Synthesis and Application of Cellulose-Based Hydrogels for Anti-Biofouling in Marine Environments

Biofouling is a ubiquitous natural phenomenon that incurs major costs and damages to marine-based industries and infrastructure worldwide. While antibiofouling agents do exist, these contain toxic biocides and metals which are harmful to non-target organisms and the local ecosystem. This research aimed to create a renewably sourced, non-toxic hydrogel with antibiofouling properties in a marine environment. Hydrogels were made using functionalized CMC, a cellulose derivative, crosslinked with dithiol molecules. It was shown that the mechanical properties and swelling abilities of hydrogels could be controlled by making the hydrogels at a particular thiol to norbornene ratio. Hydrogels made with one of the crosslinkers also demonstrated the ability to have a tunable degradation rate in a marine environment. Ultimately, it was shown that hydrogels tested failed to remove settled foulants

Internal Energy Distribution in Electrospray Ionization from the Multiple-Collision Model: The case of a Thermal-Like Distribution

In the presented study, the ion survival yields of the theoretical mass spectra simulated by the MassKinetic software are fitted with the experimental ion survival yield of substituted benzylpyridinium cations reported in a precedent paper (J. Mass Spectrom. 1999, 34, 1373-1379). A partially elastic multiple collision model is considered for describing the ion behaviour into the desolation area of the ESI source. The adjusting parameters are not the shape and the position of the P(Eint) curve but rather parameters related to the source acting, such as the pressure and the kinetic energy of ions entering the desolvation zone. In the case of a PE SCIEX ESI source interfaced with a quadrupole mass spectrometer, the energy uptake can then be well-defined by considering the case of a thermal-like distribution an average number of “effective” collisions of 29. From this model, it’s possible to correlate the voltage values applied on the orifice of the desolvation area to initial kinetic energy of ions entering into the collision zone of the ESI source. In the present case, these theoretical initial kinetic energy values range from 5.5 to 9 eV and the results of calculations shown also that the mean internal energy increases linearly with the orifice voltage. This modelling allows defining the internal energy distribution of ions in different part of the ESI source. The activation conditions occurring into the studied ESI source can be compared to a warm-up of ions. Indeed, the internal energy distributions resemble to thermal distribution of ions having a “characteristic temperature” (Tchar) parameter between 1020 to 1550 K. In addition, this study evidences a linear correlation between and Tchar. The slope value of this curve can be related to a calorimetric parameter such as the heat capacity of the activated substituted benzytlpyridinium cations

Inhibition of the Host Translation Shutoff Response by Herpes Simplex Virus 1 Triggers Nuclear Envelope-Derived Autophagy

Macroautophagy is a cellular pathway that degrades intracellular pathogens and contributes to antigen presentation. Herpes simplex virus 1 (HSV-1) infection triggers both macroautophagy and an additional form of autophagy that uses the nuclear envelope as a source of membrane. The present study constitutes the first in-depth analysis of nuclear envelope-derived autophagy (NEDA). We established LC3a as a marker that allowed us to distinguish between NEDA and macroautophagy in both immunofluorescence and flow cytometry. NEDA was observed in many different cell types, indicating that it is a general response to HSV-1 infection. This autophagic pathway is known to depend on the viral protein γ34.5, which can inhibit macroautophagy via binding to beclin-1. Using mutant viruses, we were able to show that binding of beclin-1 by γ34.5 had no effect on NEDA, demonstrating that NEDA is regulated differently than macroautophagy. Instead, NEDA was triggered in response to γ34.5 binding to protein phosphatase 1α, an interaction used by the virus to prevent host cells from shutting off protein translation. NEDA was not triggered when late viral protein production was inhibited with acyclovir or hippuristanol, indicating that the accumulation of these proteins might stress infected cells. Interestingly, expression of the late viral protein gH was sufficient to rescue NEDA in the context of infection with a virus that otherwise does not support strong late viral protein expression. We argue that NEDA is a cellular stress response triggered late during HSV-1 infection and might compensate for the viral alteration of the macroautophagic response

Noxious weed monitoring at the U.S. Air Force Academy: year 6 results

Prepared for: U.S. Air Force Academy, Dept. of Natural Resources.April 2011.Includes bibliographical references

Conservation blueprint for neotropical migratory birds in western Colorado, A

Final report submitted to the United States Fish and Wildlife Service (Neotropical Migratory Bird Act).December 2007.Includes bibliographical references

