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Closed field unbalanced magnetron sputtering was used to deposit diamond-like carbon (Ti-C:H) coatings on Ti6Al4V alloy and gas nitrided Ti6Al4V alloy. Four different specimens were prepared, namely untreated Ti6Al4V alloy (Ti6Al4V), gas nitrided Ti6Al4V alloy (N-Ti6Al4V), Ti-C:H-coated Ti6Al4V alloy (Ti-C:H/Ti6Al4V) and Ti-C:H-coated gas nitrided Ti6Al4V alloy (Ti-C:H/N-Ti6Al4V). The tribological properties of the four specimens were evaluated using a reciprocating wear tester sliding against a Si3N4 ball (point contact mode) and 316L stainless steel cylinder (line contact mode). The wear tests were performed in a 0.89 wt.% NaCl solution. The results showed that the nitriding treatment increased the surface roughness and hardness of the Ti6Al4V alloy and improved the wear resistance as a result. In addition, the Ti-C:H coating also improved the tribological performance of Ti6Al4V. For example, compared to the untreated Ti6Al4V sample, the Ti-C:H coating reduced the wear depth and friction coefficient by 340 times and 10 times, respectively, in the point contact wear mode, and 151 times and 9 times, respectively, in the line contact wear mode. It is thus inferred that diamond-like carbon coatings are of significant benefit in extending the service life of artificial biomedical implants.

The transcriptional repressor Slug is best known to control epithelial-mesenchymal transition (EMT) and promote cancer invasion/metastasis. In this study, we demonstrate that Slug is temporally regulated during cell cycle progression. At G1/S transition, cyclin E-cyclin-dependent kinase 2 mediates the phosphorylation of Slug at Ser-54 and Ser-104, resulting in its ubiquitylation and degradation. Non-phosphorylatable Slug is markedly stabilized at G1/S transition compared with wild-type Slug and greatly leads to downregulation of DNA synthesis and checkpoint-related proteins, including TOP1, DNA Ligase IV and Rad17, reduces cell proliferation, delays S-phase progression and contributes to genome instability. Our results indicate that Slug has multifaceted roles in cancer progression by controlling both EMT and genome stability.

Traumatic brain injury (TBI) is a common diagnosis in the emergency department. Brain computed tomography (CT) has become a standard diagnostic tool with which to examine TBI patients. Conventional X-rays are ineffective for the evaluation of torso or extremity injuries. In the current study, we attempted to establish a diagnostic modality to evaluate systemically initially unconscious patients in the emergency department with a rapid screening technique characterized by sufficient information, low cost and low radiation exposure. From January 2008 to December 2009, patients with diminished level of consciousness received the Lodox/Statscan for evaluation of extracranial injuries were enrolled in this study. The accuracy of this diagnostic modality in detecting torso or extremity injuries in initially unconscious patients was analyzed by comparing the initial diagnosis (by the Lodox/Statscan) with the final diagnosis (confirmed by torso CT scan or after two weeks of follow-up). There were 1,210 patients with TBI whose extracranial injuries were evaluated by the Lodox/Statscan. After excluding intra-abdominal injuries, the overall sensitivity rates of the Lodox/Statscan in diagnosing torso injuries and extremity injuries were 89.7% and 90.2%, respectively. No long bone fracture was missed by the Lodox/Statscan. The sensitivity and specificity of the Lodox/Statscan in diagnosing long bone fractures were both 100%. Most patients with torso injuries that were missed by the Lodox/Statscan could be managed conservatively without further treatment or complications. All of the missed extremity injuries were distal bone fractures. The Lodox/Statscan can provide benefits for surveying extracranial injuries in patients with diminished level of consciousness. The Lodox/Statscan also emits a notably low dose of radiation and appears to be a relatively inexpensive adjunct to screen torso or extremity injuries in TBI patients.

We have observed emission from both ortho and para spin states of ketene (CH2CO) towards several deeply-embedded protostars. The low CH2CO fractional abundances (∼10−10) and the rotation temperatures (∼20 K) are consistent with emission from the cooler envelope. We compare our results with previous studies and discuss possible production pathways to interstellar ketene. We suggest that, if low observed excitation temperatures of CH2CO, CH3CHO and H2CO are indicative of their absence from the hot core region, then this may be due to the extensive hydrogenation of pre-existing grain mantles prior to evaporation into the inner envelope, leading to lower abundances of these compounds and to mantles rich in alcohols.

Blossom blight, caused bySclerotinia sclerotiorum, has become an important disease of alfalfa (Medicago sativa L.) in seed production areas of western Canada. Studies using light microscopy and scanning and transmission electron microscopy revealed that pollen grains of alfalfa are susceptible to infection byS. sclerotiorum. Ascospores ofS. sclerotiorum germinated readily in water with or without pollen grains. Examinations of ascospore—pollen mixtures incubated at room temperature (20–22°C) for 5 days revealed that numerous pollen grains were infected byS. sclerotiorum by direct hyphal penetration through the equatorial germinative pores or through the exine and intine layers of the pollen wall without the formation of infection cushions or appressoria. After penetration, hyphae ramified within the pollen grains, causing plasmolysis of the cytoplasmic membrane and eventual disintegration of the pollen cytoplasm. The study suggests that alfalfa pollen may play a role in the epidemiology of blossom blight in alfalfa.

