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We have commenced experiments with intense short pulses of ion beams on the Neutralized Drift Compression Experiment-II at Lawrence Berkeley National Laboratory, by generating beam spots size with radius r <1 mm within 2 ns FWHM and approximately 10 10 ions/pulse. To enable the short pulse durations and mm-scale focal spot radii, the 1.2 MeV Li + ion beam is neutralized in a 1.6-meter drift compression section located after the last accelerator magnet. An 8-Tesla short focal length solenoid compresses the beam in the presence of the large volume plasma near the end of this section before the target. The scientific topics to be explored are warm dense matter, the dynamics of radiation damage in materials, and intense beam and beam-plasma physics including selected topics of relevance to the development of heavy-ion drivers for inertial fusion energy. Here we describe the accelerator commissioning and time-resolved ionoluminescence measurements of yttrium aluminum perovskite using the fully integrated accelerator and neutralized drift compression components. [ABSTRACT FROM AUTHOR]

Nonconventional oil is usually heavy and extra heavy crude or light oil that is relatively unstable. This oil contains varying proportions of larger, more aromatic constituents rather than molecules that can be distilled directly into fuels and petrochemicals. We perform density functional theory (ωB97X-D/6-31G(d,p)) calculations to study the contributions of steric effects and dispersion interactions in a series of dimers and trimers of model hydrocarbons containing fused aromatic and cyclohexyl (referred to in the petroleum literature as naphthenic) rings. The aggregation behavior of these molecules is analyzed in terms of the optimized geometry, atomic charges, interaction enthalpy (∆H), and Gibbs free energy (∆G298). The ∆H and ∆G298 values show that all the processes are exothermic, and only a few are spontaneous at 298 K. The naphthenic hydrogen atoms have a key role in the orientation of the monomers in dimer and trimer aggregates. The interaction among naphthenic hydrogen atoms belonging to adjacent monomers causes steric repulsion. The interaction of naphthenic hydrogen atoms with the π-electronic clouds of aromatic rings in adjacent molecules causes attraction. In both cases, the naphthenic hydrogen atoms cause deviation of the monomer from the initial parallel displaced configuration in dimers and trimers. These results reflect the importance of naphthenic rings and their steric interactions in determining the relationship between structures of nonconventional petroleum constituents and their tendency to aggregate and cause fouling. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Induction accelerators are appealing for heavy-ion driven inertial fusion energy (HIF) because of their high efficiency and their demonstrated capability to accelerate high beam current (≥10kA in some applications). For the HIF application, accomplishments and challenges are summarized. HIF research and development has demonstrated the production of single ion beams with the required emittance, current, and energy suitable for injection into an induction linear accelerator. Driver scale beams have been transported in quadrupole channels of the order of 10% of the number of quadrupoles of a driver. We review the design and operation of induction accelerators and the relevant aspects of their use as drivers for HIF. We describe intermediate research steps that would provide the basis for a heavy-ion research facility capable of heating matter to fusion relevant temperatures and densities, and also to test and demonstrate an accelerator architecture that scales well to a fusion power plant. [Copyright &y& Elsevier]

Abstract: This work verifies the impact of lubricant viscosity and viscosity improver additives on diesel fuel economy. Eight lubricants were tested in a single-cylinder, four-stroke, direct injection diesel engine mounted on a dynamometer, under different load and speed conditions. Engine friction power was also investigated through Willans’ line. The results demonstrate that fuel economy obtained from multigrade viscosity oils is higher than that obtained from monograde viscosity oils. A linear relationship was obtained between the high temperature high shear viscosity and specific fuel consumption. The lubricant which provided lower fuel consumption also required lower friction power. [ABSTRACT FROM AUTHOR]

Initiatives concerning the development of Green Chemistry began in the early 1999, mainly in the United States, Britain and Italy, with the introduction of new concepts and values for the various fundamental activities of Chemistry, as well as for different sectors of correlated industrial and economic activities. Brazil has several competitive advantages to assume a leadership in developing products from biomass, given its megabiodiversity, its solar radiation intensity and climate diversity. Additionally, the country is pioneer in biofuels production from biomass in large scale, especially ethanol from sugarcane. In fact, several opportunities of green innovations by adding value to raw materials have been identified for the country. These opportunities when implemented will contribute to a significant change - from a commodity export economy to an innovative market oriented economy based on high-value bioproducts and bioprocesses - the bioeconomy. In this context, this paper presents a future vision for the development of Green Chemistry in Brazil and a proposal for creating the Green Chemistry Brazilian Network and the Brazilian School of Green Chemistry, within the context of a national strategy for developing this area in Brazil covering the period of twenty years, from 2010 to 2030. [ABSTRACT FROM AUTHOR]

