Modelling the Species Distribution of Flat-Headed Cats (Prionailurus planiceps), an Endangered South-East Asian Small Felid

PubMed Central

Hearn, Andrew J.; Hesse, Deike; Mohamed, Azlan; Traeholdt, Carl; Cheyne, Susan M.; Sunarto, Sunarto; Jayasilan, Mohd-Azlan; Ross, Joanna; Shapiro, Aurélie C.; Sebastian, Anthony; Dech, Stefan; Breitenmoser, Christine; Sanderson, Jim; Duckworth, J. W.; Hofer, Heribert

2010-01-01

Background The flat-headed cat (Prionailurus planiceps) is one of the world's least known, highly threatened felids with a distribution restricted to tropical lowland rainforests in Peninsular Thailand/Malaysia, Borneo and Sumatra. Throughout its geographic range large-scale anthropogenic transformation processes, including the pollution of fresh-water river systems and landscape fragmentation, raise concerns regarding its conservation status. Despite an increasing number of camera-trapping field surveys for carnivores in South-East Asia during the past two decades, few of these studies recorded the flat-headed cat. Methodology/Principal Findings In this study, we designed a predictive species distribution model using the Maximum Entropy (MaxEnt) algorithm to reassess the potential current distribution and conservation status of the flat-headed cat. Eighty-eight independent species occurrence records were gathered from field surveys, literature records, and museum collections. These current and historical records were analysed in relation to bioclimatic variables (WorldClim), altitude (SRTM) and minimum distance to larger water resources (Digital Chart of the World). Distance to water was identified as the key predictor for the occurrence of flat-headed cats (>50% explanation). In addition, we used different land cover maps (GLC2000, GlobCover and SarVision LLC for Borneo), information on protected areas and regional human population density data to extract suitable habitats from the potential distribution predicted by the MaxEnt model. Between 54% and 68% of suitable habitat has already been converted to unsuitable land cover types (e.g. croplands, plantations), and only between 10% and 20% of suitable land cover is categorised as fully protected according to the IUCN criteria. The remaining habitats are highly fragmented and only a few larger forest patches remain. Conclusion/Significance Based on our findings, we recommend that future conservation efforts for the flat-headed cat should focus on the identified remaining key localities and be implemented through a continuous dialogue between local stakeholders, conservationists and scientists to ensure its long-term survival. The flat-headed cat can serve as a flagship species for the protection of several other endangered species associated with the threatened tropical lowland forests and surface fresh-water sources in this region. PMID:20305809

Modelling the species distribution of flat-headed cats (Prionailurus planiceps), an endangered South-East Asian small felid.

PubMed

Wilting, Andreas; Cord, Anna; Hearn, Andrew J; Hesse, Deike; Mohamed, Azlan; Traeholdt, Carl; Cheyne, Susan M; Sunarto, Sunarto; Jayasilan, Mohd-Azlan; Ross, Joanna; Shapiro, Aurélie C; Sebastian, Anthony; Dech, Stefan; Breitenmoser, Christine; Sanderson, Jim; Duckworth, J W; Hofer, Heribert

2010-03-17

The flat-headed cat (Prionailurus planiceps) is one of the world's least known, highly threatened felids with a distribution restricted to tropical lowland rainforests in Peninsular Thailand/Malaysia, Borneo and Sumatra. Throughout its geographic range large-scale anthropogenic transformation processes, including the pollution of fresh-water river systems and landscape fragmentation, raise concerns regarding its conservation status. Despite an increasing number of camera-trapping field surveys for carnivores in South-East Asia during the past two decades, few of these studies recorded the flat-headed cat. In this study, we designed a predictive species distribution model using the Maximum Entropy (MaxEnt) algorithm to reassess the potential current distribution and conservation status of the flat-headed cat. Eighty-eight independent species occurrence records were gathered from field surveys, literature records, and museum collections. These current and historical records were analysed in relation to bioclimatic variables (WorldClim), altitude (SRTM) and minimum distance to larger water resources (Digital Chart of the World). Distance to water was identified as the key predictor for the occurrence of flat-headed cats (>50% explanation). In addition, we used different land cover maps (GLC2000, GlobCover and SarVision LLC for Borneo), information on protected areas and regional human population density data to extract suitable habitats from the potential distribution predicted by the MaxEnt model. Between 54% and 68% of suitable habitat has already been converted to unsuitable land cover types (e.g. croplands, plantations), and only between 10% and 20% of suitable land cover is categorised as fully protected according to the IUCN criteria. The remaining habitats are highly fragmented and only a few larger forest patches remain. Based on our findings, we recommend that future conservation efforts for the flat-headed cat should focus on the identified remaining key localities and be implemented through a continuous dialogue between local stakeholders, conservationists and scientists to ensure its long-term survival. The flat-headed cat can serve as a flagship species for the protection of several other endangered species associated with the threatened tropical lowland forests and surface fresh-water sources in this region.

