Sources and space-time distribution of the electromagnetic pulses in experiments on inertial confinement fusion and laser-plasma acceleration.

When high-energy and high-power lasers interact with matter, a significant part of the incoming laser energy is transformed into transient electromagnetic pulses (EMPs) in the range of radiofrequencies and microwaves. These fields can reach high intensities and can potentially represent a significative danger for the electronic devices placed near the interaction point. Thus, the comprehension of the origin of these electromagnetic fields and of their distribution is of primary importance for the safe operation of high-power and high-energy laser facilities, but also for the possible use of these high fields in several promising applications. A recognized main source of EMPs is the target positive charging caused by the fast-electron emission due to laser-plasma interactions. The fast charging induces high neutralization currents from the conductive walls of the vacuum chamber through the target holder. However, other mechanisms related to the laser-target interaction are also capable of generating intense electromagnetic fields. Several possible sources of EMPs are discussed here and compared for high-energy and high-intensity laser-matter interactions, typical for inertial confinement fusion and laser-plasma acceleration. The possible effects on the electromagnetic field distribution within the experimental chamber, due to particle beams and plasma emitted from the target, are also described. This article is part of a discussion meeting issue 'Prospects for high gain inertial fusion energy (part 2)'.

Measurement of the plasma astrophysical S factor for the 3He(d,p)4He reaction in exploding molecular clusters.

The plasma astrophysical S factor for the 3He(d,p)4He fusion reaction was measured for the first time at temperatures of few keV, using the interaction of intense ultrafast laser pulses with molecular deuterium clusters mixed with 3He atoms. Different proportions of D2 and 3He or CD4 and 3He were mixed in the gas target in order to allow the measurement of the cross section for the 3He(d,p)4He reaction. The yield of 14.7 MeV protons from the 3He(d,p)4He reaction was measured in order to extract the astrophysical S factor at low energies. Our result is in agreement with other S factor parametrizations found in the literature.

Temperature measurements of fusion plasmas produced by Petawatt-Laser-Irradiated D2 - (3)He or CD4 - (3)He clustering gases.

Two different methods have been employed to determine the plasma temperature in a laser-cluster fusion experiment on the Texas Petawatt laser. In the first, the temperature was derived from time-of-flight data of deuterium ions ejected from exploding D(2) or CD(4) clusters. In the second, the temperature was measured from the ratio of the rates of two different nuclear fusion reactions occurring in the plasma at the same time: D(d,(3)He)n and (3)He(d,p)(4)He. The temperatures determined by these two methods agree well, which indicates that (i) the ion energy distribution is not significantly distorted when ions travel in the disassembling plasma; (ii) the kinetic energy of deuterium ions, especially the "hottest part" responsible for nuclear fusion, is well described by a near-Maxwellian distribution.

Accurate spectra for high energy ions by advanced time-of-flight diamond-detector schemes in experiments with high energy and intensity lasers.

Time-Of-Flight (TOF) methods are very effective to detect particles accelerated in laser-plasma interactions, but they show significant limitations when used in experiments with high energy and intensity lasers, where both high-energy ions and remarkable levels of ElectroMagnetic Pulses (EMPs) in the radiofrequency-microwave range are generated. Here we describe a novel advanced diagnostic method for the characterization of protons accelerated by intense matter interactions with high-energy and high-intensity ultra-short laser pulses up to the femtosecond and even future attosecond range. The method employs a stacked diamond detector structure and the TOF technique, featuring high sensitivity, high resolution, high radiation hardness and high signal-to-noise ratio in environments heavily affected by remarkable EMP fields. A detailed study on the use, the optimization and the properties of a single module of the stack is here described for an experiment where a fast diamond detector is employed in an highly EMP-polluted environment. Accurate calibrated spectra of accelerated protons are presented from an experiment with the femtosecond Flame laser (beyond 100 TW power and ~ 1019 W/cm2 intensity) interacting with thin foil targets. The results can be readily applied to the case of complex stack configurations and to more general experimental conditions.

Psychosocial profile of patients on the liver transplant list.