Abstract: Camphor and norcamphor derivatives provide convenient models for testing and evaluating some of the results of our work on substituted adamantanes and for checking their applicability to other systems. Our results show that the reduction in C–H bond lengths associated with steric interactions are not as pronounced in systems that are less rigid. Deshielding of 1H chemical shifts on introduction of the substituent in exo and endo positions can also be traced to angular distortions which are stronger in norcamphor, bornane and camphor than in norbornane due to additional steric interactions with a carbonyl group, with methyl groups, or with both. 1H chemical shifts are sensitive probes for steric effects, reflecting differences in bond lengths, bond angles and dihedral angles in a systematic way. Given the proper models for comparison purposes they can be used to evaluate the size of a certain group and locate its interactions with the rest of the molecular framework. [Copyright &y& Elsevier]

Abstract: The synthesis of new ribonucleosides is an essential research area in the investigation of new therapeutically useful agents, particularly those used in the treatment of HIV infection. The conformation of these nucleosides may have direct implications for their ability to bind to receptor targets. We have prepared the 7-methoxy-1,4-dihydro-4-oxoquinoline-3-carboxylic acid derivatives and used the ensemble of low-energy minima to develop conformational profiles of quinolonic nucleosides and verify their accuracy in different calculations of structural parameters. Results are compared with experimental data obtained by X-ray and NMR analysis. Finally, we intend to test the applicability of these methods to conformational analysis of other nucleosides and verify if the preferential conformation is the one which gives the best anti-HIV or antiviral activity. [Copyright &y& Elsevier]

Previous theoretical studies indicate that hyperconjugation and through-space interactions of a steric or electronic nature are mainly responsible for conformational effects in half-cage systems, influencing bond lengths, bond angles and dihedral angles as well as charge distributions. As chemical shieldings are likewise affected, it is of much interest to evaluate their contributions in order to use them for structure elucidation purposes (calculating chemical shifts for individual rotamers has the advantage of detecting effects that would otherwise appear as averages in observed spectra). Half-cage systems provide interesting models due to their rigid molecular framework. On rotation of the single C–O bond of half-cage alcohol derivatives, different groups are forced into close proximity. In our investigation of conformational effects on chemical shifts of “inside” and “outside” half-cage alcohols we found that certain positions on the inside (2) isomer did not reproduce effects observed for the outside (1) isomer. To probe interactions between lone pairs on oxygen and the C9–H9s bond, we used DFT B3LYP/6-31g(d) methodology to optimize geometries and to calculate the second order interaction energy and chemical shifts at 30° intervals. We found that not only is strong hyperconjugation through space present but, besides the oxygen p orbital, there is also a considerable contribution from the oxygen sp orbital. Although this result is not unexpected given the spatial proximity of the orbitals that are involved, to our knowledge the literature on hyperconjugation has, so far, been limited to participation by p orbitals on oxygen. [Copyright &y& Elsevier]

Half-cage compounds have played an important role in the investigation of the way steric compression affects physical and chemical properties of organic molecules. Recent theoretical studies of half-cage alcohols have also shown that rotation around the carbon–oxygen bond of the hydroxyl group leads to low-energy conformers in which hyperconjugation affects bond lengths, bond angles, and charge distribution on carbon and hydrogen atoms in its vicinity while charge distribution is also affected by electrostatic effects. Chemical shifts are also sensitive to such variations, but we found that in smaller model systems steric effects may strongly attenuate those due to hyperconjugation so we optimized geometries for low energy rotamers of ‘outside’ and ‘inside’ half-cage alcohols, where these effects can be separated, and calculated their respective hydrogen and carbon-13 chemical shifts by gauge-independent atomic orbital (GIAO) methods at the B3LYP/6-31G(d) level. Results are compared to those obtained for the corresponding norbornyl alcohols as well as for the half-cage hydrocarbon. Carbon-13 chemical shifts respond more strongly to effects owing to hyperconjugation while hydrogen chemical shifts are more sensitive to electrostatic effects due to the proximity of the hydroxyl group. [Copyright &y& Elsevier]

Presents an introductory course in industrial chemistry for freshmen. Aims to providing students basic attitudes and skills; Aid for learning calculus and classical mechanics; Response of the students to the course load.

An albumin-peptide conjugate was synthesized, which carries pentaglycine peptides with C-terminal glycine residues as found in the interpeptide bridges of the peptidoglycan of many staphylococci. Immunization of rabbits with this synthetic immunogen yielded antisera containing predominantly antibodies against the peptide moiety of the conjugate. The quantitative precipitin and the Ouchterlony agar gel reaction with several synthetic protein-peptide-conjugates, immunoaffinity chromatography of the antisera on Sepharose-(Gly-Gly-Gly-Gly-Gly)n and hapten inhibition studies with several synthetic peptides and peptide derivatives demonstrated that the antibodies were highly specific for oligoglycinc peptides with C-terminal glycine. These antibodies also reacted strongly with staphylococcal peptidoglycans with an interpeptide bridge composed of pentaglycine peptides or of pentaglycine peptides in which part of the glycine residues were replaced by L-serine. In contrast, all the peptidoglycans lacking interpeptide bridges composed of glycine residues gave no precipitin reaction at all. The final proof for identical determinant groups of albumin-(CH2CO-Gly-Gly-GlyGly-Gly)31 and the staphylococcal pcptidoglycans applied in the precipitin reaction was furnished by double gel diffusion studies and by hapten inhibition of the precipitin reaction between antisera to albumin-(CH2CO-Gly-Gly-Gly-Gly-Gly)31 and the correspond lag peptidoglycans. For rapid screening of the different peptidoglycans, a latex agglutination test was elaborated. Purified antibodies were adsorbed to latex particles, and the titers with the particular peptidoglycans were then determined. The test was highly sensitive, in that 10 nanograms of peptidoglycan could still be detected. [ABSTRACT FROM AUTHOR]

