Background Rapid detection of respiratory viruses is important for management and infection control in hospitalized patients. Multiplex nucleic acid tests (NATs) have begun to replace conventional methods as gold standards for respiratory virus detection. Objective To compare the performance of two large multiplex NATS, ResPlex II (RPII) and Respiratory Virus Surveillance kit with electrospray ionization mass spectrometry (RVS/MS) using nasopharyngeal aspirates (NPAs) from hospitalized children who had been tested previously with conventional methods. Study design Stored residual NPAs (N = 306) were tested concomitantly by RPII and RVS/MS. Alternate NATs were used to adjudicate discordant results. Results More viruses were detected with multiplex NATs (RPII, 110; RVS/MS, 109) than conventional assays (86); diagnostic gain was primarily for fastidious viruses (coronaviruses and enteroviruses [EVs]/human rhinoviruses [HRVs]). Total positive and negative agreement between the multiplex NATs for all viruses detected was quite high (86% positive agreement, 99% negative agreement). Most individual viruses were detected with fairly equivalent accuracy by the multiplex NATs, except for adenoviruses (RPII sensitivity 40%) and human metapneumovirus (RVS/MS sensitivity 42%). RPII had the advantage of detecting EVs and HRVs, however, it demonstrated considerable EV/HRV cross-reactivity (29 HRV-positive specimens by real-time PCR were positive for EV by RPII and 21 specimens positive for HRV only by RT-PCR were dual positive for EV/HRV by RPII). RPII also had reduced sensitivity for HRV detection (in 36 specimens, HRV was detected by RT-PCR but not by RPII). Conclusions Both multiplex NATs were promising, but had notable limitations.

The microstructure of Low Pressure Chemical Vapor Deposition (LPCVD) Polycrystalline silicon (Polysilicon) thin films was investigated by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), atomic force microscopy (AFM) and Auger electron spectroscopy (AES). SEM characterization of tensile tested samples showed a brittle like-rupture, along with grooves located at the surface sides of the sample. TEM investigations of as-deposited samples showed equiaxed or fully columnar grains bridging from the bottom to the top of the films. A microstructural coarsening was observed with annealing. In the as-deposited state, the films exhibited a {110} texture as showed by the XRD analysis. The films' top and bottom surfaces were observed to be smooth with a roughness (standard deviation) of about 11nm and 20 nm respectively. A chemical analysis of the thin films showed the presence of carbon and oxygen impurities on the surface and oxygen through the sample as observed in the depth profile. The hypothetical influence of these findings is subsequently discussed in relation to the measured mechanical properties.

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Variation in production of cool-season forages over a typical grazing period increases the risk of failing to meet livestock nutrient needs. Th e objective of this study was to evaluate the risk-buff ering capacity of warm-season forages to fi ll the summer slump in production of cool-season grasses in the Appalachian region. Small-plot experiments were initiated in the summer of 2008 at three sites in Virginia. Treatments included three tall fescue [Schedonorus phoenix (Scop.) Hulub] types (endophyte-infected [KY31 E+], endophyte free [KY31 E-], and novel endophyte [Max Q]), Teff [Eragrotis tef (Zucc.) Trotter], bermudagrass [Cynodon dactylon (L.) Pers.] (BG), and Caucasian bluestem [Bothriochloa bladhii (Retz) S.T. Blake] (CB). Plots were harvested May through October of 2009 and 2010 at the late boot stage at a cutting height of 10 cm. Subsamples were analyzed for dry matter and nutritive value.To assess risk, bootstrap distributions of biomass and quality data were generated by Monte Carlo simulation and compared against an objective function defi ned as 59 kg ha -1 d -1 forage yield; 100 g kg -1 crude protein (CP); 600 g kg -1 total digestible nutrients (TDN). Th e warm-season grasses produced biomass yields and nutritional values adequate to fi ll the summer slump from cool-season forages and demonstrated a higher probability of meeting the minimum requirements in July, August, and September. Teff was most consistent in meeting the minimum requirements in mid-summer. However, both BG and CB can help to fi ll the gap in summer months when compared to cool-season tall fescue. Bootstrap distributions provide producers with a tool that links their production goals with a measurable value of production risk.