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Cold spray is a novel and promising technology to obtain surface coating. Notwithstanding the several technological advantages with respect to other processes, its diffusion is somewhat limited because of the limited knowledge on the mechanical properties of the cold sprayed materials and in particular, the fatigue behavior. Moreover, the existing data concerning fatigue behavior of coated specimens are controversial and different material system shows different behaviors. The aim of this study is to distinguish the involved parameters and their effect on fatigue behavior of cold sprayed systems. A critical discussion on four important parameters i.e. interface quality, material properties, deposition parameters and residual stress is given. The influential parameters are consolidated in one formula, which can predict the fatigue limit of cold spray system as a function of residual stress, coating hardness and stress gradient in the specimen.
The World Mental Health Survey Initiative (WMHSI) has advanced our understanding of mental disorders by providing data suitable for analysis across many countries. However, these data have not yet been fully explored from a cross-national lifespan perspective. In particular, there is a shortage of research on the relationship between mood and anxiety disorders and age across countries. In this study we used multigroup methods to model the distribution of 12-month DSM-IV/CIDI mood and anxiety disorders across the adult lifespan in relation to determinants of mental health in 10 European Union (EU) countries.
Logistic regression was used to model the odds of any mood or any anxiety disorder as a function of age, gender, marital status, urbanicity and employment using a multigroup approach (n = 35500). This allowed for the testing of specific lifespan hypotheses across participating countries.
No simple geographical pattern exists with which to describe the relationship between 12-month prevalence of mood and anxiety disorders and age. Of the adults sampled, very few aged ⩾80 years met DSM-IV diagnostic criteria for these disorders. The associations between these disorders and key sociodemographic variables were relatively homogeneous across countries after adjusting for age.
Further research is required to confirm that there are indeed stages in the lifespan where the reported prevalence of mental disorders is low, such as among younger adults in the East and older adults in the West. This project illustrates the difficulties in conducting research among different age groups simultaneously.
In the aftermath of the major earthquake that hit Pakistan in 2005, there appeared to be a paucity of psychometric tools validated in Urdu. It was decided to translate the Impact of Event Scale - Revised (IES-R) so as to obtain an internationally validated and recognised psychometric tool for use in research into post-traumatic stress disorder. The resulting Urdu and English versions of the IES-R were compared for linguistic, conceptual and scale equivalence. The Urdu version of the IES-R (UIES-R) can be used for clinical, psychological trauma populations in Pakistan with evidence of good reliability and satisfactory validity. In trauma research in Pakistan the UIES-R will be an extremely useful psychometric tool.
Intense exercise has been associated with free radical damage that forms potentially measurable by-products in the blood and muscle of exercising subjects. The extent of damage to the exercising animal has yet to be conclusively determined, and studies often focus on by-products in the blood rather than muscle. The current study examined the presence of oxidative products in the muscle of exercising horses as well as the effects of excess vitamin E on the presence of these products. Eight Thoroughbred horses were used in a crossover design, with one group being fed vitamin E at the 1989 NRC [National Research Council (1989) Nutrient Requirements of Horses. 5th revised edn.; Washington DC: National Academy Press, pp. 48] level recommended for horses in moderate to intense work (80 IU kg DM− 1), and the second group being fed the control diet plus 3000 IU day− 1dl-α-tocopheryl acetate. The horses underwent an 8-week training programme and a final standard exercise test (SET). During the SET, the horses ran on a 6° incline to exhaustion. Muscle samples were biopsied before and after performing the SET and analysed for the presence of carbonyl groups and ubiquitin. Blood was collected prior to the SET and analysed for vitamin E. No significant differences in plasma vitamin E were found between treatment groups. However, myofibril carbonylation, a product of free radical damage to muscle tissue, was found to be lower in vitamin E-supplemented horses post-SET exercise (P < 0.05), suggesting that vitamin E influences some measures of oxidative stress in exercising horses, particularly following a strenuous bout of exercise. Ubiquitin was not detected in myofibrils, indicating clearance of carbonyl groups by a different mechanism.