A pentapeptide, Gly-L-Ala-L-Ala-D-Ala-D-Ala, was synthesized and covalently linked with its free amino group to human serum albumin. Immunization of rabbits with this albumin-peptide Conjugate yielded antisera containing predominantly antibodies directed against the peptide. By means of inhibition studies with various amino-acid derivatives and related peptides, it was demonstrated that the antibodies are directed against the C-terminal portion of the pentapeptide and that D-alanyl-D-alanine is tile immunodominant site of the antigen. These antibodies showed also a specific cross-reaction with solubilized peptidoglycan containing peptide subunits with C-terminal D-alanyl-D-alanine and with another albumin-peptide conjugate carrying Gly-γ-D-Glu-L-Ala-D-Ala-D-ALa pentapeptide residues. These albumin-peptide conjugates also reacted with rabbit antisera of Streptococcus group-A-variant which contain antibodies directed against the peptide moiety of the peptidoglycan. Double-gel diffusion studies with antiserum to Streptococcus group-A-variant or to albumin-peptide conjugate as antibody source and albumin-peptide-conjugate and a soluble high molecular fraction of peptidoglycan as antigens yielded precipitin lines which completely fused. This indicates that these antigens have identical determinant groups with respect to the antisera employed. [ABSTRACT FROM AUTHOR]

The acidic fluids used in the acidification of oil wells can compromise metallic structures. As a consequence, corrosion inhibitors are needed to mitigate the corrosion process. Researches have been carried out on the use of eco-friendly corrosion inhibitors, which are obtained from low cost and sustainable source. In this work, Cashew nut shell liquid (CNSL), a by-product of the cashew nut industry, and the residue of its distillation (R) were evaluated as corrosion inhibitors for API P110 carbon steel in 15% HCl. The efficacy of eight organic formulations was assessed by mass loss, potentiodynamic polarization, linear polarization resistance and electrochemical impedance. CNSL and R were characterized by FTIR, 1H NMR and TGA. The mass loss tests (298–353 K) revealed maximum efficiency of 99.47%, which was confirmed by electrochemical measurements. The formulations acted as mixed inhibitors. Molecular adsorption probably occurs through the oxygens and π electrons of the aromatic rings in agreement with DFT results. The formation of an inhibitor film was confirmed by SEM-EDX and FTIR. This study reveals the importance of sustainable assets, such as cashew nut residues, that when properly purified and formulated may exhibit high corrosion inhibition efficiency, even under aggressive conditions found in the offshore oil and gas industry. In addition, it represents a more noble application for a by-product in terms of value aggregation. Unlabelled Image • Development of organic formulations for well acidizing; • Synergistic effect between CNSL and the Residue with Propargyl alcohol; • The corrosion rates are under the industry standard (5 mm/y) for two formulations (353K) and five formulations (333K); • Best efficiency was 99.47% at 353 K, showing that the formulation maintains its protection even in high temperature. [ABSTRACT FROM AUTHOR]

Background: Tinea capitis and tinea corporis are highly prevalent fungal skin infections, which globally are mainly caused by Microsporum canis and Trichophyton rubrum, respectively. While in the United States and Great Britain Trichophyton tonsurans is widely prevalent as a causative pathogen, it so far only plays a minor role in Germany. Objectives: Since the frequency of pathogenic species varies regionally and temporally, this study assesses the proportion of Trichophyton tonsurans infections in the dermatology department of a large university hospital in Germany from 2019 to 2022 and thoroughly characterises the affected patient population. Patients/Methods: This retrospective study at the Technical University of Munich analyses mycological culture results regarding the identified dermatophyte and infection site. Detailed patient and disease‐related information on Trichophyton tonsurans positive patients was obtained. Results: In 2022, 23 patients of 111 dermatophyte culture‐positive patients tested positive for Trichophyton tonsurans. This accounted for 20.7% and represented a tenfold increase from 2.1% in 2019. Contact sports were only practiced by 21.7% of patients, and no common hotspot or other linkage could be identified between the cases. Additionally, 47.8% of the patients received a systemic treatment, with 30.4% visiting the clinic more than three times. In 2022, 21.7% were diagnosed with a simultaneous infection of the capillitium and body, whereas this was only observed in 7.1% of cases in 2019 to 2021. Conclusions: This study suggests an increase of Trichophyton tonsurans infections via several routes of transmission. [ABSTRACT FROM AUTHOR]

