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This paper investigates the boosting effect on friction reduction performance of a fatty triamine (AM) when used as a third organic additive to base oil containing molybdenum-based additives and ZDDP for different tribopairs. The addition of the AM gives an unreached friction level under boundary lubrication with organic molybdate and ZDDP for steel. The structure of the tribofilm obtained with ternary mixture composed of stoichiometric MoS 2 long sheets located on top surface and aligned in the sliding direction could be at the origin of this remarkable behavior. Finally, a tribochemical action mechanism is proposed to describe the functionality of AM in boosting the formation of long MoS 2 lamellar sheets. [ABSTRACT FROM AUTHOR]

In cremation rituals in the Netherlands, music plays an important role. However, what exactly this role is remains unclear. In the literature on cremation rituals, music has received little attention up to now. A computational analysis of music played during cremations and a subsequent comparison of the results of this analysis with results of the analysis of two other playlists containing popular music shows that the crematorium playlist differs significantly from the other two playlists. The music played at cremations does indeed have specific properties, properties that correspond to notions typically expected at cremations, making it suitable for the occasion. Theories of the relation between musical properties and emotions indicate that the music played as part of cremation rituals can be qualified as serene, solemn and tender. Here, we provide computational evidence that this is indeed the case. [ABSTRACT FROM AUTHOR]

Fig. S1. Schematic to accompany the paper (optional graphical abstract). [Display omitted] • A method was validated for polymer mass concentrations in human whole blood. • Polymers from plastics were detected and quantified in human blood. • Polymers in human blood represent several high production volume plastics. • Blood donors were from general public. • Quality control of background plastic throughout sampling and analysis is key. Plastic particles are ubiquitous pollutants in the living environment and food chain but no study to date has reported on the internal exposure of plastic particles in human blood. This study's goal was to develop a robust and sensitive sampling and analytical method with double shot pyrolysis - gas chromatography/mass spectrometry and apply it to measure plastic particles ≥700 nm in human whole blood from 22 healthy volunteers. Four high production volume polymers applied in plastic were identified and quantified for the first time in blood. Polyethylene terephthalate, polyethylene and polymers of styrene (a sum parameter of polystyrene, expanded polystyrene, acetonitrile butadiene styrene etc.) were the most widely encountered, followed by poly(methyl methacrylate). Polypropylene was analysed but values were under the limits of quantification. In this study of a small set of donors, the mean of the sum quantifiable concentration of plastic particles in blood was 1.6 µg/ml, showing a first measurement of the mass concentration of the polymeric component of plastic in human blood. This pioneering human biomonitoring study demonstrated that plastic particles are bioavailable for uptake into the human bloodstream. An understanding of the exposure of these substances in humans and the associated hazard of such exposure is needed to determine whether or not plastic particle exposure is a public health risk. [ABSTRACT FROM AUTHOR]

Highlights: [•] The spent C300 adsorbent can be regenerated by washing with alcohols. [•] Initial adsorption capacity of the fresh C300 can be recovered after regeneration with methanol. [•] After three desulfurization–regeneration cycles the adsorption capacity remain constant. [ABSTRACT FROM AUTHOR]

Abstract: The Metal Organic Framework (MOF) C300 system was used as a sorbent of benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (DMDBT) from simulated diesel fuel at constant temperature (304K) and initial sulfur concentration (1724ppm). Once thermodynamic equilibrium had been reached, thermal regeneration under inert flow within the temperature range 373–473K was attempted and a second adsorption isotherm was recorded under exactly the same experimental conditions as the previous one. Regeneration at 473K for all studied organosulfur compounds was only partial as shown by the lower level of adsorption regarding the fresh C300 sorbent. The recovered adsorption capacity was found to be a function of the boiling point of the three adsorbates, which means that the protocol employed to desorb the organosulfur compound (473K, inert flow) allows only a fraction of the adsorbed phase to be desorbed, smaller for the S-containing molecules with a higher boiling point compound. In addition, it has been observed that the adsorption capacity recovered after the first cycle is maintained for further regeneration cycles. Adsorption of the sulfur compound is very strong, as shown by the slight drop in crystallinity and by the observation of a certain fraction of oxidized species (S(VI) moieties), as confirmed by the photoelectron spectra of the regenerated sorbent. [Copyright &y& Elsevier]

