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This article evaluates the frictional performance of different bearing grease formulations in full rolling bearings and a ball-on-disc rig and subsequently assesses whether the ball-on-disc test results can be used to predict the grease performance in actual bearings. A selection of custom-made greases with systematically varied formulations as well as their base oils were tested. Bearing torque was measured in two different cylindrical roller thrust bearings and a thrust ball bearing. The same lubricants were tested with ball-on-disc tribometers, a mini traction machine (MTM) to measure friction and an optical elastohydrodynamic (EHD) rig to measure film thickness. Both lithium complex and diurea greases were observed to produce lower friction than their base oils within the low speed, low nominal lambda ratio region, whereas the greases and oils had the same friction at high nominal lambda ratio values. These relative trends were the same in full bearing and single-contact MTM tests. The reduction in friction was seen to be related to the level of film thickness enhancement provided by greases at lower speeds, which leads to an increase in the effective lambda ratio and hence reduced friction. By extracting the sliding torque component from the overall measured bearing torque, a plot of the friction coefficient against the effective lambda ratio was produced encompassing all bearing and single-contact tests and all lubricants and test conditions. This plot was seen to follow a general shape of a master Stribeck curve, indicating that the numerical values of the friction coefficient from ball-on-disc and full bearing tests overlap and can be related to each other using this approach over the range of conditions employed here. Thus, single-contact ball-on-disc tests can provide a fast and economical way of establishing the frictional performance of bearing greases in full bearings in terms of both relative performance rankings and quantitative values of bearing frictional power losses.

© 2020 IOP Publishing Ltd. The detection of gravitational waves from compact binary mergers by LIGO has opened the era of gravitational wave astronomy, revealing a previously hidden side of the cosmos. To maximize the reach of the existing LIGO observatory facilities, we have designed a new instrument able to detect gravitational waves at distances 5 times further away than possible with Advanced LIGO, or at greater than 100 times the event rate. Observations with this new instrument will make possible dramatic steps toward understanding the physics of the nearby Universe, as well as observing the Universe out to cosmological distances by the detection of binary black hole coalescences. This article presents the instrument design and a quantitative analysis of the anticipated noise floor.

The paper presents a comprehensive review of fundamentals and engineering applications of CO2 flow boiling heat transfer, flow patterns and two-phase pressure drops in macro- and micro-channel evaporators. First, distinctions of macro- and micro-channels are discussed. Second, the review addresses the extensive experimental studies on CO2 flow boiling heat transfer and two-phase flow in macro- and micro-channels. The effects of the physical properties on flow boiling heat transfer, flow patterns and pressure drops are analysed by simulations using various physical property packages. Furthermore, analysis of the existing experimental studies of flow boiling heat transfer is presented and the physical mechanisms are discussed. Next, generalized CO2 flow pattern map and flow pattern based mechanistic flow boiling heat transfer and two phase pressure drop models specially developed for CO2 are discussed. New experimental database of flow boiling heat transfer and diabatic two phase frictional pressure drop have been set up to evaluate the models. Comparative results of the flow pattern map, heat transfer and pressure drop models to the experimental database are analysed. In addition, studies of CO2 flow boiling in enhanced channels are summarized. The oil effects on the flow boiling heat transfer and two phase frictional pressure drop are analyzed and simulated as well. According to the extensive analysis, the physical mechanisms and prediction models of the CO2 flow boiling heat transfer and two phase flow phenomena in evaportaors have been well understood. In the aspect of engineering application, comparisons of simulation results and the experimental data in the real thermal systems are discuseed. Furthermore, research need of CO2 evaporators is discussed. Some practical design methods of CO2 evaporators are recommended according to the analysis. Finally, the potential application of CO2 for high heat flux cooling, thermal and power systems are also discussed. Future research needs in flow boiling heat transfer and two phase flow of CO2 in evaporators and engineering applications are discussed and recommended according to this comprehensive review.

To study the role of each two-component system (TCS) histidine kinase (HK) in stress tolerance of Listeria monocytogenes EGD-e, we monitored the growth of individual HIC deletion mutant strains under heat (42.5 degrees C), acid (pH 5.6), alkali (pH 9.4), osmotic (6% NaCl), ethanol (3.5 vol%), and oxidative (5 mM H2O2) stresses. The growth of Delta liaS (Delta lmo1021) strain was impaired under each stress, with the most notable decrease under heat and osmotic stresses. The Delta ivirS (Delta lmo1741) strain showed nearly completely restricted growth at high temperature and impaired growth in ethanol. The growth of Delta agrC (Delta lmo0050) strain was impaired under osmotic stress and slightly under oxidative stress. We successfully complemented the HIC mutations using a novel allelic exchange based approach. This approach avoided the copy-number problems associated with in trans complementation from a plasmid. The mutant phenotypes were restored to the wild-type level in the complemented strains. This study reveals novel knowledge on the HKs needed for growth of L monocytogenes EGD-e under abovementioned stress conditions, with LiaS playing multiple roles in stress tolerance of L monocytogenes EGD-e. (C) 2017 Elsevier Ltd. All rights reserved.