Abstract: The adsorption of five asphalts processed in Brazilian refineries and designated as A, B, C, D and E, and their asphaltenes and maltenes constituents, from toluene solutions, onto quartz, feldspar and biotite and the relationship between this tendency and the mechanical properties of the asphalt pavement have been investigated. For all minerals asphalts A and C strongly absorbed the others. Their respective curves levelling off between 3.5 and 4.0 mg g−1 for gneiss and quartz, increasing to 5 and 6 mg g−1 for feldspar and biotite. The eletrophoretic mobility of quartz was not modified by the adsorption of asphaltenes in contrast to that observed for feldspar and biotite, indicating that the sites liable for the surface charge of the latter minerals were affected by the presence of the adsorbed organic species. Regarding the mechanical resistance tests for asphalt mixtures, only asphalts A and C gave that would be considered values acceptable by the Brazilian National Department of Terrestrial Infra-structure (DNIT) (>80%). Those results indicate that the chemical interaction among minerals and asphalts should affect for good or bad the mechanical resistance of the asphalt mixture. [Copyright &y& Elsevier]

Abstract: A conformational search of average structures of asphaltenes containing heteratom and a study of aggregation process were made by the MM/QM method. For the asphaltene A monomer, the minimum energy structure corresponds to the SRR conformation. Results for the asphaltene B monomer were not conclusive because the AM1 and ZINDO methods lead to different results: for the AM1 method, the minimum energy structure corresponds to the SSR monomer while for the ZINDO method the energy minimum corresponds to the SRS monomer. The aggregation process was observed and the ΔE of formation of the aggregates were −58.91 and −45.07kcal/mol, respectively, for A and B asphaltenes. The more important differences between monomers and dimers were analysed. [Copyright &y& Elsevier]

Our calculations on bi- and polycyclic alcohols reveal that the Mulliken charge distribution and chemical shift patterns due to hyperconjugation of lone pairs on oxygen with neighboring groups break down or are attenuated for certain spatial relationships of the hydroxyl group. Since in strained ring systems other effects on these parameters may be present, we applied a similar analysis to acyclic alcohols. Calculations at the B3LYP/6-31G&ast; level on conformers of methanol, ethanol, 1- and 2-propanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 2-butanol, 2-methyl-2-butanol, 1- 2- and 3-pentanol and 2-methyl-3-pentanol, where hyperconjugation may be present, reveal steric effects as modifiers of hyperconjugative patterns affecting carbon-13 chemical shifts in such alcohols. Contrary to what is observed in bi- and policyclic systems, where electrostatic effects interfere with effects due to hyperconjugation, these steric effects may be the main cause for the attenuation of deshielding of nuclei that are subject to hyperconjugation. Electrostatic effects are also present but they do not interfere with hyperconjugation by lone pairs. Conformational effects fall off sharply after the third carbon in the chain. [Copyright &y& Elsevier]

The synergism in an organic formulation containing propargyl alcohol, octadecylamine, and 1,3-dibutyl thiourea was evaluated. The formulation efficiency was tested for API P110 steel in acetic + formic acidic media by weight loss, potentiodynamic polarization, linear polarization resistance, confocal laser scanning microscopy, and scanning electron microscopy. The formulation was characterized using Fourier transform infrared spectroscopy. Gravimetric analysis (353–393 K) revealed efficiencies above 98% and confirmed the importance of the multi-component formulation, which acts as a mixed-type inhibitor. The inhibiting film was confirmed by scanning electron microscopy. The substances evaluated show a synergistic effect when employed together. [ABSTRACT FROM AUTHOR]