Abstract: Adsorption of organo-sulfur compounds present in liquid fuels on metal–organic framework (MOF) compounds is an efficient alternative to the conventional hydrodesulfurization process. It has been demonstrated that the extent of dibenzothiophene (DBT) adsorption at temperatures close to ambient (304K) is much higher on MOFs systems than on the benchmarked Y-type zeolite. In addition, the DBT adsorption capacity depends strongly on the MOF type as illustrated by the much higher extent of adsorption observed on the copper- (C300) and Al-containing (A100) MOF systems than on the Fe-containing (F300) MOF counterpart. With the aim to investigate the operation in consecutive cycles, the MOFs used in adsorption experiments were regenerated. In addition, the remaining S-containing compounds were identified and quantified by photoelectron spectroscopy (XPS). Examination of S2p core-level spectrum of the adsorbed S-compounds of regenerated MOFs pointed out that a fraction of these molecules become oxidized into S(VI) species. [ABSTRACT FROM AUTHOR]

Abstract: The surface of sulfonic acid functionalized silica has been modified by silylation, using two silylating agents: (CH3)3SiCl and CF3(CF2)5(CH2)2Si(CH3)2Cl. The modified supports were characterized by different techniques. For these systems, BET specific area was found to decrease upon silylation, but the effect on other textural properties depends on the silylating agent used. Once modified the supports were taken to prepare catalysts by ionic exchange with a palladium salt. The palladium species ratio depends on the used support. Catalyst system of supported palladium nanoparticles deposited on HSO3-functionalized commercial silica produces hydrogen peroxide with a high yield by feeding a non-flammable H2/O2 mixture into a non-acidic catalyst-methanol suspension at 313K. However, catalysts prepared with silylated supports show a low yield to hydrogen peroxide, due to low H2O2 selectivity. The drop in the selectivity to hydrogen peroxide is related with the different proportion of palladium species present in silylated catalysts as compared to non-silyled sample. [ABSTRACT FROM AUTHOR]

Abstract: The surface of a Ti/SiO2 catalyst was silylated using hexamethyldisilazane (HMDS) and tetramethyldisilazane (TMDS) as silylating reagents in vapor phase. The silylation of silanol (Si–OH) on the catalysts was confirmed by diffuse reflectance UV–vis, DRIFT spectroscopy and solid-state 29Si MAS NMR techniques. Titanium-containing mesoporous amorphous silica has been successfully modified by trimethylsilylation enhances its hydrophobicity producing an increase in the hydrogen peroxide efficiency and in selectivity to epoxide in the epoxidation of alkenes with H2O2. These effects are more evident when the hydrogen peroxide concentration is higher. As the results show the silylation degree reached is higher when TMDS is employed, showing the catalysts silylated with TMDS a better hydrogen peroxide efficiency and selectivity to epoxide. [ABSTRACT FROM AUTHOR]

Abstract: In this communication, we describe p-xylene oxidation with molecular oxygen at 373K and atmospheric pressure using N-hydroxyimide catalysts. p-Xylene conversion was rather high over the first 2h of reaction and complete by the end of the experiment. The product distribution curves versus reaction time are typical of consecutive reactions. The main intermediate product is p-toluic acid. Peak concentration and the shape of its concentration profile depend heavily on the N-hydroxyimide catalyst used. This effect seems to be related to the NO–H bond dissociation energy (BDE) of the N-hydroxyimides employed. [ABSTRACT FROM AUTHOR]

Recently, evidence has emerged for a radial orientation bias in early visual cortex. These results predict that in early visual cortex a tangential bias should be present for motion direction. We tested this prediction in a human imaging study, using a translating random dot pattern that slowly rotated its motion direction 360° in cycles of 54 s. In addition, polar angle and eccentricity mapping were performed. This allowed the measurement of the BOLD response across the visual representations of the different retinotopic areas. We found that, in V1, V2, and V3, BOLD responses were consistently enhanced for centrifugal and centripetal motion, relative to tangential motion. The relative magnitude of the centrifugal and centripetal response biases changed with visual eccentricity. We found no motion direction biases in MT+. These results are in line with previously observed anisotropies in motion sensitivity across the visual field. However, the observation of radial motion biases in early visual cortex is surprising considering the evidence for a radial orientation bias. An additional experiment was performed to resolve this apparent conflict in results. The additional experiment revealed that the observed motion direction biases most likely originate from anisotropies in long range horizontal connections within visual cortex. Hum Brain Mapp, 2009. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Perfluorooctanoic acid (PFOA) is a perfluorinated compound ubiquitously detected in the environment, including wildlife and humans. Despite the available information, research on the cytotoxicity of PFOA in non-tumoral mammalian cells is relatively limited. In this work, two in vitro toxicity systems were employed to provide further insight into the cytotoxic and mutagenic potential of PFOA. The cytotoxicity of the chemical towards Vero cells was assessed using biochemical and morphological parameters, while mutagenicity was evaluated according to Ames test. High doses of PFOA cause oxidative stress in Vero cells, that was closely linked to cell cycle arrest at the G1 phase and induction of apoptosis. Our results corroborate previous findings in human tumoral cells and suggest that the mode of action of this perfluorinated compound is not a peculiarity among mammalian cell types. On the other hand, the compound was not mutagenic in the Ames test, using four strains of Salmonella typhimurium in the presence or absence of rat S9 metabolic activation system. [Copyright &y& Elsevier]