Development and refinement of Rel@x : a training in hypnosis-derived communication for pediatric nurses to prevent procedural pain

IntroductionStudies in pediatric oncology have shown that hypnosis effectively reduces patients’ pain and distress during painful procedures. This remains underutilized in the healthcare system due to the staff cost and availability of hypnotherapists. To develop the use of hypnosis-derived communication, we aimed to train nurses to use hypnosis-derived communication while they perform painful procedures. ObjectivesThis study aimed to (1) develop a brief training in hypnosis-derived communication for pediatric nurses named Rel@x, (2) pretest the training with experienced pediatric oncology nurses, and (3) refine the training based on nurses’ suggestions. MethodsThe Rel@x training consists of two 4-h sessions: one related to relational aspects and another one presenting one of two selected hypnotic communication techniques (“pleasant place” or “magic glove”). Rel@x makes use of manuals, cue card reminders, visual aids, videos, and an e-learning platform. To refine Rel@x, a complete training cycle was conducted with seven female pediatric oncology nurses. A mixed method study with an evaluation questionnaire and a post-training focus group interview was conducted. ResultsQuantitative data showed that nurses overall positively rated the training program: relevance and acceptability (median average of 5.4/6); use of hypnotic communication (median average of 5.2/6); expected effects (median average of 5.4/6); program implementation (5.6/6). Two general themes emerged from the qualitative data: perceptions of hypnotic communication and the evaluation of the Rel@x training program. Based on nurses’ suggestions, Rel@x was refined by adding more practical components, more time for practice, more time between the two sessions and additional tools (cue card reminders, keywords, virtual e-learning recap module). Conclusion and clinical implicationsThe use of hypnosis-derived communication during painful procedures and the Rel@x training were viewed favorably amongst pediatric nurses. Rel@x offers a complete training in hypnosis-derived communication for pediatric nurses. This training fosters the optimal use of hypnosis-derived communication during care and may significantly reduce children’s procedural pain and distress

Phase diagram of insulating crystal and quantum Hall states in ABC-stacked trilayer graphene

In the presence of a perpendicular magnetic field, ABC-stacked trilayer graphene's chiral band structure supports a 12-fold degenerate N=0 Landau level (LL). Along with the valley and spin degrees of freedom, the zeroth LL contains additional quantum numbers associated with the LL orbital index $$. Remote inter-layer hopping terms and external potential difference $\Delta_{B}$ between the layers lead to LL splitting by introducing a gap $$ between the degenerate zero-energy triplet LL orbitals. Assuming that the spin and valley degrees of freedom are frozen, we study the phase diagram of this system resulting from competition of the single particle LL splitting and Coulomb interactions within the Hartree-Fock approximation at integer filling factors. Above a critical value $\Delta_{LL}^{c}$ of the external potential difference i,e, for $|\Delta_{LL}| >\Delta_{LL}^{c}$, the ground state is a uniform quantum Hall state where the electrons occupy the lowest unoccupied LL orbital index. For $|\Delta_{LL}| <\Delta_{LL}^{c}$ (which corresponds to large positive or negative values of $\Delta_{B}$) the uniform QH state is unstable to the formation of a crystal state at integer filling factors. This phase transition should be characterized by a Hall plateau transition as a function of $\Delta_{LL}$ at a fixed filling factor. We also study the properties of this crystal state and discuss its experimental detection.Comment: 16 pages with 13 figure

Fabrication of an autonomously self-healing flexible thin-film capacitor by slot-die coating

Flexible pressure sensors with self-healing abilities for wearable electronics are being developed, but generally either lack autonomous self-healing properties or require sophisticated material processing methods. To address this challenge, we developed flexible, low-cost and autonomously self-healing capacitive sensors using a crosslinked poly(dimethylsiloxane) through metal-ligand interactions processed into thin films via slot-die coating. These films have excellent self-healing properties, approximately 1.34 × 105 μm3 per hour at room temperature and 2.87 × 105 μm3 per hour at body temperature (37 °C). Similarly, no significant change in capacitance under bending strain was observed on these flexible thin-films when assembled on poly(ethyleneterephthalate) (PET) substrates; capacitors showed good sensitivity at low pressure regimes. More importantly, the devices fully recovered their sensitivity after being damaged and healed, which is directly attributed to the rapid and autonomous self-healing of the dielectric materials

Noxious weed monitoring at the U.S. Air Force Academy: year 5 results

Prepared for: U.S. Air Force Academy, Dept. of Natural Resources.March, 2010.Includes bibliographical references