In this paper, we present the colossal dielectric behavior of T-type La2CuO4-delta (LCO) ceramics synthesized in fine grained form using wet chemical "Pechini" process, followed by annealing in argon (Ar) atmosphere. The colossal dielectric constant (CDC) (10(3)

Enchytraeus albidus is a terrestrial earthworm widespread along the coasts of northern Europe and the Arctic. This species tolerates freezing of body fluids and survives winters in a frozen state. Their acclimatory physiological mechanisms behind freeze tolerance involve increased fluidity of membrane lipids during cold exposure and accumulation of cryoprotectants (glucose) during the freezing process. Gene regulatory processes of these physiological responses have not been studied, partly because no gene expression tools were developed. The main aim of this study was to understand whether the freeze tolerance mechanisms have a transcriptomic basis in E. albidus. For that purpose, first the transcriptome of E. albidus was assembled with RNAseq data. Second, two strains from contrasting thermal environments (Germany and Greenland) were compared by mapping barcoded RNAseq data onto the assembled transcriptome. Both of these strains are freeze tolerant, but Greenland is extremely freeze tolerant. Results showed more plastic responses in the Greenland strain as well as higher constitutive expression of particular stress response genes. These altered transcriptional networks are associated with an adapted homeostasis coping with prolonged freezing conditions in Greenland animals. Previously identified physiological alterations in freeze‐tolerant strains of E. albidus are underpinned at the transcriptome level. These processes involve anion transport in the hemolymph, fatty acid metabolism, metabolism, and transport of cryoprotective sugars as well as protection against oxidative stress. Pathway analysis supported most of these processes, and identified additional differentially expressed pathways such as peroxisome and Toll‐like receptor signaling. We propose that the freeze‐tolerant phenotype is the consequence of genetic adaptation to cold stress and may have driven evolutionary divergence of the two strains.

Terrestrial arthropods' ability to survive sub-zero winter temperatures is an important factor influencing their abundance and geographic distribution. It is, therefore, important to understand their physiological mechanisms of low-temperature survival. Acclimation to moderate-low temperature can improve cold tolerance, and pre-acclimation to mild desiccation can also improve survival of a subsequent cold exposure. However, very few studies have assessed the combined actions of cold and drought acclimations. In the present study, we combined cold acclimation with drought acclimation making it possible to assess the interactions between effects of these two stressors using the springtail Protaphorura fimata as a model organism. We investigated the interacting effects of drought and cold acclimation on body fluid osmolality, membrane phospholipid fatty acid (PLFA) composition, and cold-shock tolerance. Acclimation to mild drought (- 2.46 MPa) increased body fluid osmolality from 0.33 to 1.25 Osm at all acclimation temperatures (5, 10, 15, or 20 A degrees C) likely due to accumulation of the compatible osmolytes, trehalose, and alanine. Interestingly, the expected positive effect of drought acclimation on cold-shock tolerance was only evident at high acclimation temperature (20 A degrees C), whereas at intermediate temperatures (10 and 15 A degrees C), there was an interaction between acclimation temperature and drought. At 5 A degrees C, no effect of drought acclimation on cold-shock tolerance was observed despite high osmolality. The positive effect of drought acclimation at 20 A degrees C on subsequent cold-shock survival coincided with a drought-induced effect on PLFA composition only detectable at high temperature. We discuss the possible roles of drought-induced compatible osmolytes and an altered PLFA composition in the cold-shock tolerance of arthropods.

The magnetic, magneto-transport and magnetocaloric properties of antiferromagnetic intermetallic compound NdCo2Si2 (T-N = 32 K) have been studied. The compound yields a positive magnetoresistance (MR) of about similar to 123% at similar to 5 K in 8 T magnetic field. The MR value is significantly large vis - a - vis earlier reports of large MR in intermetallic compounds, and possibly associated with the changes in magnetic structure of the compound. The large MR value can be explained in terms of field induced pseudo-gaps on Fermi surface. (C) 2017 Elsevier B.V. All rights reserved.

We present the first high resolution vacuum ultraviolet photoabsorption study of amorphous benzene with comparisons to annealed crystalline benzene and the gas phase. Vapour deposited benzene layers were grown at 25 K and annealed to 90 K under conditions pertinent to interstellar icy dust grains and icy planetary bodies in our Solar System. Three singlet-singlet electronic transitions in solid benzene correspond to the 1B2u, 1B1u and 1E1u states, redshifted by 0.05, 0.25 and 0.51 eV respectively with respect to the gas phase. The symmetry forbidden 1B2u←1A1g and 1B1u←1A1g transitions exhibit vibronic structure due to vibronic coupling and intensity borrowing from the allowed 1E1u←1A1g transition. Additionally the 1B2u←1A1g structure shows evidence of coupling between intramolecular vibrational and intermolecular lattice modes in crystalline benzene with Davydov crystal field splitting observed. The optically forbidden 0–0 electronic origin is clearly visible as a doublet at 4.69/4.70 eV in the crystalline solid and as a weak broadened feature at 4.67 eV in amorphous benzene. In the case of the 1B1u←1A1g transition the forbidden 0–0 electronic origin is only observed in crystalline benzene as an exciton peak at 5.77 eV. Thicker amorphous benzene samples show diffuse bands around 4.3, 5.0 and 5.4 eV that we tentatively assign to spin forbidden singlet-triplet 3B2u←1A1g, 3E1u←1A1g and 3B1u←1A1g transitions respectively, not previously reported in photoabsorption spectra of amorphous benzene. Furthermore, our results show clear evidence of non-wetting or ‘islanding’ of amorphous benzene, characterised by thickness-dependent Rayleigh scattering tails at wavelengths greater than 220 nm. These results have significant implications for our understanding of the physical and chemical properties and processes in astrochemical ices and highlight the importance of VUV spectroscopy.