Abstract: Wear particles found in ultra-low wear rate experiments were analyzed in order to understand the wear mechanism. Using a sophisticated particle separation method, the debris were separated from the oil and then analyzed using transmission electron microscopy accompanied by electron diffraction for chemical characterization. The majority of the wear particles have a size of about 250 nm, only very few are larger than 1  m. The particles appear mostly amorphous and contain chemical elements of both interacting solids as well as the oil. In addition, almost all particles have a thickness of 30 nm or less. The proposed particle generation mechanism is a squeezing process of flowed material under pressure. [Copyright &y& Elsevier]

Abstract: This work describes the influence of quaternary ammonium compounds [(R4N)+X−] in the yield of ethylbenzene hydroperoxide (EBHP) during the liquid-phase oxidation of ethylbenzene (EB) with molecular oxygen. Reaction rates were affected not only by the type of R4N+ and X− ions but also by their concentrations in the reaction medium. In the presence of structurally different quaternary ammonium bromide salts, ethylbenzene conversion increased because the ammonium salt favors the interaction with the EBHP. The type of the X− anion also modified the time-course of the EBHP and EB conversion profiles, although this effect was less notorious in the former; the highest EBHP concentration was reached with tetramethylammonium iodide and the lowest one with the hydroxide salt. Both EB conversion and EBHP yield decreased strongly upon reducing the concentration of the catalyst from 10−3 to 10−4 M and this effect was even more marked for the iodide salt than for the bromide counterpart. [Copyright &y& Elsevier]

Abstract: A series of titanium–silica catalysts was prepared by grafting a titanium isopropoxide precursor on amorphous silica substrates with BET areas of 162–709 m2 g−1 and pore volumes of 0.5–1.4 mL g−1. The grafting process, consisting of hydrolysis of the Ti precursor by the hydroxyl groups of the silica surface, yielded catalysts containing Ti loadings of 0.65–2.37 wt%. The textural properties of the Ti/SiO2 catalysts were evaluated from the nitrogen adsorption–desorption isotherms, and their surface species were studied by ultraviolet–visible (UV–vis) spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and X-ray photoelectron spectroscopy (XPS) techniques. These catalysts were tested in the liquid phase epoxidation of oct-1-ene with hydrogen peroxide as a model reaction. All catalysts showed very high (95–98%) hydrogen peroxide consumption at 353 K after 1 h reaction time, but selectivity to the epoxide was strongly dependent on the pore volume of the silica substrate. Under these reaction conditions, an epoxide selectivity as high as 90–93% was reached on the catalysts with the largest pore volumes (1.4 mL g−1). Spectroscopic techniques also revealed that TiIV ions coordinated tetrahedrally by oxide ions are essential to obtaining highly selective catalysts in the reaction. [Copyright &y& Elsevier]

Abstract: The spatio-temporal requirements for direction selectivity were studied in two extrastriate motion processing areas in the cat, area 18 and the posteromedial lateral suprasylvian cortex (PMLS). Direction, velocity and pixel size of random pixel arrays (RPA) were adjusted for each neuron and direction selectivity was measured as a function of step size and delay for a given optimal velocity. A subset of direction selective complex cells in area 18 was tuned to intermediate step size and delay combinations rather than the smoothest motion (band-pass cells). Other area 18 complex cells responded best to the smallest value of step size and delay (low-pass cells). Tuning varied with the pixel size of the RPA. Cells with tuning for smaller pixels favoured a preference for non-smooth motion. Area 18 cells with lower spatial resolution showed larger optimal and maximal step sizes. For a subset of the cells in area 18, we measured direction selectivity for extensive step-delay combinations, covering multiple velocities. Results showed that most cells were tuned to narrow range of step-delay combinations, and that the optimal step size was independent of temporal delay. Direction selective complex cells in PMLS were tuned to larger pixel sizes than those in area 18, although the distributions did overlap. In contrast to area 18, PMLS cells preferred the smoothest motion, irrespective of RPA pixel size. [Copyright &y& Elsevier]