Exercise places an increased demand on the body's systems, both to provide fuel for working musculature and to neutralize and dispose of toxic build-up. By-products of demanding performance are reactive free radicals. Dietary consumption of vitamin E, an antioxidant, may be a plausible way to reduce free radical damage. The present study examined the effects of supplemental dietary vitamin E on the presence of oxidation products and antioxidant capacity in blood and tissue of exercising horses. Eight Thoroughbred horses were used in a crossover design study, with one group consuming a diet containing vitamin E at the 1989 National Research Council (NRC) level recommended for horses in moderate to intense work (80 IU kg DM− 1 [National Research Council (1989). Nutrient Requirements of Horses. 5th revised edn.; Washingto, DC: National Academy Press, pp. 48]), and the second group being fed the control diet plus 3000 IU day− 1dl-α-tocopheryl acetate. The horses underwent an adaptation phase, an 8-week training programme and a final standard exercise test (SET) during which the horses ran on a 6° incline to exhaustion, and then a washout phase. Horses were then crossed over to opposite treatment groups and these phases repeated. Blood samples were collected at specific points before and after exercise during the training period and before and after performing the SET. Neither plasma vitamin E nor thiobarbituric acid-reactive substance concentrations were influenced by supplemental vitamin E. Blood Trolox-equivalent antioxidant capacity values increased (P < 0.05) following 5 weeks of training in both groups, indicating improved antioxidant capacity as horses became fitter. Vitamin E supplementation did not alter plasma reduced, oxidized or total glutathione levels, nor the percentage of glutathione in the reduced form during the training period. However, vitamin E did cause an elevation in the percentage of glutathione existing in the reduced form following a SET as compared with the control diet (P < 0.006). This is possibly due to lower plasma oxidized glutathione levels in vitamin E-treated horses (P < 0.03). This study indicates that vitamin E supplementation above NRC levels can influence certain measures of oxidative stress in intensely exercising horses, and training has the ability to improve the antioxidant status of the animal.
The cytoplasm of the bacterium Thiobacillus neapolitanus contains 117 nm diameter polyhedral inclusions, “carboxysomes” (Fig. 1) that contain ribulose-1,5- bisphosphate carboxylase/oxygenase (RuBisCO). Surrounding the polyhedron are nonmembranous proteinaceous plates devoid of lipid. The carboxysomes are composed of at least 8 major peptides, all coded within the same operon. Six (CsoSIA, CsoSIB, CsoSIC, CsoS2A, CsoS2B, and CsoS3) make up the shell, and two are the large (CbbL) and small subunits (CbbS) of RuBisCO. Using immunogold labeling on ultrathin sections, peptides CsoS2A, CsoS2B, and CsoS3 have been localized to the shell. Since the original characterization of the csoSl gene, we have also immunolocalized the CsoSl peptide to the shell.
As part of our initial efforts to understand how these components are assembled into the symmetrical, functional entity, the carboxysome operon from T. neapolitanus was cloned into the pET-21a(+) plasmid, an expression vector that codes for resistance to ampicillin.
Schizotypal personality disorder (SPD) is theoretically
part of the schizophrenia spectrum both clinically and
neurobiologically. A liability for developing schizophrenia
may be associated with dysfunction of dorsolateral prefrontal
cortex (DLPFC) and its cortical and/or subcortical circuitry.
If so, abnormalities on tasks associated with DLPFC functioning
among SPD subjects would support the thesis that SPD is
neurobiologically related to schizophrenia. Antisaccade
and ocular motor delayed response performance, both of
which are ostensibly supported by DLPFC circuitry, were
assessed among 29 SPD, 17 schizophrenia, and 25 normal
subjects. Generally, the SPD subjects' performance
was more similar to normal than to schizophrenia groups.
There was evidence, however, for inhibition abnormalities
in a subgroup of SPD subjects. Antisaccade performance
identified more SPD subjects as “abnormal”
than delayed response measures.