Lithium gets a new ground state For the past 70 years, the lowest-energy crystal structure of lithium was believed to be a relatively complex one called the 9R structure. Ackland et al. show that this is incorrect. The actual lowest-energy structure for lithium is the much simpler closest-packed face-centered cubic form. In addition, 6 Li and 7 Li isotopes have crystal phase transitions at slightly different pressures and temperatures. This difference is chalked up to large quantum mechanical effects between the isotopes. Lithium is the only metal that shows this type of quantum effect and presents a challenge for theoreticians to explain. Science , this issue p. 1254

The majority of insects enter a state of reversible coma if temperature is lowered sufficiently. If the cold treatment is not too severe these insects recover gradually when returned to benign temperatures in a time-dependent manner that often depends on the duration and intensity of the cold exposure. Previous studies have associated these phenotypes to changes in membrane potential (V-m) and ion balance, and especially hemolymph [K+] is known to be of importance for the recovery time. In the present study we examined this link in three species of Lepidoptera as insects from this order are known to possess resting hemolymph [K+] that would severely compromise V-m in other insects. Specifically, we exposed larval and adult Manduca sexta, larval Bombyx mori, and adult Heliconius cydno to stressful cold (0 C-omicron) for extended periods of time. Subsequently we measured chill coma recovery time (CCRT), ion- and water balance, and muscle V-m. As expected we find that resting hemolymph [K+] is high and that resting hemolymph [Na+] is low compared to most other insect species. Muscle Vm depolarised considerably during acute cold exposure, but did so in a manner that was not associated with changes in ion balance. However, prolonged cold exposure coincided with an increase of hemolymph [K+] and further depolarisation of V-m which correlated well with prolongation of CCRT. Combined this demonstrates how insects with different ionic compositions generally suffer from similar consequences of cold stress as other species, such that cold tolerance of chill-susceptible insects within Lepidoptera is also intimately linked to maintenance of ion balance and membrane polarisation. (C) 2017 Elsevier Ltd. All rights reserved.

Insect chill tolerance is strongly associated with the ability to maintain ion and water homeostasis during cold exposure. Maintenance of K+ balance is particularly important due to its role in setting the cell membrane potential that is involved in many aspects of cellular function and viability. In most insects, K+ balance is maintained through secretion at the Malpighian tubules, which balances reabsorption from the hindgut and passive leak arising from the gut lumen. Here, we used the scanning ion-selective electrode technique (SIET) at benign (23°C) and low (6°C) temperatures to examine K+ flux across the Malpighian tubules and the rectal pads in the hindgut in five Drosophila species that differ in cold tolerance. We found that chill-tolerant species were better at maintaining K+ secretion and suppressing reabsorption during cold exposure. In contrast, chill-susceptible species exhibited large reductions in secretion with no change, or a paradoxical increase, in K+ reabsorption. Using an assay to measure paracellular leak, we found that chill-susceptible species experience a large increase in leak during cold exposure, which could explain the apparent increase in K+ reabsorption found in these species. Our data therefore strongly support the hypothesis that cold-tolerant Drosophila species are better at maintaining K+ homeostasis through an increased ability to maintain K+ secretion rates and through reduced movement of K+ towards the hemolymph. These adaptations are manifested both at the Malpighian tubule and at the rectal pads in the hindgut, and ensure that cold-tolerant species experience less perturbation of K+ homeostasis during cold stress.

We report quantum transport measurements on two dimensional (2D) Si:P and Ge:P δ-layers and compare the inelastic scattering rates relevant for weak localization (WL) and universal conductance fluctuations (UCF) for devices of various doping densities (0.3–2.5 × 1018 m−2) at low temperatures (0.3–4.2 K). The phase breaking rate extracted experimentally from measurements of WL correction to conductivity and UCF agree well with each other within the entire temperature range. This establishes that WL and UCF, being the outcome of quantum interference phenomena, are governed by the same dephasing rate.

34 págs., 5 tabl. The definitive version is available at: https://www.crops.org/publications/cs, Maize (Zea mays L.) for northern growing areas requires cold tolerance for extending the vegetative period. Our objectives were to evaluate two large panels of maize inbred lines adapted to Europe for cold tolerance and to estimate the effects of cold-related traits on biomass production. Two inbred panels were evaluated for cold tolerance per se and in testcrosses under cold and control conditions in a growth chamber and under field conditions. Comparisons of inbreds and groups of inbreds were made taking into account the single nucleotide polymorphisms (SNP)-based genetic structure of the panels, and the factors affecting biomass production were studied. Eight flint and one dent inbred with diverse origins were the most cold tolerant. The most cold-tolerant dent and flint groups were the Iodent Ph207 and the Northern Flint D171 groups, respectively. The relationships between inbred per se and testcross performance and between controlled and field conditions were low. Regressions with dry matter yield in the field as dependent variable identified plant height (R2 = 0.285) as the main independent variable, followed by quantum efficiency of photosystem II (R2 = 0.034) and other traits with minor contributions. Cold-tolerance–related traits had low and negative effects on dry matter yield. Models intending the prediction of final performance from traits scored in early developmental stages are not expected to be precise enough for breeding. For improving cold tolerance, inbreds released from crosses among the No Iodent group and the Northern Flint group may show high combining ability, as well as between both groups and the Northern Flint D171 group., This research was supported in the framework of the Plant-KBBE program (project acronym “Cornfed”) by the Spanish Ministry of Science and Innovation (proj. EUI2008-03642 and EUI2008-03635), the French National Agency for Research (ANR, Ministry of High Education and Research), and the German Federal Ministry of Education and Research (grant numbers 0315461AD).