Abstract: Friction-reducing properties of MoDTC-containing lubricants have been investigated as a function of their oxidative degradation state. The oxidation test is conducted with oxygen and nitrogen oxide gases simulating aged engine oils during service. The main oxidation effect is to decrease the concentrations of MoDTC and other additives present in the formulation. However, when the ZnDTP concentration is reduced in the lubricant, MoDTC is not so fast consumed because of the formation of less stable MoDTP compound by acid–base reaction is inhibited. The decrease of friction reduction properties appears significant when about 80% of additives content has been consumed by oxidation. The friction reduction mechanism of MoDTC is due to the formation of MoS2 single sheets during the tribochemical reaction. When the concentration of MoDTC decreases in the lubricant due to oxidation, MoS2 sheets are found to be modified both in size, number, shape and chemical composition. Final, at very low MoDTC concentration, sheets cannot grow to a sufficient size to cover the asperities for efficient friction reduction. [Copyright &y& Elsevier]

Abstract: Fuel economy and reduction of harmful elements in lubricants are becoming important issues in the automotive industry. An approach to respond to these requirements is the potential use of low friction coatings in engine components exposed to boundary lubrication conditions. Diamond-like-carbon (DLC) coatings present a wide range of tribological behavior, including friction coefficients in ultra-high vacuum below 0.02. The engine oil environment which provides similar favourable air free conditions might lead to such low friction levels. In this work, the friction and wear properties of DLC coatings in boundary lubrication conditions have been investigated as a function of the hydrogen content in the carbon coating. Their interaction with ZDDP which is the exclusive antiwear agent in most automotive lubrication blends and friction-modifier additive MoDTC has been studied. Hydrogenated DLC coatings can be better lubricated in the presence of the friction-modifier additive MoDTC through the formation of MoS2 solid lubricant material than can non-hydrogenated DLC. In contrast, the antiwear additive ZDDP does not significantly affect the wear behavior of DLC coatings. The good tribological performances of the DLC coatings suggest that they can contribute to reduce friction and wear in the engine, and so permit the significant decrease of additive concentration. [Copyright &y& Elsevier]

Abstract: Barium compounds (barium oxide, barium acetylacetonate, barium nitrate) have been used as catalysts for the liquid-phase oxidation of ethylbenzene with molecular oxygen. Ethylbenzene hydroperoxide (EBHP) was the major product, although small amounts of acetophenone (ACP) and 1-phenylethanol were also formed, indicating that C–H bond activation takes place only at the alkyl chain. For barium oxide, the rate of EBHP formation was found to increase with the barium concentration up to 1ppm Ba, thereafter decreasing at higher concentrations. The type of barium compound influenced the rate of EBHP formation to a significant extent. As a general rule, non-basic barium salts, such as nitrate and acetylacetonate, led to a decrease in the EBHP yield and also to a decrease in ethylbenzene conversion; although in the latter case it was less marked. This finding can be interpreted as being due to the partial decomposition of EBHP, under the experimental conditions employed in the present work, into ACP and 1-phenylethanol. [Copyright &y& Elsevier]

Polyphenol oxidase (PPO) (EC.1.14.18.1) activity has been shown to be related to time-dependent discoloration of Asian noodles. Our objective was to determine the impact of divergent selection for PPO activity on agronomic, milling, bread baking, and Chinese raw noodle quality traits in winter wheat (Triticum aestivum L.) populations. Progeny from seven winter wheat populations were selected for high or low PPO activity by the L-3,4-dihydroxyphenylalanine (L-DOPA) assay on whole kernel meal on the basis of a single replication with equal number of high and low lines in each population. The selected lines were evaluated in replicated trials in multiple environments. Agronomic, milling, bread baking, and Chinese raw noodle traits were measured for all entries. The high versus low PPO classification was confirmed from replicated trials with no overlap between low and high PPO lines for any of the populations. Divergent selection had no impact on agronomic traits except for heading date where low PPO lines averaged 1 d later to head than high PPO lines, flour ash averaged 0.11 g kg-1 higher for low compared with high PPO lines, but flour protein and flour yield did not differ between groups. The low PPO selection group had weaker dough, as reflected by lower mixograph tolerance, and lower crumb grain scores. Chinese raw noodle texture was altered by divergent selection so that the low PPO group produced noodles that were less elastic, sticky, and chewy than the high PPO group. Chinese raw noodles became darker (lower L*), more yellow (greater b*), and more red (greater a*) with time. Low PPO lines averaged less change in L* (8.9 vs. 9.6) but more change in b* (-7.70 vs. -7.02) and a* (-0.74 vs. -0.62) than high PPO lines over 24 h. Whether these changes in noodle color and texture are desirable may depend on the type of noodle and regional and personal preferences. [ABSTRACT FROM AUTHOR]