This paper considers the problem of on-line scheduling a list of independent jobs in which each job has an arbitrary release time on m parallel identical machines. A tight bound is given for List Scheduling(LS) algorithm and a better algorithm is given for m≥2.

In seeds, the subcellular storage oil bodies have a matrix of oils (triacylglycerols) surrounded by a layer of phospholipids embedded with abundant structural proteins called oleosins. We used two maize (Zea mays L.) strains having diverse kernel (seed) oil contents to study the effects of varying the oil and oleosin contents on the structure of the oil bodies. Illinois High Oils (IHO, 15% w/w oils) and Illinois Low Oils (ILO, 0.5%) maize kernels were the products of breeding for diverse oil contents for about 100 generations. In both maize strains, although the genes for oil synthesis had apparently been modified drastically, the genes encoding oleosins appeared to be unaltered, as revealed by Southern blot analyses of the three oleosin genes and sodium dodecyl sulfate-polyacrylamide gel electrophoresis with immunoblotting of the oleosins. In addition, both strains contained the same three oleosin isoforms of a defined proportion, and both accumulated oils and oleosins coordinately. Oleosins in both strains were restricted to the oil bodies, as shown by analyses of the various subcellular fractions separated by sucrose-density-gradient centrifugation. Electron microscopy of the embryos and the isolated organelles revealed that the oil bodies in IHO were larger and had a spherical shape, whereas those in ILO were smaller and had irregular shapes. We conclude that in seeds, oleosin genes are expressed independent of the oil contents, and the size and shape of the oil bodies are dictated by the ratio of oils to oleosins synthesized during seed maturation. The extensive breeding for diverse oil contents has not altered the apparent mechanism of oil-body synthesis and the occurrence of hetero-dimer or -multimer of oleosin isoforms on the oil bodies.

Oleosins, which are structural proteins on the surface of intracellular oil bodies, have been found in the sporophytic seeds of angiosperms. Here, we report an oleosin from the female gametophyte of gymnosperm Pinus ponderosa Laws. seed and another oleosin from the male gametophyte of Brassica napus L. With the pine seed gametophyte, we identified two putative oleosins of 15 and 10 kDa, which are similar to the oleosins in angiosperm seeds in terms of their presence in the oil bodies in massive quantity. The complete sequence of the cDNA encoding the gametophytic 15-kDa oleosin was obtained, and it has a predicted amino-acid sequence similar to those of oleosins in angiosperm sporophytic seeds. A Brassica napus pollen cDNA sequence, which was reported earlier, would encode an amino-acid sequence somewhat similar to those of seed oleosins. We tested if the dissimilarity signifies a substantially different oleosin in the Brassica male gametophyte or an analytic error. By direct sequencing of a polymerase chain reaction (PCR)-amplified fragment of genomic DNA, we obtained evidence showing that this reported dissimilarity is likely to have arisen from a sequencing error. Our predicted sequence of the Brassica pollen oleosin has all the structural characteristics of seed oleosins. A phylogenic tree of 20 oleosins, including those from sporophytic and gametophytic tissues of angiosperm and gymnosperm, was constructed based on their amino-acid sequences. We discuss the evolution of oleosins, and conclude that oleosins are ancient proteins with multiple lineages whose root cannot be determined at this time.

The possible interaction of high soil salinity and low soil nitrogen content in affecting the growth of Spartina alterniflora Loisel in the high and low marshes of the Eastern U.S. was explored. Throughout the whole growing season, the short plants growing in the high marsh, where there was a higher soil salinity and lower available soil nitrogen, contained more proline and glycinebetaine and showed a lower leaf water potential than the tall plants growing in the low marsh. In both short and tall plants, the growing season, with the highest content occurring in spring and fall. In contrast, the glycinebetaine content in both short and tall plants remained fairly constant throughout the growing season, and was consistently at least 10 fold higher than the proline content. It is estimated that 19-30% of the total leaf nitrogen was in the form of proline and glycinebetaine in the short plants, and 14-27% in the tall plants. Ammonium nitrate fertilization in the field resulted in increased growth, higher proline and glycinebetaine contents, and lower water potentials in the short plants, but had little effect on these parameters in the tall plants. We suggest that in the low marsh, the plants can obtain sufficient nitrogen for osmoregulation and other metabolism. In the high marsh with higher soil salinity and lower nitrogen content, the plants have to allocate a even greater proportion of the already limited nitrogen supply for osmoregulation. Thus, nitrogen available for osmoregulation and other nitrogen-requiring metabolism is insufficient, resulting in reduced growth.