Hydrogen Sulfide (H2S) is an odourous, highly toxic gas commonly encountered in various commercial and municipal sectors. Three novel, laboratory-scale, Horizontal-Flow Biofilm Reactors (HFBRs) were tested for the removal of H2S gas from air streams over a 178-day trial at 10 degrees C. Removal rates of up to 15.1 g [H2S] m(-3) h(-1) were achieved, demonstrating the HFBRs as a feasible technology for the treatment of H2S-contaminated airstreams at low temperatures. Bio-oxidation of H2S in the reactors led to the production of H+ and sulfate (SO42-) ions, resulting in the acidification of the liquid phase. Reduced removal efficiency was observed at loading rates of 15.1 g [H2S] m(-3) h(-1). NaHCO3 addition to the liquid nutrient feed (synthetic wastewater (SWW)) resulted in improved H2S removal. Bacterial diversity, which was investigated by sequencing and fingerprinting 16S rRNA genes, was low, likely due to the harsh conditions prevailing in the systems. The HFBRs were dominated by two species from the genus Acidithiobacillus and Thiobacillus. Nonetheless, there were significant differences in microbial community structure between distinct HFBR zones due to the influence of alkalinity, pH and SO4 concentrations. Despite the low temperature, this study indicates HFBRs have an excellent potential to biologically treat H2S-contaminated airstreams. This work was supported by Science Foundation Ireland [grant number 08/RFP/ENM1762] and a European Research Council Starting Grant (3C-BIOTECH; no. 261330). peer-reviewed

The role of hydrogen in promoting the reduction by ammonia of NOx on silver catalysts has been investigated using a Short Time on Stream (STOS) technique to allow differentiation between potentially reactive intermediates and relatively inactive spectator species. Under these conditions, we have used DRIFTS to identify surface nitrate species that are formed and removed on a timescale of seconds. This is in contrast to nitrate species observed under normal steady-state conditions which can continue to form over many tens of minutes. Since this timescale of seconds is very similar to the response rate at which the NH3/NOx to N-2 reaction is accelerated when H-2 is added, or decelerated when H-2 is removed, we conclude that this fast-forming and fast disappearing nitrate species is most probably adsorbed on or close to the active Ag sites. The removal of such a blocking nitrate species from the active sites can explain the effect of H-2 in greatly increasing the rate of the overall de-NOx reaction. (C) 2012 Elsevier Inc. All rights reserved.

Autoignition delay times of stoichiometric methane, ethane and methane/ethane mixtures doped with 100 and 270 ppm of NO2 have been measured in a RCM in the temperature range 900-1050 K and pressures from 25 to 50 bar. The measurements show that addition of NO2 to CH4/O-2/N-2/ Ar and CH4/C2H6/O-2/N-2/Ar mixtures results in a significant reduction in the autoignition delay time and that the ignition-promoting effect of NO2 increases substantially with increasing temperature, from similar to 20% to more than a factor of two over the range of temperature studied. Addition of NO2 to C2H6/O-2/N-2/Ar mixtures results in only a modest reduction in ignition delay time over the range of pressure and temperature measured. Computations with an updated chemical mechanism show good agreement with the measurements for undoped methane, but overpredict the delay times for undoped ethane and underestimate the effects of replacing 10% methane by ethane. For NO2-containing mixtures, the model predicts the observed trend in decreasing delay time with increasing NO2 fraction. However, the computations tend to overestimate the effect of NO2 addition on ignition, particularly for C2H6 mixtures. Analysis of the reaction mechanism for the effects of NO2 addition to methane mixtures indicates that the ignition-promoting effect of NO2 is related to the appearance of new conversion channels for CH3 and CH3OO, i.e., NO2 + CH3 -> NO + CH3O and NO + CH3OO -> NO2 + CH3O, generation of chain-initiating OH radicals through NO/NO2 interconversion, i.e., NO2 + H -> NO + OH and NO + HO2 -> NO2 + OH, and to the direct initiation step CH4+ NO2 -> CH3 + HNO2. Analyses further show that the formation of CH3NO2 via CH3+ NO2(+M) CH3NO2(+M) essentially inactivates NO2. This reaction limits the promoting effect of NO2 at lower temperatures and higher pressures, where stabilization of CH3NO2 is favored, explaining the experimentally observed trends. (C) 2010 The Combustion Institute. Published by Elsevier Inc. All rights reserved.

To prepare bactericide textiles, TiO2 has been added in the form of colloid, powder or a combination of both and the TiO2 modified textiles subsequently cured at temperatures adapted to their specific heat resistance. The bactericide textile is activated and Ag is deposited on the activated cotton or polyester to induce oxygen functionalities containing diverse polar groups. These polar groups increase the bondability of TiO2 and Ag with the textile surface. These functionalities generated in the presence of O-2 by RF-plasma (Radio-frequency plasma) and Vacuum-UV led to an increased adhesion of the TiO2 and Ag on the textiles. Recent findings comprising surface chemistry, photochemistry and microbiology of the bactericide textiles are presented in detail. (C) 2010 Elsevier B.V. All rights reserved.

Current interferometric gravitational wave detectors use the combination of quasi-monochromatic, continuous-wave laser light at 1064 nm and fused silica test masses at room temperature. Detectors of the third generation, such as the Einstein-Telescope, will involve a considerable sensitivity increase. The combination of 1550 nm laser radiation and crystalline silicon test masses at low temperatures might be important ingredients in order to achieve the sensitivity goal. Here we compare some properties of the fused silica and silicon test mass materials relevant for decreasing the thermal noise in future detectors as well as the recent technology achievements in the preparation of laser radiation at 1064 nm and 1550 nm relevant for decreasing the quantum noise. We conclude that silicon test masses and 1550 nm laser light have the potential to form the future building blocks of gravitational wave detection. DFG/EXC/QUEST DFG/SFB/TR7 EC/FP7/2007-2013