We studied the low-level interactions between motion coherence detection and binocular correlation detection. It is well-established that e.g. depth information from motion parallax and from binocular disparities is effectively integrated. The question we aimed to answer is whether such interactions also exist at the very first correlation level that both mechanisms might have in common. First we quantitatively compared motion coherence detection and binocular correlation detection using similar stimuli (random pixels arrays, RPAs) and the same noise masking paradigm (luminance signal to noise ratio, LSNR). This showed that human observers are much more sensitive to motion than to binocular correlation. Adding noise therefore has a much stronger effect on binocular correlation than on motion detection.Next we manipulated the shape of the stimulus aperture to equalize LSNR thresholds for motion and binocular correlation. Motion sensitivity could be progressively reduced by shortening the length of the motion path, while keeping the aperture area constant. Changing the shape of the aperture did not affect binocular correlation sensitivity. A `balanced'' stimulus, one with equal strengths of motion and binocular correlation signals was then used to study the mutual interactions. In accordance with previous results, motion was found to greatly facilitate binocular correlation. Binocular correlation, however did not facilitate motion detection. We conclude that interactions are asymmetrical; fronto-parallel motion is primarily detected monocularly and this information can then be used to facilitate binocular correlation, but binocular correlation cannot improve motion sensitivity. [Copyright &y& Elsevier]

Aims: Waiting time for radiotherapy is a major problem in radiation oncology practice. The aim of this paper is to present the experience of the Peter MacCallum Cancer Centre in trialling a number of strategies to reduce patient waiting times.Materials and methods: All patients starting megavoltage radiotherapy with curative intent in three separate 1-week blocks had their waiting times recorded. The cohorts were each 8 weeks apart and were before (September), during (November) and after (January) the introduction of a priority points system.Results: Median waiting time was 35 days in September, 42 days in November and 31 days in January. The number of extremely long waits (>90 days) decreased to 1 by January. Significantly more patients were pre-booked for treatment in January (27/51) compared with September (17/65; P=0.003) and November (12/65; P<0.001). Pre-booked patients had shorter waiting times compared with patients who was not pre-booked (P<0.0001). Difficulties at one particular treating location contributed to the longer median waiting times in November. Although there had no significant difference in waiting time in non-breast unit patients between the three cohorts, there was a decrease in waiting times in breast unit patients, especially between November and January (P=0.0008). There was no significant increase in delay to starting treatment in other treating units, resulting in more equitable access across all units.Conclusions: A combination of encouraging pre-booking and the introduction of a priority points system has led to a decrease in waiting times, especially among breast unit patients. [Copyright &y& Elsevier]

Different methods (EFTEM, XPS, XANES, and ToF-SIMS) are used to determine particles size and detailed chemical composition of overbased calcium alkyl benzene sulfonate (OCABS) micelles. Colloids are obtained by carbonation of calcium hydroxide in hydrocarbon phase used in lubricant in the presence of ABS surfactant. The reaction leads to well-defined nanoparticles. This paper describes the location in the nanoparticle of expected molecular species and the quantity of each species. The originality of this study is to show the presence of residual calcium hydroxide in overbased detergents. As calcium carbonate has a highly amorphous character despite a local order close to calcite one, calcium hydroxide is suspected to be present in the core even at the end of the reaction. Its quantity and location are determined by the complementarities of these surface analysis techniques. [Copyright &y& Elsevier]

Bread baking is the primary end-use criterion used to select hard spring wheat (Triticum aestivum L.) genotypes for the northwestern USA, yet the use of hard wheats has expanded beyond traditional pan breads to include Asian noodles. We assessed the relative influence of genotype, N management, and location on quality characteristics of a set of spring wheat cultivars that provided a range in gluten strength and acceptability for bread and Asian noodle quality, and determined whether grain characteristics could predict bread and/or noodle market suitability. Seven spring cultivars were grown at four locations across 3 yr with two levels of N fertilizer in irrigated and moisturelimited conditions. Bread quality, alkaline noodle color, and Chinese noodle color and texture were assessed on grain samples. Cultivar was the most important determinant of bread and noodle quality traits in both the irrigated and moisture-limited environments. Nitrogen level influenced only Chinese noodle color in irrigated environments, but impacted test weight, flour ash, loaf volume, and bake absorption in moisture-limited environments. Responses to N management and location were usually not cultivar specific, as interactions were not important relative to main effects of cultivar and location. Grain protein had more value than test weight or grain hardness in predicting bread and noodle quality, and was most useful in predicting loaf volume and Chinese noodle color characteristics. Cultivar selection is critical for achieving a desired end use, with location effects being of secondary importance. Nitrogen management for a particular end use will be difficult, with N level being much less important than cultivar selection and location. Grain protein may be the best predictor of the suitability of a particular cultivar produced in a specific year for alternative end-use possibilities, with high-protein grain most suitable for bread production and low-protein, high-quality grain more suitable for noodle production. [ABSTRACT FROM AUTHOR]