INTRODUCTION: Researchers have shown that psychosocial factors influence adherence to treatment and, consequently, prognosis. Psychosocial assessment during the preoperative outpatient phase has allowed physicians to make better treatment decisions. OBJECTIVES: We sought to describe the psychosocial profile of patients on the liver transplant list referred for psychological assessment. METHOD: We reviewed all files of patients referred for pretransplant psychological assessment over a 14-month period. RESULTS: The sample included 73 patients: mean age 49.46 +/- 11.18 years and; mean formal schooling 7.35 +/- 4.65 years. Of those, 56.1% reported a cognitive complaint; 33%, symptoms of anxiety, and 17%, depression. Of the sample, 45.8% were referred for alcohol use, and 37.5% for mood changes. During the assessment, 15.9%, 34.4%, and 1.6%, of patients reported using alcohol, tobacco, or some other type of drug, respectively. Of patients, 53.6% reported having used alcohol at some point in their life-26% tobacco and 10.9% some other type of drug. After the assessment, the main referrals were 35.6% to family counseling, 32.1% to cognitive assessment, and 28.5% to psychological counseling. CONCLUSION: This study highlighted the prevalence of cognitive complaints and current/previous use of chemical substances. These findings were identified through psychological inquiry, which was able to direct the individual treatments. Although these conditions prevailed among this population, their early detection allowed for early intervention to improve adherence and minimize possible intervening problems.

Neuropsychological assessment in kidney and liver transplantation candidates.

INTRODUCTION: Chronic renal and liver diseases are associated with cognitive and intellectual impairment, which can be irreversible even after kidney or liver transplantation. OBJECTIVE: We sought to investigate the presence of cognitive deficits in organ transplantation candidates. METHODS: From May 2005 to March 2006, 35 organ transplantation candidates, of mean age 46.71 (+/- 13.01) years, 54.3% including females and 7.29 (+/- 4.22) years mean formal schooling. Of those, 27 (77%) were renal and 8 (23%), liver transplantation candidates. All subjects underwent a neuropsychological assessment battery designed to evaluate attention performance, executive functions, memory, language, visuaospatial, and intellectual skills. RESULTS: We found impairments in attention performance (attention span [34.3%], sustained attention [76.5%], and divided attention [77.8%]), executive functions (category formation [58.3%], errors [61.5%], and perseverative errors [30.4%]), memory (working memory [57.1%], verbal [37.1%] and visual short-term memory [31.4%], verbal [25.7%] and visual long-term memory [51.4], verbal learning [42.9%], interference susceptibility [42.9%], and verbal recognition memory [20.6%]), language (comprehension [38.1%], and vocabulary [30.8%]), visuaospatial (45.8%), and intellectual skills (50.0%). CONCLUSION: Neuropsychological (cognitive) deficits in transplant candidates are frequent, regardless of the kind of transplantation. The deficits involve several cognitive skills, such as attentional processes, executive functions, memory, language, visuaospatial, and intellectual skills. Therefore, we concluded that a pretransplant neuropsychological assessment is an important measure to detect impairments and to help understand how these difficulties can interfere with patient self-care before and after transplantation.

Evaluation of efficacy in a liver pretransplantation orientation group.

BACKGROUND: The medical context recognizes the efficiency of working with groups of patients. Group interventions can intensify the understanding, ability, and notion of recognizing the patient's own condition, increasing the responsibility for him- or herself. This survey sought to evaluate the efficacy of an interdisciplinary orientation group for hepatic transplantation preoperatively. MATERIALS AND METHODS: The opinions of all patients on a waiting list for liver transplantation and their accompanying persons were evaluated from August to December 2005 through a questionnaire with 17 relevant items concerning the transplantation process. The group efficacy was evaluated according to the percentage of correct answers from the subjects before and after attending the group. RESULTS: The results showed a 59% increase in correct answers for the evaluated items after group attendance. The items which showed significant improvement were: what should I do after being called for transplantation; average time of admission to hospital and ICU; use of immunosuppressive drugs; clinical conditions for transplantation; frequency of appointments with the surgeon within the first month; physical activities; diet; blood transfusion; and forgetting medication. A ceiling effect was observed upon reevaluation of the previous conditions for transplantation item. CONCLUSIONS: The percentage of health improvement after attending the group demonstrated an impact of the interdisciplinary orientation intervention on the instruction of patients and their accompanying persons, thus representing an important step in their training process.

Evaluation of efficacy in a pancreas and pancreas-kidney pretransplantation orientation group.