The performance of a laboratory-scale sewage treatment system composed of an up-flow anaerobic sludge blanket (UASB) reactor and a moving bed biofilm reactor (MBBR) at a temperature of (22-35 degrees C) was evaluated. The entire treatment system was operated at different hydraulic retention times (HRT's) of 13.3, 10 and 5.0 h. An overall reduction of 80-86% for COD(total); 51-73% for COD(colloidal) and 20-55% for COD(soluble) was found at a total HRT of 5-10 h, respectively. By prolonging the HRT to 13.3 h, the removal efficiencies of COD(total), COD(colloidal) and COD(soluble) increased up to 92, 89 and 80%, respectively. However, the removal efficiency of COD(suspended) in the combined system remained unaffected when increasing the total HRT from 5 to 10 h and from 10 to 13.3 h. This indicates that, the removal of COD(suspended) was independent on the imposed HRT. Ammonia-nitrogen removal in MBBR treating UASB reactor effluent was significantly influenced by organic loading rate (OLR). 62% of ammonia was eliminated at OLR of 4.6 g COD m(-2) day(-1). The removal efficiency was decreased by a value of 34 and 43% at a higher OLR's of 7.4 and 17.8 g COD m(-2) day(-1), respectively. The mean overall residual counts of faecal coliform in the final effluent were 8.9 x 10(4) MPN per 100 ml at a HRT of 13.3 h, 4.9 x 10(5) MPN per 100 ml at a HRT of 10 h and 9.4 x 10(5) MPN per 100 ml at a HRT of 5.0 h, corresponding to overall log(10) reduction of 2.3, 1.4 and 0.7, respectively. The discharged sludge from UASB-MBBR exerts an excellent settling property. Moreover, the mean value of the net sludge yield was only 6% in UASB reactor and 7% in the MBBR of the total influent COD at a total HRT of 13.3 h. Accordingly, the use of the combined UASB-MBBR system for sewage treatment is recommended at a total HRT of 13.3 h.

Ascites syndrome is a metabolic disorder in broilers. Mortality due to ascites results in significant economic losses and has a negative impact on animal welfare. It has been shown that genetic factors play a considerable role in susceptibility of birds to ascites, which offers perspectives for selection against this syndrome. The aim of the present study was to evaluate the consequences of alternative selection strategies for BW and resistance to ascites syndrome using deterministic simulation. In addition to the consequences of current selection (i.e., selection for increased BW only) alternative selection strategies including information on different ascites-related traits measured under normal or cold conditions and the consequences of having information on the underlying genes (i.e., MAS) were quantified. Five different breeding schemes were compared based on the selection response for BW, ascites susceptibility, and the rate of inbreeding. Traits investigated in the index as indicators for ascites were hematocrit value (HCT) and ratio of right ventricle to the total ventricular weight of the heart (RV:TV). The results indicated that by ignoring ascites susceptibility in the breeding goal, the gain for BW is 130 g and the birds will become more susceptible to ascites. Testing 50% of the birds under cold temperature conditions and including information of ascites related traits (HCT and RV:TV) measured under normal and cold conditions makes it possible to achieve a relatively high gain for BW (111.4 g) while controlling the genetic level for ascites susceptibility (selection response was 0). The results of scenarios including QTL information of ascites susceptibility showed that QTL information could be used very effectively in controlling ascites susceptibility.

The use of legumes as green manuring crops does involve a potential riskof N leaching losses over the winter period. The susceptibility of cropresidue-derived N to losses and the pre-crop value of a green manuring crop canbe manipulated by proper timing of incorporation into soil. In this study,mineralization of C and N was investigated in a range of low temperatures,including thawing and freezing, that are characteristic to autumn green manureincorporation and its decomposition. The pre-crop effect of green manuring wasfurther tested with spring wheat under field conditions. We hypothesized thatdelaying green manure incorporation in the autumn would reduce the risk of Nlosses from the field and maximize the N transfer to a successive spring wheatcrop. To test the hypothesis, N mineralization was followed in alaboratory experiment where red clover (Trifoliumpratense L.) shoots were incubated at 4¿8 °Cfor 40¿80 days to simulate early autumn, delayed autumn and late autumnincorporation of a green manuring crop, followed by an incubation at¿2 °C or at ¿2 °C to+4 °C for 25 days to simulate winter conditions. In asimultaneous field experiment, we measured the effect ofdelayed autumn incorporation of common vetch (Vicia sativaL.) green fallow on spring wheat performance. In the laboratoryexperiment, significant N mineralization during incubation wasdetected when simulating both early autumn and delayed autumn incorporation. Incontrast, no net N mineralization was detected when simulating lateincorporation. In the field experiment, the N supply fromsoil to spring wheat was higher in the late and delayed incorporationtreatmentsthan in early or spring incorporation of green manure. Late incorporationalso produced most wheat grain. We conclude that different amounts of N becomeavailable to wheat, depending on the time of incorporation of green manureresidues in soil. This difference is due to temperature. Late or delayedincorporation of green manure residues has the potential to reduce thesusceptibility of mineral N to leaching and yields more N available to asubsequent crop.

Profound understanding of the mechanisms foodborne pathogenic bacteria utilize in adaptation to the environmental stress they encounter during food processing and storage is of paramount importance in design of control measures. Chill temperature is a central control measure applied in minimally processed foods; however, data on the mechanisms the foodborne pathogen Clostridium botulinum activates upon cold stress are scarce. Transcriptomic analysis on the C. botulinum ATCC 3502 strain upon temperature downshift from 37°C to 15°C was performed to identify the cold-responsive gene set of this organism. Significant up- or down-regulation of 16 and 11 genes, respectively, was observed 1 h after the cold shock. At 5 h after the temperature downshift, 199 and 210 genes were up- or down-regulated, respectively. Thus, the relatively small gene set affected initially indicated a targeted acute response to cold shock, whereas extensive metabolic remodeling appeared to take place after prolonged exposure to cold. Genes related to fatty acid biosynthesis, oxidative stress response, and iron uptake and storage were induced, in addition to mechanisms previously characterized as cold-tolerance related in bacteria. Furthermore, several uncharacterized DNA-binding transcriptional regulator-encoding genes were induced, suggesting involvement of novel regulatory mechanisms in the cold shock response of C. botulinum. The role of such regulators, CBO0477 and CBO0558A, in cold tolerance of C. botulinum ATCC 3502 was demonstrated by deteriorated growth of related mutants at 17°C.