Mild carbon steel is widely used in construction materials owing to its relatively low price, ease of manufacture and high tensile strength. When it is subjected to an aggressive environment, the use of efficient corrosion inhibitors is required. The offshore oil and gas industry apply well stimulation techniques employing strong acids (5–35 wt%), which severely damage metallic structures. Conventional inhibitors may result in environmental and human health problems. In order to avoid that, green compounds have been widely investigated. However in certain applications, such as materials for offshore installations, protection is afforded by multi-component formulations. The synergistic effect of formulations is achieved by the active compounds, intensifiers, surfactants and solvents. Thus the performance of three Schiff bases synthesized from vanillin, a green aldehyde, and aromatic amines was investigated in corrosion inhibition of carbon steel. Weight loss measurements were made in 2 M and 15% HCl over a 313K–353K temperature range in concentrations between 0.4%wt./v and 1.0%wt./v. Effects of binary and ternary mixtures in 15% HCl revealed an increased efficiency for isolated inhibitors at higher concentrations. The addition of potassium iodide enhanced efficiency to 97.78% in 15% HCl at 333 K. Electrochemical tests indicated mixed-type inhibitors. Surface analysis confirmed the presence of a protective film as well as reduced carbon steel roughness. Density-functional theory (DFT) calculations revealed the effects of a substituent on structural and electronic properties in the neutral and acid phases. The role of a sulfur atom in preventing corrosion was also addressed by DFT calculations. • Green Schiff bases with high inhibition efficiencies for industrial application. • The SB3 + KI blend exhibited the highest efficiency in 15% HCl (97.78%). • SB3 + KI achieved CR below 5 mm/y in 15% HCl, required for well stimulation. • SB3 was more easily protonated due to its additional heteroatom. • All SBs were chemically and physically adsorbed, following Langmuir isotherm. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT),Møller–Plesset second-orderperturbation theory (MP2), and semiempirical methods are employedfor the geometry optimization and thermochemistry analysis of π–πstacked di-, tri-, tetra-, and pentamer aggregates of the fused polycyclicaromatic hydrocarbons (PAHs) naphthalene, anthracene, phenanthrene,tetracene, pyrene, and coronene as well as benzene. These aggregates(stabilized by dispersion interactions) are highly relevant to theintermolecular aggregation of asphaltenes, major components of heavypetroleum. The strength of π–π stacking interactionis evaluated with respect to the π-stacking distance and thermochemistryresults, such as aggregation enthalpies, entropies, and Gibbs freeenergies (ΔG298). For both π-stackinginterplanar distances and thermochemistry, the ωB97X-D functionalwith an augmented damped R–6dispersioncorrection term and MP2 are in the closest agreement with the highlyaccurate spin-component scaled MP2 (SCS-MP2) method that we selectedas a reference. The ΔG298valuesindicate that the aggregation of coronene is spontaneous at 298 Kand the formation of pyrene dimers occurs spontaneously at temperaturelower than 250 K. Aggregates of smaller PAHs would be stable at evenlower temperature. These findings are supported by X-ray crystallographicdetermination results showing that among the PAHs studied only coroneneforms continuous stacked aggregates in single crystals, pyrene formsdimers, and smaller PAHs do not form π–π stackedaggregates. Thermochemistry analysis results show that PAHs containingmore than four fused benzene rings would spontaneously form aggregatesat 298 K. Also, round-shaped PAHs, such as phenanthrene and pyrene,form more stable aggregates than linear PAHs, such as anthracene andtetracene, due to decreased entropic penalty. These results are intendedto help guide the synthesis of model asphaltene compounds for spectroscopicstudies so as to help understand the aggregation behavior of heavypetroleum. [ABSTRACT FROM AUTHOR]

A 10.9cm diameter lithium alumino-silicate ion source has been chosen as a source of lithium ion current for the Neutralized Drift Compression Experiment (NDCX-II) at LBNL. Research and development was carried out on lithium alumino-silicate ion sources prior to NDCX-II source fabrication. Space-charge-limited emission with the current density exceeding 1mA/cm2 was measured with 0.64cm diameter lithium alumino-silicate ion sources at 1275°C. The beam current density is less for the first 10.9cm diameter NDCX-II source, and it may be due to an issue of surface coverage. The lifetime of a thin coated (on a tungsten substrate) source is varied, roughly 40–50h, when pulsed at 0.05Hz and with pulse length of each, i.e., a duty factor of 3×10−7, at an operating temperature of 1250–1275°C. The 10.9cm diameter source lifetime is likely the same as of a 0.64cm source, but the lifetime of a source with a 2mm diameter (without a tungsten substrate) is 10–15h with a duty factor of 1 (DC extraction). The lifetime variation is dependent on the amount of deposition of mass, and the surface temperature. The amount of mass deposition does not significantly alter the current density. More ion source work is needed to improve the large source performance. [ABSTRACT FROM AUTHOR]

Abstract: Neutralized drift compression offers an effective means for particle beam focusing and current amplification with applications to heavy ion fusion. In the Neutralized Drift Compression eXperiment-I (NDCX-I), a non-relativistic ion beam pulse is passed through an inductive bunching module that produces a longitudinal velocity modulation. Due to the applied velocity tilt, the beam pulse compresses during neutralized drift. The ion beam pulse can be compressed by a factor of more than 100; however, errors in the velocity modulation affect the compression ratio in complex ways. We have performed a study of how the longitudinal compression of a typical NDCX-I ion beam pulse is affected by the initial errors in the acquired velocity modulation. Without any voltage errors, an ideal compression is limited only by the initial energy spread of the ion beam, ΔΕ b . In the presence of large voltage errors, δU⪢ΔE b , the maximum compression ratio is found to be inversely proportional to the geometric mean of the relative error in velocity modulation and the relative intrinsic energy spread of the beam ions. Although small parts of a beam pulse can achieve high local values of compression ratio, the acquired velocity errors cause these parts to compress at different times, limiting the overall compression of the ion beam pulse. [Copyright &y& Elsevier]

Abstract: Eight human herpes viruses (e.g., herpes simplex, varicella-zoster, Epstein-Barr, cytomegalovirus, Kaposi’s sarcoma) are responsible for several diseases from sub-clinic manifestations to fatal infections, mostly in immunocompromised patients. The major limitations of the currently available antiviral drug therapy are drug resistance, host toxicity, and narrow spectrum of activity. However, some non-nucleoside 1,4-dihydro-4-oxoquinoline derivatives (e.g., PNU-183792) shows broad spectrum antiviral activity. We have developed molecular modeling studies, including molecular docking and molecular dynamics simulations, based on a model proposed by Liu and co-workers in order to understand the mechanism of action of a 6-chloro substituted 1,4-dihydro-4-oxoquinoline ribonucleoside, synthesized by the synthetic group, which showed anti-HSV-1 activity . The molecular docking simulations confirmed the Liu’s model showing that the ligand needs to dislocate template residues from the active site in order to interact with the viral DNA polymerase enzyme, reinforcing that the interaction with the Val823 residue is pivotal for the inhibitory activity of non-nucleoside 1,4-dihydro-4-oxoquinoline derivatives, such as PNU-183792, with the HSV-1. The molecular dynamics simulations showed that the 6-chloro-benzyl group of PNU-183792 maintains its interaction with residues of the HSV-1 DNA polymerase hydrophobic pocket, considered important according to the Liu’s model, and also showed that the methyl group bounded to the nitrogen atom from PNU-183792 is probably contributing to a push–pull effect with the carbonyl group. [Copyright &y& Elsevier]

