40 research outputs found
Benefits of undergraduate participation in faculty research in natural resources
Graduate student assistance with faculty research is common in university natural resource programs. Traditionally, undergraduate students are involved less with research programs of faculty. The Uintah Basin Branch Campus of Utah State University provides a unique setting for developing research projects in natural resources that involve undergraduates. We use a research project on the control of greasewood (Sarcobatus vermiculatus) iin the Book Cliffs, Utah to illustrate the benefits and challenges for undergraduate students and faculty of collaboration on research. Students benefit by interacting with faculty outside the classroom; by applying classroom learning to field problems; and by working with natural resource management personnel. Faculty benefit by observing the ability of students to apply classroom learning to field situations; by maintaining a scholarly research program; and by interacting with students outside the classroom
Self-aligning planarization and passivation for integration applications in III-V semiconductor devices
Cataloged from PDF version of article.This paper reports an easy planarization and passivation approach for the integration of III-V semiconductor devices. Vertically etched III-V semiconductor devices typically require sidewall passivation to suppress leakage currents and planarization of the passivation material for metal interconnection and device integration. It is, however, challenging to planarize all devices at once. This technique offers wafer-scale passivation and planarization that is automatically leveled to the device top in the 1-3-mum vicinity surrounding each device. In this method, a dielectric hard mask is used to define the device area. An undercut structure is intentionally created below the hard mask, which is retained during the subsequent polymer spinning and anisotropic polymer etch back., The spin-on polymer that fills in the undercut seals the sidewalls for all the devices across the wafer. After the polymer etch back, the dielectric mask is removed leaving the polymer surrounding each device level with its device top to atomic scale flatness. This integration method is robust and is insensitive to spin-on polymer thickness, polymer etch nonuniformity, and device height difference. It prevents the polymer under the hard mask from etch-induced damage and creates a polymer-free device surface for metallization upon removal of the dielectric mask. We applied this integration technique in fabricating an InP-based photonic switch that consists of a mesa photodiode and a quantum-well waveguide modulator using benzocyclobutene (BCB) polymer. We demonstrated functional integrated photonic switches with high process yield of >90%, high breakdown voltage of >25 V, and low ohmic contact resistance of similar to 10 Omega. To the best of our knowledge, such an integration of a surface-normal photodiode and a lumped electroabsorption modulator with the use of BCB is the first to be implemented on a single substrate
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Neutrophil-to-Lymphocyte and Platelet-to-Lymphocyte Ratios as Prognostic Inflammatory Biomarkers in Human Immunodeficiency Virus (HIV), Hepatitis C Virus (HCV), and HIV/HCV Coinfection.
Background:Inflammation in human immunodeficiency virus (HIV)-infected patients is associated with poorer health outcomes. Whether inflammation as measured by the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) adds information to existing prognostic indices is not known. Methods:We analyzed data from 2000 to 2012 in the Veterans Aging Cohort Study (VACS), overall and stratified by HIV/hepatitis C virus status (n = 89 786). We randomly selected a visit date at which all laboratory values of interest were available within 180 days; participants with HIV received at least 1 year of antiretroviral therapy. We followed patients for (1) mortality and (2) hepatic decompensation (HD) and analyzed associations using Cox regression, adjusted for a validated mortality risk index (VACS Index 2.0). In VACS Biomarker Cohort, we considered correlation with biomarkers of inflammation: interleukin-6, D-dimer, and soluble CD-14. Results:Neutrophil-to-lymphocyte ratio and PLR demonstrated strong unadjusted associations with mortality (P < .0001) and HD (P < .0001) and were weakly correlated with other inflammatory biomarkers. Although NLR remained statistically independent for mortality, as did PLR for HD, the addition of NLR and PLR to the VACS Index 2.0 did not result in significant improvement in discrimination compared with VACS Index 2.0 alone for mortality (C-statistic 0.767 vs 0.758) or for HD (C-statistic 0.805 vs 0.801). Conclusions:Neutrophil-to-lymphocyte ratio and PLR were strongly associated with mortality and HD and weakly correlated with inflammatory biomarkers. However, most of their association was explained by VACS Index 2.0. Addition of NLR and PLR to VACS 2.0 did not substantially improve discrimination for either outcome
Toxic equivalency factors (TEFs) for PCBs, PCDDs, PCDFs for humans and wildlife.
An expert meeting was organized by the World Health Organization (WHO) and held in Stockholm on 15-18 June 1997. The objective of this meeting was to derive consensus toxic equivalency factors (TEFs) for polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and dioxinlike polychlorinated biphenyls (PCBs) for both human, fish, and wildlife risk assessment. Based on existing literature data, TEFs were (re)evaluated and either revised (mammals) or established (fish and birds). A few mammalian WHO-TEFs were revised, including 1,2,3,7,8-pentachlorinated DD, octachlorinated DD, octachlorinated DF, and PCB 77. These mammalian TEFs are also considered applicable for humans and wild mammalian species. Furthermore, it was concluded that there was insufficient in vivo evidence to continue the use of TEFs for some di-ortho PCBs, as suggested earlier by Ahlborg et al. [Chemosphere 28:1049-1067 (1994)]. In addition, TEFs for fish and birds were determined. The WHO working group attempted to harmonize TEFs across different taxa to the extent possible. However, total synchronization of TEFs was not feasible, as there were orders of a magnitude difference in TEFs between taxa for some compounds. In this respect, the absent or very low response of fish to mono-ortho PCBs is most noticeable compared to mammals and birds. Uncertainties that could compromise the TEF concept were also reviewed, including nonadditive interactions, differences in shape of the dose-response curve, and species responsiveness. In spite of these uncertainties, it was concluded that the TEF concept is still the most plausible and feasible approach for risk assessment of halogenated aromatic hydrocarbons with dioxinlike properties
A call for action: Improve reporting of research studies to increase the scientific basis for regulatory decision-making
Publisher's version (Ăștgefin grein)This is a call for action to scientific journals to introduce reporting requirements for toxicity and ecotoxicity studies. Such reporting requirements will support the use of peerâreviewed research studies in regulatory decisionâmaking. Moreover, this could improve the reliability and reproducibility of published studies in general and make better use of the resources spent in research.Nordic Council of Minister
Woodrow Wilsonâs diplomatic agenda and strategic military interventions: how they affected the Russian Civil War 1918-1920
This thesis aims to understand the factors that affected Woodrow Wilsonâs foreign and military policy actions, which subsequently led to decisions that dictated United Statesâ intervention into the Russian Civil War, 1918-1920. The background information discussed demonstrates the importance of the Russian Civil War. This chaotic time in history surrounding World War I caused much of Woodrow Wilsonâs dilemma and consequentially changed future of Soviet-American relations. It details how it would take numerous foreign policy shifts to convince Mr. Wilson to send U.S. troops to intervene into North Russia and Siberia. Leninâs opposing perspective will encompass what is contained in much of the supporting information surrounding this thesis. In conjunction with military operations there, the allies attempted to broker peace with Lenin and the Bolsheviks in the form of the Prinkipo Proposal, the Bullitt Mission, and the Hoover-Nansen Proposal. The concluding question that frames the argument of this research will answer what happened because Wilson intervened on Russian soil and how it affected the Communist world revolution. What positive results, if any, can be discovered? (Author abstract)Rinehart, R.A. (2017) Woodrow Wilsonâs diplomatic agenda and strategic military interventions: how they affected the Russian Civil War 1918-1920. Retrieved from http://academicarchive.snhu.eduMaster ArtsHistoryCollege of Online and Continuing Educatio