BACKGROUND: There is evidence of benefits from psycho-educational groups in the compliance of patients undergoing complex procedures. Psycho-educational groups provide information, elucidate doubts and realities, fade out fantasies, and help lessen patients' anxieties, thus minimizing the chances of complications or irregular behavior. The objective of this study was to evaluate the efficacy of an interdisciplinary orientation group for pretransplantation preparation for pancreas/pancreas-kidney grafting. MATERIALS AND METHODS: All patients and their accompanying persons who attended information groups from February to August 2005 completed a questionnaire with 15 relevant items about the transplantation process. The efficiency of the orientation group was evaluated according to the percentage of correct answers before and after attending the group. RESULTS: Twenty-seven subjects were evaluated demonstrating an increased number of right answers in 78% of the evaluated items after group attendance. An important improvement was observed in the following items: function of serum sent to the Central Laboratory; serum replacement period; kind of renal donor; blood transfusion; using medicaments; and how often should the patient return for an appointment with the surgeon within the first month. Further items such as surgery risks, using immunosuppressive drugs, and forgetting the medication showed 100% correct answers before and after attending the group. CONCLUSIONS: Results suggest that the pretransplantation orientation group is an efficient way to provide information. Applying a knowledge verification questionnaire before and after the group helps to understand the difficulties of participants, thereby guiding the team and elucidating questions that need more consideration.

Time-resolved absolute measurements by electro-optic effect of giant electromagnetic pulses due to laser-plasma interaction in nanosecond regime.

We describe the first electro-optical absolute measurements of electromagnetic pulses (EMPs) generated by laser-plasma interaction in nanosecond regime. Laser intensities are inertial-confinement-fusion (ICF) relevant and wavelength is 1054 nm. These are the first direct EMP amplitude measurements with the detector rather close and in direct view of the plasma. A maximum field of 261 kV/m was measured, two orders of magnitude higher than previous measurements by conductive probes on nanosecond regime lasers with much higher energy. The analysis of measurements and of particle-in-cell simulations indicates that signals match the emission of charged particles detected in the same experiment, and suggests that anisotropic particle emission from target, X-ray photoionization and charge implantation on surfaces directly exposed to plasma, could be important EMP contributions. Significant information achieved on EMP features and sources is crucial for future plants of laser-plasma acceleration and inertial-confinement-fusion and for the use as effective plasma diagnostics. It also opens to remarkable applications of laser-plasma interaction as intense source of RF-microwaves for studies on materials and devices, EMP-radiation-hardening and electromagnetic compatibility. The demonstrated extreme effectivity of electric-fields detection in laser-plasma context by electro-optic effect, leads to great potential for characterization of laser-plasma interaction and generated Terahertz radiation.

Strict co-linearity of genetic and protein folding domains in an intragenically duplicated rat lens gamma-crystallin gene.

Two complementary DNA clones pRL gamma-2 and pRL gamma-3 of different rat lens gamma-crystallin messenger RNAs have been used to identify gamma-crystallin gene sequences in rat genomic DNA. Subsequently, the DNA present in the 18,000 to 20,000 bases region of the EcoRI digest, giving rise to a strong doublet hybridization signal, was cloned in lambda phage Charon-4A. One of the clones, lambda RCH gamma-3, carrying an insert of 17,500 bases has been characterized in detail. From analysis at the restriction enzyme level with 5'-, "middle" and 3'-specific subprobes of pRL gamma-3 it could be deduced that lambda RCH gamma-3 contains only one gamma-crystallin gene. The coding sequences of this gene are interrupted by intronic DNA. The primary structure of this gene and its flanking regions have been established by sequencing the relevant regions of a subclone of lambda RCH gamma-3, designated pRCH gamma-3 . 1. The sequence data show that the gamma-crystallin gene extends over 2700 bases of rat genomic DNA. The gene is split by two introns, one of 87 base-pairs after the third translation codon and a large one of 1880 base-pairs after codon 84. The mosaic structure of the gene is strictly co-linear with the structure of the gamma-crystallin polypeptide in that the large intron is positioned in a region which specifies the so-called "connecting peptide" and which links the two highly symmetrical and homologous protein domains. Although expected from the cDNA and protein sequence no introns were observed between the coding regions in the DNA specifying the two homologous folding motifs present in each protein domain. The relevance of this phenomenon in terms of the evolution of the mature gamma-crystallin gene is discussed.

[Thoracic pain, dyspnea]. / Thoraxschmerzen, Dyspnoe.