Abstract: The infections caused by the Herpes Simplex Virus are one of the most common sources of diseases in adults and several natural nucleoside analogues are currently used in the treatment of these infections. In vitro tests of a series of quinolonic ribonucleosides derivatives synthesized by part of our group indicated that some of them have antiviral activity against HSV-1. The conformational analysis of bioactive compounds is extremely important in order to better understand their chemical structures and biological activity. In this work, we have carried out a nuclear relaxation NMR study of 6-Me ribonucleoside derivative in order to determine if the syn or anti conformation is preferential. The NMR analysis permits the determination of inter-atomic distances by using techniques which are based on nuclear relaxation and related phenomena. Those techniques are non-selective longitudinal or spin–lattice relaxation rates and NULL pulse sequence, which allow the determination of distances between pairs of hydrogen atoms. The results of NMR studies were compared with those obtained by molecular modeling. [Copyright &y& Elsevier]

We report results on lithium alumino-silicate ion source development in preparation for warm dense matter heating experiments on the new neutralized drift compression experiment II. The practical limit to the current density for a lithium alumino-silicate source is determined by the maximum operating temperature that the ion source can withstand before running into problems of heat transfer, melting of the alumino-silicate material, and emission lifetime. Using small prototype emitters, at a temperature of ≈1275 °C, a space-charge limited Li+ beam current density of J ≈1 mA/cm2 was obtained. The lifetime of the ion source was ≈50 h while pulsing at a rate of 0.033 Hz with a pulse duration of 5-6 μs. [ABSTRACT FROM AUTHOR]

Abstract: Plasmas are a source of unbound electrons for charge neutralizing intense heavy ion beams to focus them to a small spot size and compress their axial length. The plasma source should operate at low neutral pressures and without strong externally applied fields. To produce long plasma columns, sources based upon ferroelectric ceramics with large dielectric coefficients have been developed. The source utilizes the ferroelectric ceramic BaTiO3 to form metal plasma. The drift tube inner surface of the Neutralized Drift Compression Experiment (NDCX) is covered with ceramic material. High voltage (∼8kV) is applied between the drift tube and the front surface of the ceramics. A BaTiO3 source comprised of five 20-cm-long sources has been tested and characterized, producing relatively uniform plasma in the 5×1010 cm−3 density range. The source was integrated into the NDCX device for charge neutralization and beam compression experiments, and yielded current compression ratios ∼120. Present research is developing multi-meter-long and higher density sources to support beam compression experiments for high-energy-density physics applications. [Copyright &y& Elsevier]

Abstract: The high-current experiment (HCX) at LBNL is a driver scale single beam injector that provides a 1MeV K+ ion beam current of 0.18A for 5μs. It transports high-current beams with large fill factor (ratio of the maximum beam envelope radius to the beam pipe radius) and low emittance growth that are required to keep the cost of the power plant competitive and to satisfy the target requirements of focusing ion beams to high-power density. Beam interaction with the background gas and walls desorbs electrons that can multiply and accumulate, creating an electron cloud. This ubiquitous effect grows at higher fill factors and degrades the quality of the beam. We review simulations and diagnostics tools used to measure electron production, accumulation and its properties. [Copyright &y& Elsevier]

Abstract: Intense, space-charge-dominated ion beam pulses for warm dense matter and heavy ion fusion applications must undergo simultaneous transverse and longitudinal bunch compression in order to meet the requisite beam intensities desired at the target. The longitudinal compression of an ion bunch is achieved by imposing an initial axial velocity tilt on the drifting beam and subsequently neutralizing its space-charge and current in a drift region filled with high-density plasma. The Neutralized Drift Compression Experiment (NDCX) at Lawrence Berkeley National Laboratory has measured a sixty-fold longitudinal current compression of an intense ion beam with pulse duration of a few nanoseconds, in agreement with simulations and theory. A strong solenoid is modeled near the end of the drift region in order to transversely focus the beam to a sub-millimeter spot size coincident with the longitudinal focal plane. The charge and current neutralization provided by the background plasma is critical in determining the total achievable transverse and longitudinal compression of the beam pulse. Numerical simulations show that the current density of an NDCX ion beam can be compressed over a few meters by factors greater than 105 with peak beam density in excess of 1014 cm−3. The peak beam density sets a lower bound on the local plasma density required near the focal plane for optimal beam compression, since the simulations show stagnation of the compression when n beam>n plasma. Beam–plasma interactions can also have a deleterious effect on the compression physics and lead to the formation of nonlinear wave excitations in the plasma. Simulations that optimize designs for the simultaneous transverse and longitudinal focusing of an NDCX ion beam for future warm dense matter experiments are discussed. [Copyright &y& Elsevier]