The characterization of tribofilms has already been studied by various surface analysis tools for many years. The analytical techniques usually performed on this kind of samples are X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and X-ray absorption near-edge structure (XANES). XPS is interesting for chemical environment information. AES has a good spatial resolution (approx. 0.5 μm) permitting AES mapping or making AES linescans. With XANES, the polyphosphate chain length can be characterized in case of ZDDP tribofilm. AES and XPS depth profiles can also be performed in order to follow the composition of the tribofilm with depth. Therefore, coupling XPS, AES and XANES is interesting to clarify the different layer composition of the tribofilm. In this work, AES, XPS, secondary ion mass spectroscopy (SIMS) and transmission electron microscopy (TEM) are carried out on tribofilm made by ZDDP additives. By a SIMS analysis, information on the elemental distribution in the surface near layers can be obtained with high lateral and high depth resolution. The use of a time-of-flight (ToF) analyser allows to obtain information on all elements quasi-simultaneously resulting in a very high sensitivity. Our aim is to investigate the tribofilm in its depth and the interface tribofilm/substrate by using a multi-technique approach on the same ZDDP tribofilm. First, depth profiles (by AES XPS and SIMS) were carried out. Secondly, a transverse section made by focused ion beam (FIB) was evaluated by TEM. All results are discussed in order to give a better understanding of the tribofilm composition. [Copyright &y& Elsevier]

A series of titanium-silica catalysts with relatively low Ti contents were prepared by dispersing titanium isopropoxide in a solvent (cyclohexanol, 1-phenylethanol, 1-hexanol, 2-(2-ethoxyethoxy)ethanol, diglyme, and acetophenone) and then mixing each solution with the silica substrate. The process consisting of the hydrolysis of the Ti precursor by the hydroxyl groups of the silica surface yielded catalysts containing Ti loadings of 0.8–3.0 wt%. The catalysts prepared were characterized using various spectroscopic techniques, including diffuse reflectance infrared Fourier transform (DRIFTS), ultraviolet–visible (UV–vis), and photoelectron (XPS) spectroscopic techniques. The catalytic activity of the catalysts studied was determined using liquid-phase epoxidation of 1-octene with hydrogen peroxide as a model reaction. All catalysts showed very high hydrogen peroxide consumption but the selectivity to the epoxide was seen to be strongly dependent upon the solvent used in the preparation. Only the catalyst prepared using cyclohexanol solvent, in which the titanium content was low (0.8 wt%) and the Ti(IV) ions were isolated tetrahedrally coordinated by oxide anions, exhibited very high (95%) selectivity to the epoxide. The other Ti/SiO2 catalysts containing a higher amount of titanium (1.0–3.0 wt%), but less disperse and with Ti(IV) in an octahedral environment, exhibited poor performance in the target reaction. [Copyright &y& Elsevier]

Ti-containing MFI (TS-1) samples were synthesized and then modified with small amounts (0.3–1.7 wt.%) of alkali, alkaline-earth and lanthanide ions. UV-Vis reflectance spectra for all the samples revealed absorption at 215 nm, due to the O2−→Ti4+ charge transfer transition of tetrahedrally coordinated titanium incorporated into the silicalite framework. Similarly, the binding energy of the Ti 2p3/2 core-level for all the M/TS-1 samples appeared at ca. 460.0 eV, which is also indicative of Ti(IV) coordinated to oxide anions in a tetrahedral symmetry. The catalysts were tested in the epoxidation reaction of 1-octene, using aqueous hydrogen peroxide as an oxidant agent at 353 K. The conversion of hydrogen peroxide was slightly lower for the M/TS-1 samples than for the titanium-silicalite-1 (TS-1) reference and selectivity to epoxide was higher when the metal cation (Mn+) was added. A good correlation between the formation of secondary reaction products in the 1-octene epoxidation and Brønsted acid sites (measured by the infrared spectra of adsorbed deuterated acetonitrile) was found. This finding is explained as being due to the neutralization of the surface acidity of the TS-1 zeolite by the metal oxide (MO) incorporated, with the subsequent inhibition of the solvolysis reactions of the epoxide on the acid sites. [Copyright &y& Elsevier]

Using a unique technique, we formed a thin layer of ice on steel surface at temperature as low as 123 K in an ultra-high vacuum. We investigated the frictional behavior of such a thin ice layer in the same UHV using a pin-on-disk friction tester. The sample surfaces were monitored in situ using X-ray Photoelectron Spectroscopy (XPS). Testing data showed that the friction coefficient was a linear function of temperature. This study indicates that the sliding motion is lubricated by a frictionally melted liquid layer. [Copyright &y& Elsevier]