The surface modification of a mechanochemically prepared Ag/Al O catalyst compared with catalysts prepared by standard wet impregnated methods has been probed using two-dimensional T -T NMR correlations, HO temperature programmed desorption (TPD) and DRIFTS. The catalysts were examined for the selective catalytic reduction of NO using n-octane in the presence and absence of H. Higher activities were observed for the ball milled catalysts irrespective of whether H was added. This higher activity is thought to be related to the increased affinity of the catalyst surface towards the hydrocarbon relative to water, following mechanochemical preparation, resulting in higher concentrations of the hydrocarbon and lower concentrations of water at the surface. DRIFTS experiments demonstrated that surface isocyanate was formed significantly quicker and had a higher surface concentration in the case of the ball milled catalyst which has been correlated with the stronger interaction of the n-octane with the surface. This increased interaction may also be the cause of the reduced activation barrier measured for this catalyst compared with the wet impregnated system. The decreased interaction of water with the surface on ball milling is thought to reduce the effect of site blocking whilst still providing a sufficiently high surface concentration of water to enable effective hydrolysis of the isocyanate to form ammonia and, thereafter, N. This journal is © The Royal Society of Chemistry.

The structural changes throughout the entire reductive radiation-induced pathway of L-alpha-alanine are solved on an atomistic level with the aid of periodic DFT and nudged elastic band (NEB) simulations. This yields unprecedented information on the conformational changes taking place, including the protonation state of the carboxyl group in the "unstable'' and "stable'' alanine radicals and the internal transformation converting these two radical variants at temperatures above 220 K. The structures of all stable radicals were verified by calculating EPR properties and comparing those with experimental data. The variation of the energy throughout the full radiochemical process provides crucial insight into the reason why these structural changes and rearrangements occur. Starting from electron capture, the excess electron quickly localizes on the carbon of a carboxyl group, which pyramidalizes and receives a proton from the amino group of a neighboring alanine molecule, forming a first stable radical species (up to 150 K). In the temperature interval 150-220 K, this radical deaminates and deprotonates at the carboxyl group, the detached amino group undergoes inversion and its methyl group sustains an internal rotation. This yields the so-called "unstable alanine radical''. Above 220 K, triggered by the attachment of an additional proton on the detached amino group, the radical then undergoes an internal rotation in the reverse direction, giving rise to the "stable alanine radical'', which is the final stage in the reductive radiation-induced decay of alanine.

The efficiency of the future devices for quantum information processing will be limited mostly by the finite decoherence rates of the individual qubits and quantum gates. Recently, substantial progress was achieved in enhancing the time within which a solid-state qubit demonstrates coherent dynamics. This progress is based mostly on a successful isolation of the qubits from external decoherence sources obtained by clever engineering. Under these conditions, the material-inherent sources of noise start to play a crucial role. In most cases, quantum devices are affected by noise decreasing with frequency, f, approximately as 1/f. According to the present point of view, such noise is due to material- and device-specific microscopic degrees of freedom interacting with quantum variables of the nanodevice. The simplest picture is that the environment that destroys the phase coherence of the device can be thought of as a system of two-state fluctuators, which experience random hops between their states. If the hopping times are distributed in a exponentially broad domain, the resulting fluctuations have a spectrum close to 1/f in a large frequency range. In this paper we review the current state of the theory of decoherence due to degrees of freedom producing 1/f noise. We discuss basic mechanisms of such noises in various nanodevices and then review several models describing the interaction of the noise sources with quantum devices. The main focus of the review is to analyze how the 1/f noise destroys their coherent operation. We start from individual qubits concentrating mostly on the devices based on superconductor circuits, and then discuss some special issues related to more complicated architectures. Finally, we consider several strategies for minimizing the noise-induced decoherence., Comment: Revised manuscript accepted for publication in Rev. Mod. Phys. 63 pages, 44 figures

The response of five Lycopersicon species to 14 days moderate chilling at 10 degrees C under low light (75 mu mol m(-2) s(-1)) and subsequent recovery was examined by measurements on relative shoot growth rate, leaf dry matter and carbohydrate content, CO2-exchange and pigment composition. In addition, the susceptibility to dark chilling and temperature dependence of chloroplast electron transport were analyzed by Chl a fluorescence measurements. During 7 days of recovery at 25/20 degrees C subsequent to chilling, the domestic tomato Lycopersicon esculentum (L.) Mill. cv. Abunda exhibited a small capacity for shoot regrowth (39%) compared to the low-altitude wild species L. pimpinellifolium (Jusl.) Mill. PI187002 (82%) and three wild species originating from high altitude: L, peruvianum Mill. LA 385 (92%), L, hirsutum Humb, & Bonpl. LA 1777 (67%) and L. chilense Dunn. LA 1970 (71%). The inter-specific differences in chilling sensitivity at the chloroplast level, analyzed by the decline of the maximum rate of induced Chl fluorescence rise (F-R) after 40 h at 0 degrees C and the temperature at which q(P) reached the value 0.5, correlated in general well with the measured differences at whole plant level, measured by the post-chilling regrowth capacity. Chilling resulted in a larger increase in leaf dry matter content in L. esculentum (45%) and L. pimpinellifolium (37%) compared to the high-altitude species (13-16%), which could be attributed to a stronger accumulation of both soluble sugars and starch in mature leaves of the domestic and low-altitude species. Photosynthetic and dark respiration rates during chilling could not account for this difference, The recovery of photosynthesis was better in the high-altitude species, Chl content per unit leaf area decreased more throughout the experiment in the domestic and low-altitude species (63-73%) than in their relatives from high altitude (8-29%), In response to chilling, the domestic and low-altitude species showed an increase in the total xanthophyll cycle pool on Chl basis, whereas the de-epoxidation state of the xanthophyll cycle increased in the high-altitude wild species. Both responses resulted in increased zeaxanthin levels in chilled leaves of all Lycopersicon species.

