FISH ASSEMBLAGE STRUCTURE AND GROWTH IN THE LOWER MILK RIVER, MONTANA IN RELATION TO ENVIRONMENTAL CONDITIONS

With the major habitat alterations on the Missouri River in the 20th century, native fishes must rely more heavily on the larger, more natural, inflowing tributaries for spawning and rearing habitat. A two-year study was conducted to investigate the occurrence and abundance of fishes in the lower Milk River, Montana, which enters the Missouri River immediately below Fort Peck Dam. In sampling conducted from May to August in successive years (2002, 2003), the fish species assemblage included multiple species of special concern (blue sucker Cycleptus elongatus, paddlefish Polydon spathula, sauger Sander canadense) and multiple watch list species identified by the Montana Natural Heritage Program (burbot Lota lota, brassy minnow Hybognathus hankinsoni, plains minnow Hybognathus placitus). Relationships with environmental conditions and their interactions with temporal variables (month, year) were investigated for occurrence and total catch data. Models were generally similar for individual species with temperature and turbidity being the primary environmental conditions influencing fish occurrence and abundance. Age and growth analysis was conducted on channel catfish (Ictalurus punctatus), sauger, walleye (Sander vitreus), northern pike (Esox lucius) and shovelnose sturgeon (Scaphirhynchus platorynchus). Channel catfish, sauger, walleye and shovelnose sturgeon all grew slower and lived longer in the lower Milk River than populations at lower latitudes. In view of the lower Milk River’s role as spawning and rearing habitat for native fishes and its history of alterations from upriver dams and irrigation withdrawals, more attention should be given to maintaining or improving existing habitat conditions, including adequate instream flows and turbidity

El efecto de las áreas verdes urbanas en el desempeño académico en un contexto de pandemia

Urban green areas are known to convey peace and well-being to the people exposed to them. Because of this, many public policies consider that green areas should be included in urban planning; however, evidence indicates that not many urban centers have such areas available to them, i.e., some people living in different districts would benefit more from the positive effects of nature than others. How would this be the case for students during the pandemic? This essay presents evidence that informs us about how nature improves our quality of life and the repercussions of not being present to it. Especially in these times of pandemic, because in Lima not all districts have the same access to such areas.Las áreas verdes urbanas son conocidas por transmitir paz y bienestar a las personas expuestas a ellas. Debido a ello, las políticas públicas consideran que las áreas verdes deben estar incluidas en la planeación urbana; sin embargo, la evidencia indica que no muchos centros urbanos tienen a su disposición dichas áreas; es decir, hay personas que, por vivir en ciertos distritos, se beneficiarían más de los efectos positivos de la naturaleza que otros. ¿Cómo se daría en el caso de los estudiantes durante la pandemia? Este ensayo presenta evidencia acerca de cómo la naturaleza nos mejora la calidad de vida y las repercusiones que nos produce al no estar expuestos a ella. Especialmente en estos tiempos de pandemia, porque en Lima no todos los distritos tienen el mismo acceso a dichas áreas

Towards shoestring solutions for UK manufacturing SMEs

In the Digital Manufacturing on a Shoestring project we focus on low-cost digital solution requirements for UK manufacturing SMEs. This paper shows that many of these fall in the HRI domain while presenting the use of low-cost and off-the-shelf technologies in two demonstrators based on voice assisted production

Emission Spectroscopic Measurements with an Optical Probe in the NASA Ames IHF Arc Jet Facility