The preparation, some characterizations, and the reactivity of the homogeneous complex of Mo(VI) with 4,6-dimethyl-2-mercaptopyrimidine ligand (DMMP) were carried out. Elemental analysis, Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) revealed that Mo(VI) becomes coordinated with two DMMP molecules. The resulting complex was found to be highly effective in 1-octene epoxidation with ethylbenzene hydroperoxide (EBHP) in liquid phase. This complex was soluble in the reaction media and its catalytic activity proved to be lower than that of MoO2(acac)2, although its solubility rate in the reaction media was somewhat slower. This drawback was avoided by adding the complex dissolved in ethanol. In this case, the catalysts appeared to be highly active and selective in the target reaction when working at 367 K. [Copyright &y& Elsevier]

Examines the development of resistant wheat cultivars to Wheat streak mosaic virus (WSMV). Comparison of transgenic and classical sources of resistance to WSMV; Evaluation of the three sets of germplasm; Inclusion of adapted cultivars with various level of tolerance.

Determines the influence of genetic variation in the grain quality of hard red spring wheat. Measurement of grain hardness by near-infrared reflectance; Results of the single-kernel characterization system; Varieties deemed the most suitable for milling and baking purposes.

Uses the Reagan administration, with over 800 Senate confirmed appointments, to examine patterns found in previous studies of presidential appointees. Continued pattern of `in-and-outers'; Partisan factors; Growing undesirability associated with high-level posts; Low salaries and a need to comply with ethics laws; More appointees being drawn from Washington community; Women do not fare well.

Presents an electrical characterization of discrete Bipolar Junction Transistor (BJT) devices with nonuniform doped emitter and base zones, with reference to an experiment conducted. Methodology employed to conduct the experiment; Information on bipolar junction transistors; Results of the experiment.

Presents information on a study which investigated the distribution of nitrates in the Mediterranean Sea. Use of an inverse model in tests; Methodology used in the study; Environmental characteristics of the Mediterranean; What the study revealed.

Provides a new evaluation of the discharge of river water and solids, major ions, organic carbon, and nutrients from the Eurasian land mass into the Arctic Ocean. Description of the Eurasian drainage basin of the Arctic Ocean and the specificity of its climate and geology; Water and suspended-sediment discharge into the Eurasian Arctic seas.

Demonstrates in computer simulations how the visual system in the brain can perform both sharp segregation and global integration of motion signals. The excitatory interactions between different directions being sharply tuned while inhibitory interactions are broadly tuned; The prediction of adaptation to simultaneous motion in opposite directions; The occurrence of an orthogonal motion after-effect.

This article focuses on a research paper written by E.K. Franseen and C. Mankiewicz which describes Miocene carbonate depositional sequences at Las Negras and Nijar in Spain. The stratigraphy at Las Negras and Nijar is similar to that of the Sorbas Basin. Consequently details of the Sorbas Basin sequence can be used both to augment and to test interpretations of the Almeria Basin sections. At Las Negras Franseen and Mankiewicz identify two horizons of coral blocks at the bases of which they place the lower boundaries of their Depositional Sequences 2 and 3 respectively. In the Sorbas Basin however identical reef blocks occur at different heights in the stratigraphic column and are not concentrated at two levels. Franseen and Mankiewicz suggest correlation between Almeria Basin sequences and those of the Almanzora Corridor, north of Sorbas Basin.

A letter to the editor is presented which discusses a study regarding the role of telomere for melanoma spontaneous regression.

[Display omitted] • A grain size of ∼ 1 µm was measured by EBSD for He atomized NdFeB powders. • Elongated grains grow from nucleation sites forming radial colonies. • Optimum annealing at 700 ˚C increased the BH max in > 25 %. • No significant grain growth observed after annealing up to 1050 ˚C. • Bonded magnets from novel composition NdFeB gas atomized powders could cover a market niche. New compositions of Nd-Fe-B powders were produced via gas atomization. Helium and argon were used as atomizing gases. For the same process parameters, helium resulted in a powder that is 6 times finer than the powder produced with argon. In both cases, the atomization conditions were set to achieve fine powders and, therefore, fine microstructures, since this is critical to obtain a suitable coercivity. The powders were sieved to separate the fraction below 20 μm (∼90 % of powder atomized with He). The microstructure is formed by a mix of elongated and equiaxial grains with random crystallographic orientation and an average grain size of ∼ 1 μm, which was measured by Electron Backscattered Diffraction. This kind of measurements and images were taken for the first time for fine helium atomized Nd-Fe-B powders. The embedding of the powder in copper was found to be useful, as the conventional mounting in metallographic conductive resin produced charging of the sample. Annealing up to 1000 °C did not cause any significant grain growth that could deteriorate the magnetic properties. Annealing at 700 °C for 15 min improved the magnetic properties due to the crystallization of residual amorphous phase. Warm compaction was used to produce magnets with a high volume fraction of magnetic powder (>70 %) and low real porosity (∼5 %). These magnets exhibit a high remanence (∼0.5 T) and maximum energy product (∼35 kJ/m3), combined with a suitable intrinsic coercivity (>500 kA/m). The new compositions and processing route could cover a market niche. The thoroughly analyzed powders could be also suitable for some additive manufacturing technologies that require spherical powders with very specific particle size distributions. [ABSTRACT FROM AUTHOR]

