anatomical paths and the physiology of pain are then described and we review the molecular variables involved. Finally, we point out the current therapeutic options and propose an algorithm for the treatment of NP. CONCLUSIONS: There is no specific set of guidelines for the treatment of NP. At the present time, the keystone of NP treatment consists in the use of antidepressant and anticonvulsive drugs. There is a need for further clinical trials to prove the effectiveness of using combined medication.

[Guidelines for the clinical management of neuropathic pain (I). Protocol]. / Guías de práctica clínica del dolor neuropático (I). Protocolo.

AIMS: The aim of this study is to develop a set of guidelines for the clinical management of neuropathic pain (NP), a disorder suffered by up to 5% of the population, specifically for use by the Spanish-speaking community, in order to improve the quality of medical care and to standardise the treatments offered in medical centres. DEVELOPMENT: The paper describes the methodology used to search for guidelines concerning the clinical management of NP in databases, written communications and other resources, and the results of this search are presented. The research group is split into three groups: anatomical-physiological, diagnosis and therapeutic approach, each of which defines the nature of the papers that used to design the protocol.

Consistent canonical quantization of general relativity in the space of vassiliev invariants

We present a quantization of the Hamiltonian and diffeomorphism constraint of canonical quantum gravity in the spin network representation. The novelty consists in considering a space of wave functions based on the Vassiliev invariants. The constraints are finite, well defined, and reproduce at the level of quantum commutators the Poisson algebra of constraints of the classical theory. A similar construction can be carried out in 2+1 dimensions leading to the correct quantum theory.

A convergent validity study of Cloninger's Temperament and Character Inventory with the Coolidge Axis II Inventory.

This study examined the convergent validity of the Temperament and Character Inventory (TCI), a measure of four biosocial temperaments and three character dimensions with the Coolidge Axis II Inventory (CATI), a measure of 14 personality disorders. A nonclinical sample of 163 college students was given both measures, and the data were analyzed with bivariate and multivariate statistics. Hypotheses generated from the findings of Svrakic, Whitehead, Przybeck, and Cloninger (1993, Archives of General Psychiatry, 50, 991-999) were confirmed for a majority of the relationships between the two measures. The preliminary results provide qualified support for the TCI and Cloninger's biosocial theory in the assessment of personality disorders.

Olfactory neuroblastoma: a case report.

A neuroblastoma arising in the nasal cavity of a 66-year-old male invaded the frontal sinus and extended into the cranial cavity. Light microscopy revealed sheets of small ovoid cells and many small glands bordered by columnar cells which were strongly immunoreactive to epithelial markers. Focal reactivity for synaptophysin and chromogranin was seen within the sheets of small cells. Electron microscopy confirmed the presence of olfactory differentiation.

The effects of interference on verbal learning in multiple sclerosis.

Thirty multiple sclerosis (MS) patients were compared with 30 matched (age and education) controls and were asked to learn and recall 20 target words that were placed among 24 distracter words. Targets and distracters were printed on different colored cards, and the subjects were asked to read each word aloud and recall the target words. This task was repeated four times. The MS patients recalled significantly fewer words across the four trials. A second list without distracters was presented for two trials, and there were no significant differences between the groups' recall. Subsequent recall (short delay and long delay) for List 1 revealed significantly poorer recall for the MS group and significantly poorer cued recall but not recognition memory. Retrieval processes were implicated such as source memory, or contextual stamping, rather than encoding mechanisms.

Executive functions of the frontal lobes: psychometric properties of a self-rating scale.

This study investigated the psychometric properties of a self-rating scale designed to test the executive functions of the frontal lobes. A set of 16 items was selected, based on face validity, from the 200-item Coolidge Axis II Inventory. Cronbach scale reliability for the new scale was .72 on 1,223 purportedly normal participants. A factor analysis yielded a three-factor structure, Decision-making difficulties (8 items, 23% of the variance, scale reliability .77), Poor planning (4 items, 15% of the variance, scale reliability .63), and Task incompletion (6 items, 9% of the variance, scale reliability .66). A multivariate analysis of variance, performed on the overall scale sum and the three subscales, between 17 closed head-injured patients and a matched control group was significant. The head-injured patients scored significantly higher on the over-all measure of executive dysfunction and higher on the decision-making difficulties subscale but not on the other two subscales.

Gas chromatographic-mass spectrometric identification and quantitation of ethylene glycol in serum after derivatization with perfluorooctanoyl chloride: a novel derivative.

Ethylene glycol poisoning is a common clinical problem and identification as well as quantitation of ethylene glycol in serum is important for medical and legal purposes. Most investigators described determination of ethylene glycol by gas chromatography without derivatization or derivatives forming a molecular ion < 200. We describe a novel derivatization technique of ethylene glycol using perfluorooctanoyl chloride, after extraction from serum using acetone. This derivative has a molecular mass of 854 and produces a base peak at m/z 441 and other diagnostic strong peaks for unambiguous identification. Moreover, this derivative is less volatile and is free from interferences from endogenous serum components. Quantitation can be achieved by using 1,4-butanediol as an internal standard. The assay showed within-run and between-run precision of 7.2% and 8.0%, respectively, and linearity over the serum ethylene glycol concentration range 70-2240 micrograms/ml with a detection limit of 5 micrograms/ml.