Polychromatic synchrotron x-ray microbeams offer a very efficient alternative to electron beam methods for quantifying the amount and character of grain subdivision accompanying large deformations. With a 0.01 mm diameter collimator, bending magnet radiation from a 3.0 GeV source and image storage plates, samples of copper with thicknesses greater than 0.1 mm have been studied. Results from an as-received sample and a sample deformed to 100% torsion are compared and illustrate how efficiently grain subdivision can be quantified with polychromatic microbeam diffraction.
Many years of study have failed to establish conclusively relationships between a quasar’s spectral energy distribution (SED) and the emission lines it is thought to produce. This is at least partially due to the lack of well-observed SEDs. We present initial results from a line–SED study for a sample of 43 quasars and active galaxies for which we have optical and ultraviolet spectra and far-infrared–X-ray SEDs. We present the results of tests for correlations between line equivalent widths and SED luminosity and slope parameters and compare these results to those from earlier studies. We find that the Baldwin effect is weaker when the luminosity is defined close to the ionizing continuum of that line and conclude that the detailed SED is likely to be important in making further progress.
Thirty-six 5-month-old Dorset ram lambs (28·7 kg) were used to investigate the effects of fasting and transport on performance and selected blood parameters. Three treatment groups (no. = 12) were: (1) control-food and water, without transport; (2) fasting for 72 h, without transport; and (3) transport in a trailer to a nearby auction-barn, then driven 8 h/day for 3 days without food or water for a total of 72 h. Lambs were given a total mixed diet containing 163 g/kg crude protein throughout the 28-day post-transport period. Both fasted and transported lambs consumed less food than the control group during the first 7 days post treatment (P < 0·05). Water intake was similar for all treatment groups on the 1st day post transport, after which both fasted and transport lambs drank less ivater than control lambs during the following 6 days (P < 0·05). Live-weight loss after the 3-day fast and transport period and subsequent body-weight gain during the 28-day realimentation period differed across all treatment groups (P < 0·05 and P < 0·09; (1) 1% and 305 g, (2) 14·8% and 343 g, and (3) 20·0% and 390 g, respectively, though control lambs had the highest weight gains over the 32-day experimental period. Plasma urea nitrogen was lower in both fasted and transported lambs on days 6, 7 and 11 compared with control lambs (P < 0·05). Plasma glucose concentrations on days 4 and 5 were lower in transported lambs than in fasted lambs, and highest in control lambs (P < 0·05); glucose concentration levels remained lower in both fasted and transported lambs than in control lambs on days 6 and 7 (P < 0·05). Plasma cortisol concentrations were highest in transported lambs during the 3-day transport period and for 2 days immediately following transport (P < 0·05). Effects of the 72 h fast were exacerbated by auction barn activity and subsequent transport, and compensatory gains by fasted and transport lambs were incomplete within the 28-day post transport period.
The present investigation explores the use of nitride precipitates for grain-size stabilization in a 18Cr-2ONi austenitic stainless steel for high temperature applications in oxidizing atmospheres. The potential for reductions in alloying contents of such steels has become a focus of research out of concern for the conservation of strategic alloying elements such as Cr. In order for the alloy to maintain superior oxidation resistance, it must sustain a fine grain size by virtue of effective grain boundary pinning by stable precipitates.
Al and Ti microalloyed 18Cr-20Ni steels have been nitrided using rapid solidification processing (spray forming) and subjected to thermomechanical treatments to precipitate nitrides from the supersaturated solid solutions. The spray formed deposits were cold rolled to increase the density of dislocations, which act as sites for nucleation of nitride precipitates. The alloys were then annealed to nucleate and grow the precipitates, followed by cold rolling and recrystallization to generate a stable, fine grained microstructure. The Ti-microalloyed steel demonstrated high-temperature grain size stability by maintaining a grain size of≈7μm after 600h at 1000°C.
The Ti-microalloyed steel has been subjected to isothermal oxidation in air at 900°C. The results of preliminary oxidation experiments are reported. The spray deposited and thermomechanically processed alloy demonstrated high-temperature oxidation behavior superior to conventionally processed (hot rolled and annealed) alloys.