A family of genes encoding cold-shock proteins, named cspA, cspB, cspC, cspD and cspE, was cloned and sequenced from Lactococcus lactis MG1363. The genes cspA and cspB and the genes cspC and cspD are located in tandem repeats, an organization of csp genes that has never been encountered before. The five genes encode small (7.1-7.6 kDa) proteins with high mutual sequence identities (up to 85%) and high identities (about 45-65%) with the major cold-shock proteins from Escherichia coli (CspA) and Bacillus subtilis (CspB), Northern-blot analysis revealed single transcripts of about 300 nucleotides for each csp gene and showed that cspA, cspB, cspC and cspD mRNA levels were strongly increased upon cold shock to 10 degrees C (about 10-, 40-, 10- and 30-fold compared to 30 degrees C, respectively), whereas the cspE mRNA level was not increased. The expression of the cold-induced csp genes was highest in the 6-8 h lag phase after cold shock. A differential expression in time, in which cspA and cspC were maximally expressed at 2 h and cspB and cspD at 4 h after cold shock, was observed. The -35 and -10 regions of the five promoters were identified and transcriptional start sites were mapped in each case by primer extension at different temperatures which confirmed that regulation takes place at the transcriptional level. Significant differences were observed between the 5'-untranslated leader regions of the four cold-induced csp genes and the corresponding region of the non-cold-induced cspE gene.

Morphological changes in the knee joint elements of laboratory rats after exposure to low temperatures and ethanol were studied. It was found out that an injection of ethanol, precooled down to .114 o„R, .50 o„R, .35 o„R, into the joint cavity resulted in damages of the articular cartilage, articular capsule, menisci and subchondral bone depending upon the temperature range. Significant destructive changes were registered in cases of ethanol cooling down to temperatures of .114 and .50 o„R., Изучены морфологические изменения элементов коленного сустава лабораторных крыс после воздействия низких температур и этанола. Установлено, что введение предварительно охлажденного до –114, –50, –35 ºС этанола в полость сустава приводит к повреждению суставного хряща, капсулы сустава, менисков и субхондральной кости в зависимости от температурного диапазона. Выраженные деструктивные изменения зафиксированы в случае охлаждения этанола до температуры –114 и –50 ºС., Вивчені морфологічні зміни елементів колінного суглоба лабораторних щурів після впливу низьких температур та етанолу. Встановлено, що введення попередньо охолодженого до –114, –50, –35 ºС етанолу в порожнину суглоба призводить до ушкодження суглобового хряща, капсули суглоба, менісків та субхондральной кістки залежно від температурного діапазону. Виражені деструктивні зміни зафіксовані в разі охолодження етанолу до температури –114 та –50 ºС.

A reduction in phonon thermal conductivity enhances thermoelectric performance. One method to accomplish this is by applying mechanical stress to a nanostructure. We consider an initially twisted 20 nm polyvinyl acetate nanofiber undergoing torsion. Our analytical method uses the continuum approach of Mooney's model. Torsion modifies the phonon dispersion. Angles of twist between 45 degrees and 70 degrees reduce the averaged phonon group velocity and the phonon thermal conductivity but when these angles are increased further, this conductivity increases. This suggests a phonon engineering approach to tune the thermal conductivity of nanomaterials. (C) 2013 AIP Publishing LLC. National Nanotechnology Center (NANOTEC)

CoSb3is an example of a highly challenging case for experimental charge-density analysis due to the heavy elements (suitability factor of ∼0.01), the perfect crystallinity and the high symmetry of the compound. It is part of a family of host–guest structures that are potential candidates for use as high-performance thermoelectric materials. Obtaining and analysing accurate charge densities of the undoped host structure potentially can improve the understanding of the thermoelectric properties of this family of materials. In a previous study, analysis of the electron density gave a picture of covalent Co–Sb and Sb–Sb interactions together with relatively low atomic charges based on state-of-the-art experimental and theoretical data. In the current study, several experimental X-ray diffraction data sets collected on the empty CoSb3framework are compared in order to probe the experimental requirements for obtaining data of high enough quality for charge-density analysis even in the case of very unsuitable crystals. Furthermore, the quality of the experimental structure factors is tested by comparison with theoretical structure factors obtained from periodic DFT calculations. The results clearly show that, in the current study, the data collected on high-intensity, high-energy synchrotron sources and very small crystals are superior to data collected at conventional sources, and in fact necessary for a meaningful charge-density study, primarily due to greatly diminished effects of extinction and absorption which are difficult to correct for with sufficient accuracy.

We study the Pb growth on both root 3 x root 3-In and 4 x 1-In reconstructed Si(111) surfaces at room and low temperature (160 K). The study takes place with complementary techniques, to investigate the role of the substrate reconstruction and temperature in determining the growth mode of Pb. Specifically, we focus on the correlation between the growth morphology and the electronic structure of the Pb films. The information is obtained by using Auger electron spectroscopy, low energy electron diffraction, soft x-ray photoelectron spectroscopy, scanning tunneling microscopy and spot profile analysis-low energy electron diffraction. The results show that, at low temperature and coverage

We have measured the temperature dependence of the conductance of long V-groove quantum wires fabricated using GaAs/AlGaAs heterostructures, in a wide temperature range (200 mK < T < 4.2 K). We find that for our quantum wires the Fermi velocity can be as low as nu(F) congruent to 5 x 10(4) m/s, corresponding to an interaction parameter value of g congruent to 0.56. This value suggests that our data are consistent with theories developed within the framework of the Luttinger liquid model in the presence of a single strong barrier (weak link).