Abstract: Longitudinal compression factors in excess of 50 of a 300-keV, 20-mA K+ ion beam have been demonstrated in the Neutralized Drift Compression Experiment (NDCX) in agreement with LSP particle-in-cell simulations using the experimental tilt voltage waveform. Here, pre-formed plasma provides beam neutralization for a 1–2-m drift length. To achieve simultaneous transverse and longitudinal compression, we must understand and account for the impact of the applied velocity tilt on the transverse phase space of the beam. Of equal importance to achieving warm dense matter and heavy ion fusion conditions, is quantifying the effect of beam plasma interactions, including stability and neutralization, on the beam transport throughout the drift section up to the target. Critical new issues relate to transverse focusing of the axially compressing ion beam in a high-field (3–15T) solenoid that is filled with plasma. Integrated LSP simulations that include modeling of the diode, magnetic transport, induction bunching module, plasma neutralized transport, solenoidal focusing and beam target interaction, are assisting in the design of a near-term warm dense matter experiment. We discuss the simulation algorithms and present calculations of designs for such an experiment that will heat an aluminum target up to roughly 1-eV temperature. [Copyright &y& Elsevier]

Abstract: Plasmas are a source of unbound electrons for charge neutralizing intense heavy ion beams to allow them to focus to a small spot size and compress their axial pulse length. The plasma source should be able to operate at low neutral pressures and without strong externally applied electric or magnetic fields. To produce 1m-long plasma columns, sources based upon ferroelectric ceramics with large dielectric coefficients are being developed. The sources utilize the ferroelectric ceramic BaTiO3 to form metal plasma. The drift tube inner surface of the Neutralized Drift Compression Experiment (NDCX) will be covered with ceramic material, and high voltage (∼7kV) will be applied between the drift tube and the front surface of the ceramics. A prototype ferroelectric source, 20cm in length, has produced plasma densities of 5×1011 cm−3. It was integrated into the Neutralized Transport Experiment (NTX), and successfully charge neutralized the K+ ion beam. A 1m-long source comprised of five 20-cm-long sources has been tested. Simply connecting the five sources in parallel to a single pulse forming network power supply yielded non-uniform performance due to the time-dependent nature of the load that each of the five plasma sources experiences. Other circuit combinations have been considered, including powering each source by its own supply. The 1-m-long source has now been successfully characterized, producing relatively uniform plasma over the 1m length of the source in the mid-1010 cm−3 density range. This source will be integrated into the NDCX device for charge neutralization and beam compression experiments. [Copyright &y& Elsevier]

Abstract: Conformational analysis of nucleosides may have direct applications to the structure–activity relationship (SAR) studies and in the design of new drug candidates. Although conformational analysis may be accessed in many different ways, in this work it was performed using molecular dynamics (MD) simulation in order to study the dynamic behavior of a nucleoside derivative of 1,4-dihydro-4-oxoquinoline-3-carboxylic acid, synthesized by our group as a potential antiviral agent. The MD simulation was carried out during 10ns in vacuum and in a box of water at two different temperatures (i.e., 300 and 600K) using the AMBER force field. The in vacuum MD simulation results are in agreement with the crystallographic structure and with the DFT calculations of the nucleoside, revealing the anti conformer as the more stable one. The simulation in water, however, shows that both conformers may exist at 300K, the temperature of the in vivo and in vitro assays, revealing that both the syn and anti conformers should be considered in a MD simulation study of the inhibitor–enzyme complex. Simulations are also in agreement with the NOE experiment, which shows that the anti conformer is the preferential one in DMSO-d6 solution at 298K. [Copyright &y& Elsevier]

The Heavy Ion Fusion (HIF) program is progressing through a series of physics and technology demonstrations leading to an inertial fusion power plant. The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is exploring the physics of intense beams with high line-charge density. Superconducting focusing quadrupoles were developed for magnetic transport studies at the HCX. A baseline design was selected following several pre-series models. Optimization of the baseline design led to the development of a first prototype that achieved a conductor-limited gradient of 132 T/m in a 70 mm bore, without training, with measured field errors at the 0.1% level. Based on these results, the magnet geometry and fabrication procedures were adjusted to improve the field quality. These modifications were implemented in a second prototype. In this paper, the optimized design is presented and comparisons between the design harmonics and magnetic measurements performed on the new prototype are discussed. [ABSTRACT FROM AUTHOR]

Systematic investigations of conformational effects of the hydroxyl group on carbon or hydrogen chemical shifts of different types of alcohols reveal that, besides stereoelectronic effects, hyperconjugation with lone pairs may have a strong influence. In view of the growing use of chemical shifts in probing the structure of biologic molecules, we employed DFT/GIAO/NBO calculations at the B3LYP level for conformers obtained from partial optimization of structures resulting from 30° variations of the C—C—X—H (X=O, N) dihedral angles to verify if nitrogen responded in a fashion similar to oxygen. Although the hybridization and geometry of hydroxyl and amine groups are distinct, the lone pair on nitrogen reveals hyperconjugation with suitably positioned orbitals on alkyl groups. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 95: 322–328, 2003 [ABSTRACT FROM AUTHOR]