The major alkanone constituents of the resin of Commiphora rostrata, 2-decanone and 2-undecanone, and a series of structural analogues were bioassayed for their repellency against the maize weevil, Sitophilus zeamais in olfactometric assays. All the aliphatic ketones and aldehydes showed comparable or greater activity than the synthetic commercial insect repellent N, N-diethyl toluamide (DEET). In the 2-alkanone series the C-8 and C-9 compounds demonstrated significantly higher activity than their shorter- and longer-chained congeners. Analogues differing in the relative positions of the carbonyl group, including aldehydes, showed a variable pattern of repellency. Alkanols appeared to be mildly attractive to the weevil. The results support our previous suggestion that the resin constituents may play an allomonal role in the ecosystem where the plant thrives.
Fifty-five cases of suicide by doctors under the age of 40 were studied because of concern about deaths among anaesthetists in training. The excess mortality of doctors from suicide was confirmed, suggesting that risk factors associated with being a member of the medical profession continue to operate, although mortality for young male doctors from accidental poisoning is falling. Analysis of the branches of medicine in which the doctors were working showed no definite specialty predominance. There was a somewhat greater risk for women doctors born overseas.
Active metamorphism of fine grained sandstone in the c.16000 year old Salton Sea geothermal system has produced a suite of chemically equilibrated coexisting authigenic alkali feldspars and re-equilibrated detrital feldspars in the 250–360°C temperature range. At c.335°C the average compositions, 2 Vs, and (t1o+t1m) and Z ordering parameters of coexisting authigenic feldspars are [Or0.52Ab97.40An2.08, 2Vx = 91.3±4.8, (t1o + t1m) = 0.89±0.05, Z = 0.79±0.09], and [Or94.42 Ab5.10An0.48, 2Vx = 70, (t1o + t1m) = 0.90, Z = 0.81]. At c.360°C authigenic albite becomes more An-rich and less ordered [Or1.21Ab92.83An5.97, 2Vx = 87.5±3.4, (t1o + t1m) = 0.85±0.03, Z = 0.70±0.07] and K-feldspar is no longer stable. Detrital plagioclase (An up to 40%) is preserved metastably to temperatures up to c.190°C in strongly carbonate-cemented sandstone which forms part of a geothermally produced permeability cap. It undergoes rapid alkali exchange at temperatures near 200°C, and by 250°C no plagioclase with An-content over 12% is observed. At > 250°C authigenic and most detrital alkali feldspar compositions are in excellent agreement with the Bachinski and Muller (1971) microcline-low-albite solvus.
Active geothermal systems in fluvial-deltaic sediment of the Salton Trough typically develop a thick, carbonate-cemented sandstone caprock which shows a regular progression of carbonate minerals, mineral reactions, rock-fluid mass transfer, and physical properties on increasing temperature. The Sinclair 3 well contains calcian ankerite at < 175 °C, ankerite from 175 to 195 °C, calcite+minor dolomite from 195 to about 250°C, and calcite at higher temperatures. The carbonate content of sandstone decreases on increasing temperature from > 45% at < 140 °C to about 10% at > 250 °C, The most abrupt decrease occurs in the 140 to 170°C range where significant compaction of sandstone occurs as carbonate is reduced to < 25%, and kaolinite reacts to form chlorite. The overall result is the loss of significant Ca, Fe, Mg, and CO2 from sandstone to the fluid phase on increasing temperature. Reaction ofcalcian ankerite to ankerite near 175 °C, and of ankerite to calcite and minor dolomite in the 195 to 245°C range, takes place on a constant carbonate-volume basis by direct replacement of one carbonate by another. The latter reaction produces significant chlorite, with Al derived from solution of detrital feldspar and from the smectite-to-illite transformation. The equilibrium coexistence of calcite with dolomite and ankerite near 200 °C has allowed construction of an isothermal section in the Ca-Mg-(Fe+Mn) carbonate phase diagram and provided a low-temperature constraint on the calcite limb of the calcite-dolomite solvus.