The PROFIT study was designed to evaluate hypofractionated (HF) radiotherapy versus conventional fractionation (CF) for patients with intermediate-risk prostate cancer (IR-PCa). Similar efficacy and toxicity outcomes were previously reported. Here the long-term patient-reported outcomes (PROs) following treatment are presented. A total of 1206 men with IR-PCa were randomized to receive 78 Gy in 39 fractions over 8 weeks (CF) or 60 Gy in 20 fractions over 4 weeks (HF). PROs were evaluated at baseline, 24 and 48 months using the Expanded Prostate Cancer Index Composite (EPIC), American Urological Association Symptom Score (AUASS), and the 12-item Short Form Health Survey (SF-12) which combine 2 parts: a physical component summary (PCS) and a mental component summary (MCS). A minimally important difference (MID) was defined as a deterioration of domain- or subdomain-specific health-related quality of life (HRQoL) score at each time point compared to baseline ≥ 0.5 standard deviation. Wilcoxon's rank sum test was used for comparing all continuous measures, and Pearson's Chi-squared test was used for comparing MID between two arms at each visit. Statistical significance was declared only when P < 0.01. Statistical analyses were performed using R version 4.3.0. At baseline, 87.9% of patients in the CF and 88.5% in the HF arm provided completed forms dropping to 76.5% and 77.9% at 48 months, respectively. AUASS was similar and stable (median of 5) over time in both arms (P > 0.2). No significant differences were found between the two arms in the urinary, bowel, sexual and hormonal domains or subdomains at any time point (P > 0.02). The greatest decline over time occurred in sexual domain, decreasing ≥ 10 points from baseline to 24 months in both arms. SF-12 means of both, PSC and MSC, were similar and remained stable at all time points. At 24 months, MSC summary was significantly higher in CF arm (46 in CF arm vs 45 in HF arm; P = 0.005), but not maintained at 48 months. The proportion of patients reporting MID was similar in both arms across all scores except in the bowel function at 48 months, where there was a significant difference in favor to the HF arm (51.5% in CF arm vs 39.5% in HF arm; P = 0.001) and a trend in bowel summary (53.4% in CF arm vs 44% in HF arm; P = 0.01) Overall treatment satisfaction was high in both arms, ≥ 88% of patients were either satisfied or extremely satisfied with treatment. Findings from the PROFIT study suggest no differences in urinary, bowel and sexual HRQoL between CF and HF. However, the proportion of patients reporting MID in bowel function at 48 months was significantly higher in the CF arm. At 24 months SF-12 MCS were significantly higher in the CF arm but no longer present at 48 months. [ABSTRACT FROM AUTHOR]

The lubricating properties of two different organomolybdenum additives combined with ZDDP were evaluated for different tribopairs involving carbon-based coatings, hydrogenated DLC and nanocrystalline diamond NCD. Their performances were investigated using reciprocating linear tribometer and compared with the traditional additivation MoDTC/ZDDP. The highly sulfurised moly-trimer additive and organic molybdate ester additive displayed good friction reducing properties in comparison with traditional additivation MoDTC for all tribopairs tested, especially organic molybdate ester. XPS and ToF-SIMS surface analyses performed on the tribofilms formed with these different organomolybdenum additives showed the formation of MoS 2 /MoS 2− x O x species exhibiting a solid lubricant character, but preferentially on steel surfaces. HRTEM/EDS analyses confirmed the presence of MoS 2 /MoS 2− x O x sheets embedded inside an oxygen-rich amorphous matrix. This is different from the traditional additivation that leads to the polyphosphate/phosphate glass matrix. Organic molybdate ester is a sulfur- and phosphorus-free additive that appears particularly interesting for achieving low friction while minimizing the S content of the lubricant. [ABSTRACT FROM AUTHOR]