Epidemiological Investigations of Bighorn Sheep Respiratory Disease and Implications for Management

Infectious respiratory disease has long been identified as the cause of bighorn sheep (Ovis canadensis) historical declines and extirpations, and Mycoplasma ovipneumoniae (Movi) is the primary pathogen inducing disease and mortality. Population-level effects of pneumonia events range from mild to extirpation. Variable individual response to pathogen exposure emerges from dynamic interactions between competing evolutionary processes within the host and pathogen. Understanding impacts of this evolutionary warfare is essential to assessing long-term impacts of pathogen invasion and developing appropriate countermeasures to protect population health. Freeranging populations are faced with spillover infections from domestic sheep and goats as well as previously infected conspecifics. The introduction of a novel Movi strain from a spillover event can result in high all-age morbidity and subsequent mortality. We studied the effects of indirect and direct infection of captive bighorn sheep with Movi, a genetically diverse pathogen. We also used known Movi-carriage histories to classify ewes into 1 of 3 Movi carrier classes. We tested the hypothesis that respiratory disease persistence within bighorn sheep populations is driven by chronically Movi infected ewes, and the prediction that lambs born in pens with at least one chronic carrier ewe (treatment) would experience Movi-induced pneumonia mortality whereas lambs born in pens without a chronic carrier ewe (control) would not develop fatal pneumonia. When all mortality causes were pooled across all years of our study, the percentage of lambs that did not survive was more than twice as high when lambs were in born in pens containing at least one Movi chronic shedder ewe (treatment), compared to when only Movi negative and/or intermittent ewes were present in the pen (control; 92% (n = 33 of 36) and 38% (n = 5 of 13). The mean probability of pneumonia-induced mortality for commingled lambs was above 0.75 by 15 days of age and generally remained above that level for the duration of the study. Our model also estimated this probability to be elevated (≥ 0.90) as early as 16 days of age until 45 days of age, and a secondary peak for older, nearly weaned, lambs (105–114 days of age). While conducting a study for Movi detection probability in serial samples, we document unilateral Movi colonization and direct managers on field sampling techniques for reliable disease surveillance of bighorn sheep populations. Our results suggest that active disease control efforts must account for multiple Movi strains to prevent spillover epidemics. Our results also underscore that removal of chronic carriers from a population will aid bighorn sheep recovery efforts

Nickel hydrogen low Earth orbit test program update and status

The current status of nickel-hydrogen (NiH2) testing ongong at NWSC, Crane In, and The Aerospace Corporation, El Segundo, Ca are described. The objective of this testing is to develop a database for NiH2 battery use in Low Earth Orbit (LEO) and support applications in Medium Altitude Orbit (MAO). Individual pressure vessel-type cells are being tested. A minimum of 200 cells (3.5 in diameter and 4.5 in diameter) are included in the test, from four U.S. vendors. As of this date (Nov. 18, 1986) approximately 60 cells have completed preliminary testing (acceptance, characterization, and environmental testing) and have gone into life cycling

Student and Faculty Perceptions of the Impact of Masks on Student Learning and Communication in the Classroom

As a result of the COVID-19 pandemic, facemask requirements while indoors were implemented in colleges and universities, both in the United States and beyond. Empirical evidence has shown that such mandates improved the health and safety of students, faculty, staff, and administrators. However, the impacts of such precautions on student learning and communication have to date gone largely unexplored. The current study surveyed students and faculty at one regional midwestern institution to assess their perceptions on the impact of masks on student learning and communication in the classroom. Findings are included, followed by a discussion of their implications

The Upper Respiratory Tract as a Microbial Source for Pulmonary Infections in Cystic Fibrosis. Parallels from Island Biogeography

A continuously mixed series of microbial communities inhabits various points of the respiratory tract, with community composition determined by distance from colonization sources, colonization rates, and extinction rates. Ecology and evolution theory developed in the context of biogeography is relevant to clinical microbiology and could reframe the interpretation of recent studies comparing communities from lung explant samples, sputum samples, and oropharyngeal swabs. We propose an island biogeography model of the microbial communities inhabiting different niches in human airways. Island biogeography as applied to communities separated by time and space is a useful parallel for exploring microbial colonization of healthy and diseased lungs, with the potential to inform our understanding of microbial community dynamics and the relevance of microbes detected in different sample types. In this perspective, we focus on the intermixed microbial communities inhabiting different regions of the airways of patients with cystic fibrosis

Nanophotonic Neural Probes for in vivo Light Sheet Imaging

We present implantable silicon neural probes with nanophotonic waveguide routing networks and grating emitters for light sheet imaging. Fluorescein beam profiles, fluorescent bead imaging, and fluorescence brain imaging in vivo are presented

Multicomponent systems with cyclodextrins and hydrophilic polymers for the delivery of Efavirenz

AbstractEfavirenz (EFZ) is one of the most used drugs in the treatment of AIDS and is the first antiretroviral choice. However, since it has low solubility, it does not exhibit suitable bioavailability, which interferes with its therapeutic action and is classified as a class II drug according Biopharmaceutical Classification System (low solubility and high permeability). Among several drug delivery systems, the multicomponent systems with cyclodextrins and hydrophilic polymers are a promising alternative for increasing the aqueous solubility of the drug. The present study aimed to develop and characterize in a ternary system of EFZ, MβCD and PVP K30. The results showed that the solid ternary system provided a large increase in the dissolution rate which was greater than 80% and was characterized by DSC, TG, XRD, FT-IR and SEM. The use of the ternary system (EFZ, MβCD and PVP K30 1%) proved to be a viable, effective and safe delivery of the drug. The addition of the hydrophilic polymer appeared to be suitable for the development of a solid oral pharmaceutical product, with possible industrial scale-up and with low concentration of CDs (cyclodextrins)

Nanophotonic Neural Probes for in vivo Light Sheet Imaging

We present implantable silicon neural probes with nanophotonic waveguide routing networks and grating emitters for light sheet imaging. Fluorescein beam profiles, fluorescent bead imaging, and fluorescence brain imaging in vivo are presented

Beam-Steering Nanophotonic Phased-Array Neural Probes

We demonstrate the first implantable nanophotonic neural probes with integrated silicon nitride phased arrays. Coherent beam-steering is achieved in brain tissue by wavelength tuning. Beam profiles, optogenetic stimulation, and functional imaging are validated in vitro

Implantable photonic neural probes for light-sheet fluorescence brain imaging

Significance: Light-sheet fluorescence microscopy (LSFM) is a powerful technique for highspeed volumetric functional imaging. However, in typical light-sheet microscopes, the illumination and collection optics impose significant constraints upon the imaging of non-transparent brain tissues. We demonstrate that these constraints can be surmounted using a new class of implantable photonic neural probes. Aim: Mass manufacturable, silicon-based light-sheet photonic neural probes can generate planar patterned illumination at arbitrary depths in brain tissues without any additional micro-optic components. Approach: We develop implantable photonic neural probes that generate light sheets in tissue. The probes were fabricated in a photonics foundry on 200-mm-diameter silicon wafers. The light sheets were characterized in fluorescein and in free space. The probe-enabled imaging approach was tested in fixed, in vitro, and in vivo mouse brain tissues. Imaging tests were also performed using fluorescent beads suspended in agarose. Results: The probes had 5 to 10 addressable sheets and average sheet thicknesses <16 μm for propagation distances up to 300 μm in free space. Imaging areas were as large as ≈240 μm × 490 μm in brain tissue. Image contrast was enhanced relative to epifluorescence microscopy. Conclusions: The neural probes can lead to new variants of LSFM for deep brain imaging and experiments in freely moving animals