In this work, the atomistic Green's function method is extended to compute transmission functions for each phonon polarization. The eigenvectors and eigenvalues of the overall density of states matrices are manipulated to yield a density of states matrix for each polarization. A decomposed self-energy is calculated from the density of states matrix for each polarization and used to calculate the transmission function for a particular phonon branch. In a pure bulk material such as silicon, each transmission function exhibits a frequency-independent value of unity. In heterogeneous bulk materials, the transmission function is reduced significantly due to the junction of dissimilar materials. [DOI: 10.1115/1.4004400]

The ribosome-bound trigger factor (TF) chaperone assists folding of newly synthesized polypeptides and participates in the assembly of macromolecular complexes. In the present study we showed that multiple distinct TF paralogues are present in genomes of Desulfitobacteria, a bacterial genus known for its ability to grow using organohalide respiration. Two full-length TF chaperones and at least one truncated TF (lacking the N-terminal ribosome-binding domain) were identified, the latter being systematically linked to clusters of reductive dehalogenase genes encoding the key enzymes in organohalide respiration. Using a well-characterized heterologous chaperone-deficient Escherichia coli strain lacking both TF and DnaK chaperones, we demonstrated that all three TF chaperones were functional in vivo, as judged by their ability to partially suppress bacterial growth defects and protein aggregation in the absence of both major E. coli chaperones. Next, we found that the N-terminal truncated TF-like protein PceT functions as a dedicated chaperone for the cognate reductive dehalogenase PceA by solubilizing and stabilizing it in the heterologous system. Finally, we showed that PceT specifically interacts with the twin-arginine signal peptide of PceA. Taken together, our data define PceT (and more generally the new RdhT family) as a class of TF-like chaperones involved in the maturation of proteins secreted by the twin-arginine translocation pathway.

Mixed oxides of the general formula La(0.8)Sr(0.2)FeO(3-x) were prepared by ceramic and surfactant methods and tested towards the NO/H(2)/O(2) and NO/CH(4)/O(2) lean-deNO(x) reactions in the 200-450 degrees C range. The materials were characterized for their bulk and surface composition by XRD, Mossbauer and XPS techniques. The main crystal phases detected were perovskites LaFeO(3) and SrFeO(3-x), and alpha-Fe(2)O(3). The Mossbauer technique allowed the precise determination of the composition of Fe-containing phases in the solids prepared by both the ceramic and surfactant methods. Significant differences in the composition of the phases and the surface chemical states of Fe, Sr and La were revealed among the two solid compositions. For the CH(4) lean-deNO(x) reaction at 350 degrees C, the La(0.8)Sr(0.2)FeO(3-x) solid composition (LSF-2) prepared by the surfactant method exhibited an increase by 50% in the rate of NO conversion and by 30% in the rate of N(2) formation (per gram basis) as compared to the solid prepared by the ceramic method (LSF-1). An opposite relative catalytic activity behavior was observed for the two solids when tested towards the H(2) lean-deNO(x) reaction. At 375 degrees C (maximum activity observed) the solid prepared by the ceramic method (LSF-1) exhibited an increase by 83% in the rate of N(2) formation as compared to the solid prepared by the surfactant method (LSF-2). It is suggested that the mobility of surface lattice oxygen, the concentration of oxygen vacant sites, and the mixed valences of metal cations present in the La(0.8)Sr(0.2)FeO(3-x) solid all influenced by the preparation method used are the main parameters that largely influenced the catalytic behavior observed over the LSF-1 and LSF-2 solids. (C) 2009 Elsevier B.V. All rights reserved. Applied Catalysis B-Environmental

Microelectronics has shaped the world beyond what was thought possible at the time of its advent. One area of current research in this field is on the solid-state Si:P-based quantum computer (QC). In this machine, each qubit requires an individually addressed fast control-pulse for non-adiabatic drive and measure operations. Additionally, it is increasingly becoming important to be able to interface nanoelectronics with complementary metal-oxide-semiconductor (CMOS) technology. In this work, I have designed and demonstrated full-custom mixed-mode and full-digital fast control-pulse generators fabricated in a silicon-on-sapphire (SOS) CMOS commercial foundry process a radio-frequency (RF) CMOS technology. These circuits are, fundamentally, fast monostable multivibrators. Initially, after the design specifications were decided upon, I characterized NFET and PFET devices and a n+-diffusion resistor from 500 nm and 250 nm commercial SOS-CMOS processes. Measuring their conductance curves at 300 300 K, 4.2 2 K, and sub-K (30 30 mK base to 1000 1000 mK) showed that they function with desirable behaviour although exhibiting some deviations from their 300 300 K characteristics. The mixed-mode first generation control-pulse generator was demonstrated showing that it produced dwell-time adjustable pulses with 100 100 ps rise-times at 300 K, 4.2 2 K, and sub-K with a power dissipation of 12 12 uW at 100 100 MHz. The full-digital second generation control-pulse generator was demonstrated showing accurately adjustable dwell-times settable via a control-word streamed synchronously to a shift-register. The design was based on a ripple-counter with provisions for internal or external clocking. This research has demonstrated that SOS-CMOS technology is highly feasible for the fabrication of control microelectronics for a Si:P-based QC. I have demonstrated full-custom SOS-CMOS mixed-mode and full-digital control circuits at 300 300 K, 4.2 2 K, and sub-K which suitable for qubit control.