The photolysis of N2O at 1470 A. Ionospheric research

Photolysis of nitrogen oxide, nitrogen oxide/ nitrogen mixtures, and nitrogen olefin mixture

Observation of a narrow structure in p(gamma,K_s)X via interference with phi-meson production

We report observation of a narrow peak structure at ~1.54 GeV with a Gaussian width sigma=6 MeV in the missing of K_s in the reaction gamma+p = pK_sK_L. The observed structure may be due to the interference between a strange (or anti-strange) baryon resonance in the pK_L system and the phi(K_sK_L) photoproduction leading to the same final state. The statistical significance of the observed excess of events estimated as the log likelihood ratio of the resonant signal+background hypothesis and the phi-production based background only hypothesis corresponds to 5.3 sigma.Comment: Accepted for publication in Physical Review C, 9 pages, 11 figures, 1 table added, revise

Effect of substrate thermal resistance on space-domain microchannel

In recent years, Fluorescent Melting Curve Analysis (FMCA) has become an almost ubiquitous feature of commercial quantitative PCR (qPCR) thermal cyclers. Here a micro-fluidic device is presented capable of performing FMCA within a microchannel. The device consists of modular thermally conductive blocks which can sandwich a microfluidic substrate. Opposing ends of the blocks are held at differing temperatures and a linear thermal gradient is generated along the microfluidic channel. Fluorescent measurements taken from a sample as it passes along the micro-fluidic channel permits fluorescent melting curves to be generated. In this study we measure DNA melting temperature from two plasmid fragments. The effects of flow velocity and ramp-rate are investigated, and measured melting curves are compared to those acquired from a commercially available PCR thermocycler

Designing multiplayer games to facilitate emergent social behaviours online

This paper discusses an exploratory case study of the design of games that facilitate spontaneous social interaction and group behaviours among distributed individuals, based largely on symbolic presence 'state' changes. We present the principles guiding the design of our game environment: presence as a symbolic phenomenon, the importance of good visualization and the potential for spontaneous self-organization among groups of people. Our game environment, comprising a family of multiplayer 'bumper-car' style games, is described, followed by a discussion of lessons learned from observing users of the environment. Finally, we reconsider and extend our design principles in light of our observations

Application of Paleoclimatology to Coral Reef Monitoring and Management

The skeletons of reef-building corals are valuable archives of climatic and environmental information. Paleoclimatic data chiefly have been generated in areas most sensitive to global or regional climatic variability. However, these records also provide valuable information on anthropogenic influences – guidance of value to resource managers. NOAA’s Coral Reef Watch targets observations of current and past coral reef health in or near marine protected areas through satellites, in situ sensor platforms, and paleoclimatic analyses. Paleoclimatic data provide retrospective monitoring through multi-century environmental reconstructions that improve our understanding of past stress to coral reefs. Two sites in the Florida Keys National Marine Sanctuary were the first to benefit from Coral Reef Watch Program paleoenvironmental analyses. Coral cores yielded direct measurements of δ18O, δ13C, Sr/Ca, and coral skeletal growth (extension, density, and calcification) and reconstructions of reef temperatures. Temperature reconstructions were compared with instrumental data from nearby stations and global data sets, while skeletal growth was used to infer responses to changing climatic and environmental conditions. Differences between paleoclimatic data and gridded datasets demonstrated that paleodata provide more accurate estimates of reef temperatures as they sample subsurface temperatures where the corals live. Because of relatively high thermal variability, at least 12 samples per year are needed at these sites. Further work will extend these records back in time, to new locations, and expand on the data reconstructed from the skeletal archives

Polar Kerr Effect as Probe for Time-Reversal Symmetry Breaking in Unconventional Superconductors

The search for broken time reversal symmetry (TRSB) in unconventional superconductors intensified in the past year as more systems have been predicted to possess such a state. Following our pioneering study of TRSB states in Sr$_2$RuO$_4$ using magneto-optic probes, we embarked on a systematic study of several other of these candidate systems. The primary instrument for our studies is the Sagnac magneto-optic interferometer, which we recently developed. This instrument can measure magneto-optic Faraday or Kerr effects with an unprecedented sensitivity of 10 nanoradians at temperatures as low as 100 mK. In this paper we review our recent studies of TRSB in several systems, emphasizing the study of the pseudogap state of high temperature superconductors and the inverse proximity effect in superconductor/ferromagnet proximity structures.Comment: A review pape

N-Butyl­pyridine-4-thio­carboxamide

In the title mol­ecule, C10H14N2S, the n-butyl chain assumes a trans zigzag conformation. The dihedral angle between the pyridine ring and the thio­amide plane is 23.38 (8)°. The mol­ecules in the crystal structure are linked by an inter­molecular N—H⋯N hydrogen bond

Impact of internalized stigma on HIV prevention behaviors among HIV-infected individuals seeking HIV care in Kenya

In general, an initial diagnosis of HIV is likely to be correlated with the onset of HIV stigma. HIV-positive individuals are likely to internalize stigma, may suffer from psychosocial issues, or engage in maladaptive behaviors to cope with the diagnosis. Internalized stigma stems from fear of stigmatization also known as felt stigma. The current study examined the impact of HIV felt stigma on overall health and success of HIV prevention behaviors among 370 participants living with HIV and receiving care at an urban HIV clinic in Kenya. An 18-item instrument was cross culturally adapted to measure felt stigma. Descriptive and logistic regression analyses examined the data. Findings indicate that 25.9% (n=96) of participants who reported experiencing high levels of felt stigma related to other people's attitudes toward their condition, ostracizing, and a disruption of their personal life, were likely to not adhere to prescribed HIV medication and not disclose their HIV serostatus to one other person. Those who also experienced felt stigma related to a disruption of their personal lives while mediated by depression were likely to report poor overall health. Findings support having HIV clinics and interventions develop relevant HIV prevention strategies that focus on the emerging dimensions of felt stigma which can significantly impact disclosure of serostatus, medication adherence, and overall health