A 54-year old patient was admitted to the hospital with chest pain, dyspnea and left-sided pleural effusion, which was confirmed by a radiograph of the chest. In view of an exposure to asbestosis a CT scan of the chest was performed, which showed pleural thickening. The suspected diagnosis of a malignant mesothelioma was confirmed by needle biopsy of a paraaortic lymph node. Because of the existence of metastases a palliative pleurectomy was performed. Histologically a malignant mesothelioma of the biphasic type was found. The patient died less than half a year later from local progression of the tumor.

Experimental study of fusion neutron and proton yields produced by petawatt-laser-irradiated D2-³He or CD4-³He clustering gases.

We report on experiments in which the Texas Petawatt laser irradiated a mixture of deuterium or deuterated methane clusters and helium-3 gas, generating three types of nuclear fusion reactions: D(d,^{3}He)n, D(d,t)p, and ^{3}He(d,p)^{4}He. We measured the yields of fusion neutrons and protons from these reactions and found them to agree with yields based on a simple cylindrical plasma model using known cross sections and measured plasma parameters. Within our measurement errors, the fusion products were isotropically distributed. Plasma temperatures, important for the cross sections, were determined by two independent methods: (1) deuterium ion time of flight and (2) utilizing the ratio of neutron yield to proton yield from D(d,^{3}He)n and ^{3}He(d,p)^{4}He reactions, respectively. This experiment produced the highest ion temperature ever achieved with laser-irradiated deuterium clusters.

Versatile Escherichia coli-Bacillus shuttle vectors derived from runaway replication plasmids related to CloDF13.

Versatile cloning vectors were constructed employing a runaway replication mutant of the bacteriocinogenic plasmid CloDF13. These vectors can, under conditions where protein synthesis is not inhibited, be amplified in Escherichia coli to high levels by elevating the temperature and are therefore useful for the production of large quantities of DNA and protein. Since the constructed shuttle vectors, which harbour at least six unique restriction endonucleases sites, replicate in E. coli, Enterobacter cloacae, Staphylococcus aureus and a variety of Bacilli, they are applicable for the genetic engineering of both gram-negative and gram-positive bacteria.

Mutants of the Clo DF13 plasmid in Escherichia coli with a decreased bacteriocinogenic activity.

Three Clo DF13 mutant plasmids (designated as clp03, clp05 and clp21) that show a decreased cloacin activity were isolated. The decreased cloacin activity was not due to a reduced number of Clo DF13 copies per cell. The cloacins produced by the clp03 and the clp21 mutant plasmids have a strongly decreased killing activity in vivo in comparison with the wild type cloacin and the cloacin of the clp05 mutant plasmid. Furthermore no lacunae could be observed from clp03 or clp21 harbouring strains, while strains harbouring the clp05 plasmid showed a 50-100 times decreased frequency of lacunae. In addition the clp05 mutant showed a decreased rate of RNA synthesis in clp05 harbouring Escherichia coli minicells. No complementation between the three mutant plasmids was observed. We suggest that the clp03 and clp21 mutations are located in the gene coding for the cloacin. Since the cloacin produced by the clp05 mutant plasmid has retained all the known wild type cloacin activities, the reduced inhibition zone in the stab test is probably caused by a mutation affecting the expression of the cloacin gene. The nature of this mutation is discussed.

Isolation and characterization of a Clo DF13::Tn901 plasmid mutant with thermosensitive control of DNA replication.

After nitrosoguanidine mutagenesis, a mutant Escherichia coli strain harboring the Clo DF13::Tn901 plasmid pJN03 was isolated that is thermosensitive (Ts) for growth at 43 degrees C. The mutation responsible for this thermosensitive phenotype resides on the pJN03 plasmid genome. Cells harboring the pJN03 cop-1(Ts) plasmid mutant showed a large increase in plasmid copy number at 43 degrees C accompanied by an increase in the synthesis of plasmid-specified gene products like cloacin DF13 and beta-lactamase. The pJN03 cop-1(Ts) mutant showed uncontrolled plasmid DNA replication at the nonpermissive temperature. Analysis of plasmid deletions showed that the mutation is located in the Clo DF13 map interval from 0 to 12% or 29 to 45%. This implies that native cloacin DF13 and the Clo DF13-specified polypeptides B, C, D, E, and G are not involved in the pleiotropic phenotype of the plasmid mutant pJN03 cop-1(Ts).