In a heavy ion fusion driver, arrays of superconducting quadrupoles will transport parallel beams through a sequence of induction acceleration cells. The development of such arrays is a unique and challenging task. Since magnetic transport is one of the most expensive subsystems, economy of fabrication is a primary consideration. A compact design is essential to limit the size and cost of induction cores. Special edge coils have to be implemented to adjust the field in outer cells and terminate the magnetic flux. The development of superconducting magnets for both near term experiments and the ultimate driver application is actively pursued by the U.S. Heavy Ion Fusion Program. The main parameters and requirements are discussed, and the R&D status and plans are presented. [ABSTRACT FROM AUTHOR]

Four NbTi superconducting prototype quadrupole magnets have been built for the High Current Transport Experiment (HCX) as part of the multi-beam heavy-ion fusion research activity, led by the Lawrence Berkeley National Laboratory (LBNL). MIT performed quench training and ramp rate tests of the two prototype magnets that were designed and built by the Advanced Magnet Lab, Inc. (AML), based on a novel concept featuring cable-in-groove and multi-layer stacking. Both magnets are splice-free without inter-layer or inter-quadrant joint. Each coil was wound with a continuous NbTi round cable, placed in precise grooves machined in G-11 plates. The two magnets differ in their cable construction and their coil and yoke configuration. Each magnet was tested more than once in liquid helium bath with a room temperature thermal cycle between cold tests. This paper describes the results of the performance tests as well as the instrumentation and the quench protection system. Possible improvements for future coil winding are discussed. [ABSTRACT FROM AUTHOR]

The effect of a residue from wine industry was investigated as a corrosion inhibitor for API P110 steel in hydrochloric acid. The extract was characterized using Fourier-transform infrared spectroscopy (FTIR), hydrogen nuclear magnetic resonance (1H NMR) and chromatography. The influence of temperature (303–333 K) and grape peel extract concentration were studied using gravimetric and electrochemical experiments. The coupon surfaces were evaluated using microscopy techniques, FTIR-ATR and the contact angle. The by-product exhibited high weight loss efficiencies at 303 K with 4.0 g/L of the extract (83.81%) even after storage. The inhibition increased with the addition of an inorganic enhancer, indicating a synergistic effect between the active compounds and maximum efficiency of 94.48%. Polarization tests indicated that the inhibitor adsorbs on anodic and cathodic regions. The surface characterization techniques confirmed the formation of an organic film and a less attacked surface was observed for the inhibited system. Image 1 • A residue from wine industry was evaluated as a corrosion inhibitor. • The microencapsulated inhibitor showed weight loss efficiency up to 83.81%. • The mechanism was both physical adsorption and electrostatic interactions. • The synergism of blends was verified by weight loss and electrochemical tests. • Contact angle analysis indicated that the inhibitory film was hydrophobic. [ABSTRACT FROM AUTHOR]

Although there are many antiviral drugs available for the treatment of herpes simplex virus (HSV) infections, still the synthesis of new anti-HSV candidates is an important strategy to be pursued, due to the emergency of resistant HSV strains mainly in human immunodeficiency virus (HIV) co-infected patients. Some 1,4-dihydro-4-oxoquinolines, such as PNU-183792 (1), show a broad spectrum antiviral activity against human herpes viruses, inhibiting the viral DNA polymerase (POL) without affecting the human POLs. Thus, on an ongoing antiviral research project, our group has synthesized ribonucleosides containing the 1,4-dihydro-4-oxoquinoline (quinolone) heterocyclic moiety, such as the 6-Cl derivative (2), which is a dual antiviral agent (HSV-1 and HIV-1). Molecular dynamics simulations of the complexes of 1 and 2 with the HSV-1 POL suggest that structural modifications of 2 should increase its experimental anti-HSV-1 activity, since its ribosyl and carboxyl groups are highly hydrophilic to interact with a hydrophobic pocket of this enzyme. Therefore, in this work, comparative molecular docking simulations of 1 and three new synthesized oxoquinoline-acylhydrazone HIV-1 inhibitors (3-5), which do not contain those hydrophilic groups, were carried out, in order to access these modifications in the proposition of new potential anti-HSV-1 agents, but maintaining the anti-HIV-1 activity. Among the docked compounds, the oxoquinoline-acylhydrazone 3 is the best candidate for an anti-HSV-1 agent, and, in addition, it showed anti-HIV-1 activity (EC50 = 3.4 ± 0.3 μM). Compounds 2 and 3 were used as templates in the design of four new oxoquinoline-acylhydrazones (6-9) as potential anti-HSV-1 agents to increase the antiviral activity of 2. Among the docked compounds, oxoquinoline-acylhydrazone 7 was selected as the best candidate for further development of dual anti-HIV/HSV activity. [ABSTRACT FROM AUTHOR]