Vortex Washboard Voltage Noise in Type-II Superconductors

In order to characterize flux flow through disordered type-II superconductors, we investigate the effects of columnar and point defects on the vortex velocity / voltage power spectrum in the driven non-equilibrium steady state. We employ three-dimensional Metropolis Monte Carlo simulations to measure relevant physical observables including the force-velocity / current-voltage (I-V) characteristics, vortex spatial arrangement and structure factor, and mean flux line radius of gyration. Our simulation results compare well to earlier findings and physical intuition. We focus specifically on the voltage noise power spectra in conjunction with the vortex structure factor in the presence of weak columnar and point pinning centers. We investigate the vortex washboard noise peak and associated higher harmonics, and show that the intensity ratios of the washboard harmonics are determined by the strength of the material defects rather than the type of pins present. Through varying columnar defect lengths and pinning strengths as well as magnetic flux density we further explore the effect of the material defects on vortex transport. It is demonstrated that the radius of gyration displays quantitatively unique features that depend characteristically on the type of material defects present in the sample.Comment: Latex, 17 pages, 14 figure

FORVAL for Windows: A computer program for FORest VALuation and investment analysis

FORVAL (FORest VALuation) for Windows is a computer program for cash flow analysis of forestry investments. FORVAL was written in Visual Basic and is available from the Forest and Wildlife Research Center at Mississippi State University. We designed FORVAL to be used without a manual. It is user-friendly and includes a Windows Help file. Users enter the data requested for each box on the form and then press an appropriate button to perform the desired action

Economics of direct seeding and planting for establishing oak stands on old-field sites in the South.

On old-field sites in the South, oak stand may be established by direct seeding of acorns, or by planting seed- lings. Planting seedlings costs approximately 21/2 times the cost of direct seeding on a per acre basis, and based on our study of overall costs and returns, we conclude that in most cases the additional costs of planting are not justified by the additional benefits. Direct seeding is therefore an eco- nomically viable alternative to planting, although success with seeding requires careful selection of species/site combinations and proper seed handling and storag

Reforestation of harvested Timberlands in Mississippi: Behavior and Attitudes of Non-Industrial, Private Forest Landowners

Southern forests play an increasingly important role in the timber economy as per capita demand for wood continues to expand. Moreover, harvest restrictions in the Pacific Northwest in the early 1990s shifted a large portion of United States demand for softwoods to the South. In Mississippi, most of the forestland is owned by non-industrial private forest (NIPF) landowners. Approximately 314,000 NIPF landowners control 66 percent of the state’s forestland base (Hartsell and London 1995). The sizable acreage of timberland held by NIPF landowners nationally and in-state underscores the importance of their role in the timber economy and weighs heavily in the supply of raw material to the state’s $11.4 billion forest products industry (Munn 1998)

Remarks on the stability of the Navier-Stokes equations supplemented with stress-free boundary conditions

The purpose of this note is to analyze the long term stability of the Navier-Stokes equations supplemented with the Coriolis force and the stress-free boundary condition. It is shown that, if the flow domain is axisymmetric, spurious stability behaviors can occur depending whether the Coriolis force is active or not

Adenoviral-Vectored Centralized Consensus Hemagglutinin Vaccine Provides Broad Protection against H2 Influenza a Virus

Several influenza pandemics have occurred in the past century, one of which emerged in 1957 from a zoonotic transmission of H2N2 from an avian reservoir into humans. This pandemic caused 2–4 million deaths and circulated until 1968. Since the disappearance of H2N2 from human populations, there has been waning immunity against H2, and this subtype is not currently incorporated into seasonal vaccines. However, H2 influenza remains a pandemic threat due to consistent circulation in avian reservoirs. Here, we describe a method of pandemic preparedness by creating an adenoviral-vectored centralized consensus vaccine design against human H2 influenza. We also assessed the utility of serotype-switching to enhance the protective immune responses seen with homologous prime-boosting strategies. Immunization with an H2 centralized consensus showed a wide breadth of antibody responses after vaccination, protection against challenge with a divergent human H2 strain, and significantly reduced viral load in the lungs after challenge. Further, serotype switching between two species C adenoviruses enhanced protective antibody titers after heterologous boosting. These data support the notion that an adenoviral-vectored H2 centralized consensus vaccine has the ability to provide broadly cross-reactive immune responses to protect against divergent strains of H2 influenza and prepare for a possible pandemic

Efficacy of a T Cell-Biased Adenovirus Vector as a Zika Virus Vaccine

Zika virus (ZIKV) is a major public health concern due to the risk of congenital Zika syndrome in developing fetuses and Guillain-Barre syndrome in adults. Currently, there are no approved vaccines available to protect against infection. Adenoviruses are safe and highly immunogenic vaccine vectors capable of inducing lasting humoral and cellular immune responses. Here, we developed two Adenovirus (Ad) vectored Zika virus vaccines by inserting a ZIKV prM-E gene expression cassette into human Ad types 4 (Ad4-prM-E) and 5 (Ad5-prM-E). Immune correlates indicate that Ad5-prM-E vaccination induces both an anti-ZIKV antibody and T-cell responses whereas Ad4-prM-E vaccination only induces a T-cell response. In a highly lethal challenge in an interferon α/β receptor knockout mice, 80% of Ad5 vaccinated animals and 33% of Ad4 vaccinated animals survived a lethal ZIKV challenge, whereas no animals in the sham vaccinated group survived. In an infection model utilizing immunocompetent C57BL/6 mice that were immunized and then treated with a blocking anti-IFNAR-1 antibody immediately before ZIKV challenge, 100% of Ad4-prM-E and Ad5-prM-E vaccinated mice survived. This indicates that Ad4-prM-E vaccination is protective without the development of detectable anti-ZIKV antibodies. The protection seen in these highly lethal mouse models demonstrate the efficacy of Ad vectored vaccines for use against ZIKV

Epigraph hemagglutinin vaccine induces broad cross-reactive immunity against swine H3 influenza virus

Influenza A virus infection in swine impacts the agricultural industry in addition to its zoonotic potential. Here, we utilize epigraph, a computational algorithm, to design a universal swine H3 influenza vaccine. The epigraph hemagglutinin proteins are delivered using an Adenovirus type 5 vector and are compared to a wild type hemagglutinin and the commercial inactivated vaccine, FluSure. In mice, epigraph vaccination leads to significant cross-reactive antibody and T-cell responses against a diverse panel of swH3 isolates. Epigraph vaccination also reduces weight loss and lung viral titers in mice after challenge with three divergent swH3 viruses. Vaccination studies in swine, the target species for this vaccine, show stronger levels of cross-reactive antibodies and T-cell responses after immunization with the epigraph vaccine compared to the wild type and FluSure vaccines. In both murine and swine models, epigraph vaccination shows superior cross-reactive immunity that should be further investigated as a universal swH3 vaccine

Directional Microwave Emission from Femtosecond-laser Illuminated Linear Arrays of Superconducting Rings

We examine the electromagnetic emission from two photo-illuminated linear arrays composed of inductively charged superconducting ring elements. The arrays are illuminated by an ultrafast infrared laser that triggers microwave broadband emission detected in the 1–26 GHz range. Based on constructive interference from the arrays a narrowing of the forward radiation lobe is observed with increasing element count and frequency demonstrating directed GHz emission. Results suggest that higher frequencies and a larger number of elements are achievable leading to a unique pulsed array emitter concept that can span frequencies from the microwave to the terahertz (THz) regime