Genetic map of the bacteriocinogenic plasmid CLO DF13 derived by insertion of the transposon Tn901.

An ampicillin transposon Tn901 was used as a "mutagen" to isolate insertion mutants of the bacteriocinogenic plasmid Clo DF13. By combining the obtained heteroduplex and restriction maps of the Clo DF13::Tn901 plasmids (van Emboden et al., 1977b) with their polypeptide pattern in minicells, we were able to map five genes on the Clo DF13 genome. These five genes designated A (cloacin gene), B, C, D, and G cover 55% of the coding capacity of Clo DF13 DNA. Since integration of Tn901 within these five genes did not result in a loss of the Clo DF13::Tn901 plasmids involved, it is suggested that these genes do not play an essential role in the maintenance of these plasmid insertion mutants. In addition, the described methods allowed us to indicate the initiation site of cloacin synthesis and to propose the counter-clockwise direction of transcription of the cloacin gene. The Tn901 DNA directed the synthesis of at least three polypeptides one of which is shown to be a TEM-1 beta-lactamase.

Clo DF13 plasmid deoxyribonucleic acid-directed in vitro synthesis of biologically active cloacin DF13 and clo DF13 immunity protein.

Clo DF13 plasmid deoxyribonucleic acid (DNA) was used as a template to direct transcription and translation in a DNA-dependent cell-free system prepared from Escherichia coli. Analysis of the invitro products on sodium dodecylsulfate-polyacrylamide gels revealed that Clo DF13 DNA directs the synthesis of at least 10 polypeptides ranging in molecular weight from approximately 7,000 to 70,000. Two of these polypeptides could be identified, with respect to their physiochemical and biological characteristics, as the products of the Clo DF13 genes coding for cloacin DF13 and Clo DF13 immunity protein. These results confirm previous findings, obtained which Clo DF13-harbouring minicells of E. coli, that the structural tenes for the latter proteins residue on the Clo DF13 genome.

Molecular cloning of mRNA sequences encoding rat lens crystallins.

To provide access to crystallin-specific DNA sequences, we have constructed plasmid clones bearing duplex DNA sequences complementary to crystallin mRNAs isolated from rat lens. Optimization of the cDNA reaction conditions enabled us to fractionate three double-stranded (ds) cDNA groups. Molecular cloning of dC-tailed ds cDNAs into the Pst I site of dG-tailed pBR322 yielded crystallin-specific clones of each group. By means of positive hybridization selection and translation, recombinant plasmids containing cDNA sequences coding for rat lens polypeptides from alpha-, beta-, and gamma-crystallins could be identified. The established cDNA clones have been used for a blot-hybridization analysis to map the crystallin mRNAs from which they originated. Both procedures revealed a high degree of homology between the gamma-crystallin sequences. From the beta-crystallin class, the beta H-specific cDNA coding for the beta B1a polypeptide was obtained. The alpha A-chain clone did not show any cross-hybridization to the alpha B-chain mRNA despite the existence of 60% homology between the corresponding gene products. As this clone hybridized to both alpha A2 and alpha AIns mRNAs, sequence analysis was applied for further characterization. The results showed that the cloned cDNA corresponds to the alpha A2 sequence exclusively.

An unusually long non-coding region in rat lens alpha-crystallin messenger RNA.

Most of the mRNA sequence coding for the alpha A2 chain of the ocular lens protein alpha-crystallin from rat, has been determined by sequencing cloned DNA copies of this mRNA. The 892-base pair cDNA sequence encompasses all but 52 N-terminal amino acids of the alpha A2 chain. It lacks the sequence characteristic for the 22 extra amino acids inserted in the alpha A2 -like chain, named alpha AIns. A stretch of 583 nuceotides, representing more than 50% of the entire mRNA sequence, is located 3' wards of the alpha A2 coding sequence. It contains the characteristic AAUAAA signal involved in poly(A) -addition and represents an unexpectedly long non-coding region. Examination of the total cytoplasmic poly(A) RNA of rat lens by filter-hybridization and subsequent translation of the electrophoretically separated mRNA fractions shows that the alpha A2 chain is encoded by mRNA species which are distinct from the alpha AIns encoding mRNA. No evidence is obtained for an extensive size heterogeneity in the 3' untranslated regions of these two different rat lens mRNAs.