An optical probe was designed to measure radiation (from inside the arc heater) incident on a test sample immersed in the arc-heated stream. Currently, only crude estimates are available for this incident radiation. Unlike efforts of the past, where the probe line of sight was inclined to the nozzle centerline, the present development focuses on having the probe line of sight coincide with the nozzle centerline. A fiber-coupled spectrometer was used to measure the spectral distribution of incident radiation in the wavelength range of 225 to 900 nm. The radiation heat flux in this wavelength range was determined by integration of measured emission spectral intensity calibrated to incident irradiance from an integrating sphere. Two arc-heater conditions, corresponding to stream bulk enthalpy levels of 12 and 22 MJ/kg, were investigated in the 13-inch diameter nozzle of the Interaction Heating Facility at NASA Ames Research Center. With the probe placed at a distance of 10 inches from the nozzle exit plane, total radiative heat fluxes were measured to be 3.3 and 8.4 W/sq cm for the 12 and 22 MJ/kg conditions, respectively. About 17% of these radiative fluxes were due to bound-bound radiation from atoms and molecules, while the remaining 83% could be attributed to continua (bound-free and/or free-free). A comparison with spectral simulation based on CFD solutions for the arc-heater flow field and with spectroscopic measurements in the plenum region indicates that more than 95% of the measured radiation is generated in the arc region. The total radiative heat flux from the line radiation could increase by a factor of two through contributions from wavelengths outside the measured range, i.e., from the vacuum ultraviolet (wavelengths less than 225 nm) and the infrared (wavelengths greater than 900 nm). An extrapolation of the continuum radiation to these two wavelength regions was not attempted. In the tested configuration, the measured radiative heat flux accounts for only about 1.4% of the nominal heat flux on a flat face model and therefore is considered negligible. In the 6-inch diameter nozzle, on account of shorter path lengths, the radiation heat flux could be significant. Therefore, future tests in the 6-inch nozzle will have radiometers in addition to the optical probe

Tying Together Solutions for Digital Manufacturing: Assessment of Connectivity Technologies & Approaches

This paper concerns the development of low-cost solutions to address challenges in digital manufacturing (DM). Service Oriented Architectures (SOAs) are a promising approach for addressing the requirements of a low-cost DM architecture. Interaction between services in a SOA is facilitated by a connectivity technology, i.e., a framework for interoperable data exchange between heterogeneous participants. We review a variety of connectivity technologies according to their suitability for use in an SME manufacturer’s production environment, and we assess how they have been integrated into past architectures. We then provide insights into an incremental and modular architecture for manufacturing SMEs.Digital Manufacturing on a Shoestring [Digital Shoestring]. EPSRC Reference: EP/R032777/1

Mycobacteriosis in a Bull Trout from Hungry Horse Reservoir, Montana

An angler-caught bull trout (Salvelinus confluentus) from Hungry Horse Reservoir, MT with noticeably poor condition was examined to reveal liver nodules. Further investigation discovered acid-fast bacteria present in these granulomas making this a unique finding requiring further diagnostics. Molecular diagnostics revealed the infectious agent to be Mycobacterium fortuitum. This is a range and species expansion for this pathogen in fish. Further examination of additional fish from this water body did not reveal cases similar to this one, allowing for the possibility of this being a lone occurrence

Optimalni uvjeti za proizvodnju biomase i rekombinantne glicerol kinaze s pomoću kvasca Pichia pastoris

The extracellular glycerol kinase gene from Saccharomyces cerevisiae (GUT1) was cloned into the expression vector pPICZα A and integrated into the genome of the methylotrophic yeast Pichia pastoris X-33. The presence of the GUT1 insert was confirmed by PCR analysis. Four clones were selected and the functionality of the recombinant enzyme was assayed. Among the tested clones, one exhibited glycerol kinase activity of 0.32 U/mL, with specific activity of 0.025 U/mg of protein. A medium optimized for maximum biomass production by recombinant Pichia pastoris in shaker cultures was initially explored, using 2.31 % (by volume) glycerol as the carbon source. Optimization was carried out by response surface methodology (RSM). In preliminary experiments, following a Plackett-Burman design, glycerol volume fraction (φ(Gly)) and growth time (t) were selected as the most important factors in biomass production. Therefore, subsequent experiments, carried out to optimize biomass production, followed a central composite rotatable design as a function of φ(Gly) and time. Glycerol volume fraction proved to have a significant positive linear effect on biomass production. Also, time was a significant factor (at linear positive and quadratic levels) in biomass production. Experimental data were well fitted by a convex surface representing a second order polynomial model, in which biomass is a function of both factors (R²=0.946). Yield and specific activity of glycerol kinase were mainly affected by the additions of glycerol and methanol to the medium. The optimized medium composition for enzyme production was: 1 % yeast extract, 1 % peptone, 100 mM potassium phosphate buffer, pH=6.0, 1.34 % yeast nitrogen base (YNB), 4·10^–5 % biotin, 1 % methanol and 1 % glycerol, reaching 0.89 U/mL of glycerol kinase activity and 14.55 g/L of total protein in the medium after 48 h of growth.Gen za ekstracelularnu glicerol kinazu iz Saccharomyces cerevisiae (GUT1) kloniran je u ekspresijski vektor pPICZα A i integriran u genom metilotrofnog kvasca Pichia pastoris X-33. Prisutnost GUT1 potvrđena je PCR analizom. Izdvojena su četiri klona, u kojima je ispitana funkcionalnost rekombinantnog enzima. Jedan je od ispitanih klonova imao aktivnost glicerol kinaze od 0,32 U/mL i specifičnu aktivnost proteina od 0,0025 U/mg. Podloga za maksimalnu proizvodnju biomase na tresilici s pomoću rekombinantnog kvasca Pichia pastoris optimirana je uporabom glicerola, volumnog udjela od 2,31 %, kao izvora ugljika. Za optimiranje je upotrijebljena metoda odzivnih površina. U preliminarnim su ispitivanjima, primjenom Plackett-Burmanovog dizajna, određeni najvažniji čimbenici što utječu na proizvodnju biomase, a to su: volumni udio glicerola (φ(Gly)) i vrijeme uzgoja (t). Daljnji su eksperimenti provedeni radi optimiranja proizvodnje biomase, a pratili su centralno složeni dizajn kao funkciju volumnog udjela glicerola i vremena. Volumni je udio glicerola imao pozitivni linearni utjecaj na proizvodnju biomase. Vrijeme uzgoja je također bitno utjecalo (na razini linearno pozitivnih i kvadratnih zavisnosti) na proizvodnju biomase. Eksperimentalni su se podaci dobro uklapali u konveksnu funkciju koja opisuje polinom drugoga reda, u kojem je biomasa funkcija obaju faktora (R²=0,946). Prinos i specifična aktivnost glicerol kinaze ponajprije su ovisili o dodatku glicerola i metanola podlozi. Sastav optimirane podloge za proizvodnju enzima bio je: 1 % kvaščeva ekstrakta, 1 % peptona, 100 mM fosfatnog pufera (pH=6,0), 1,34 % podloge s kvascem i dušikom, 4·10^-5 % biotina, 1 % metanola i 1 % glicerola, pomoću kojih je dobivena aktivnost glicerol kinaze od 0,89 U/mL i koncentracija ukupnih proteina od 14,55 g/L u podlozi nakon 48 sati uzgoja

A declining major merger fraction with redshift in the local Universe from the largest-yet catalog of major and minor mergers in SDSS

It is difficult to accurately identify galaxy mergers and it is an even larger challenge to classify them by their mass ratio or merger stage. In previous work we used a suite of simulated mergers to create a classification technique that uses linear discriminant analysis (LDA) to identify major and minor mergers. Here, we apply this technique to 1.3 million galaxies from the SDSS DR16 photometric catalog and present the probability that each galaxy is a major or minor merger, splitting the classifications by merger stages (early, late, post-coalescence). We present publicly-available imaging predictor values and all of the above classifications for one of the largest-yet samples of galaxies. We measure the major and minor merger fraction ($f_{\mathrm{merg}}$) and build a mass-complete sample of galaxies, which we bin as a function of stellar mass and redshift. For the major mergers, we find a positive slope of $f_{\mathrm{merg}}$ with stellar mass and negative slope of $f_{\mathrm{merg}}$ with redshift between stellar masses of $10.5 < M_* (log\ M_{\odot}) < 11.6$ and redshifts of $0.03 < z < 0.19$. We are able to reproduce an artificial positive slope of the major merger fraction with redshift when we do not bin for mass or craft a complete sample, demonstrating the importance of mass completeness and mass binning. We determine that the positive trend of the major merger fraction with stellar mass is consistent with a hierarchical assembly scenario. The negative trend with redshift requires that an additional assembly mechanism, such as baryonic feedback, dominates in the local Universe.Comment: 29 pages, 22 figures, see figures 16 and 17 for a summary of the findings, accepted to MNRA