75 FR 19989 - Final Environmental Impact Statement for Drought Management Planning at the Kerr Hydroelectric...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-16

... Drought Management Planning at the Kerr Hydroelectric Project, Flathead Lake, MT AGENCY: Bureau of Indian... Impact Statement (FEIS) for Drought Management Planning at the Kerr Hydroelectric Project, Flathead Lake... drought management planning at the Kerr Hydroelectric Project no sooner than 30 days following the...

US 93 North post-construction wildlife-vehicle collision and wildlife crossing monitoring on the Flathead Indian reservation between Evaro and Polson, Montana : final report.

DOT National Transportation Integrated Search

2016-12-01

The US Highway 93 North reconstruction project on the Flathead Indian Reservation in northwest Montana represents one of the most extensive wildlife-sensitive highway design efforts to date in North America. The reconstruction of the 56 mile (90 km) ...

Evaluation of a single application of Neonicotnoid and multi-application contact insecticides for flatheaded borer management in field grown Acer rubrum L. cultivars

USDA-ARS?s Scientific Manuscript database

Two trials evaluated insecticides for flatheaded borer (Chrysobothris femorata [Olivier]) control and red maple (Acer rubrum L.) cultivar growth over a 4-year period. Soil-applied systemic insecticides (acephate, imidacloprid, clothianidin, dinotefuran, and thiamethoxam) and trunk-applied contact i...

Depth and substrate as determinants of distribution of juvenile flathead sole (Hippoglossoides elassodon) and rock sole (Pleuronectes bilineatus), in Kachemak Bay, Alaska

USGS Publications Warehouse

Abookire, Alisa A.; Norcross, Brenda L.

1998-01-01

Three transects in Kachemak Bay, Alaska, were sampled in September 1994, May and August 1995, and February, May, and August 1996. Juvenile flathead sole, Hippoglossoides elassodon, and rock sole, Pleuronectes bilineatus, were the most abundant flatfishes, comprising 65-85% of all fiatfishes captured at any period. Collections of fish and sediments were made at regular depth contour intervals of l0 m. Habitat distribution was described by depth at 10 m increments and sediment percent weights of gravel, sand, and mud. Year-round habitat of flathead sole age-0 was primarily from 40 to 60 m, and age-1 habitat was primarily from 40 to 80 m. Summer habitat of rock sole age-0 and -1 was from 10 to 30 m, and in winter they moved offshore to depths of up to 150 m. Both age classes of flathead sole were most abundant on mixed mud sediments, while age-1 were also in high abundance on muddy sand sediments. Rock sole age-0 and -1 were most abundant on sand, though age-1 were also found on a variety of sediments both finer and coarser grained than sand. Flathead sole and rock sole had distinctive depth and sediment habitats. When habitat overlap occurred between the species, it was most often due to rock sole moving offshore in the winter. Abundances were not significantly different among seasons for age-1 flatfishes.

75 FR 76352 - Fisheries of the Exclusive Economic Zone Off Alaska; Gulf of Alaska; Proposed 2011 and 2012...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-08

... for 2011 and 2012 that are equal to proposed ABCs for pollock, deep-water flatfish, rex sole... certain species: Pacific cod, flathead sole, shallow-water flatfish, arrowtooth flounder, and other... that the ABC is not exceeded. The flathead sole, shallow-water flatfish, and arrowtooth flounder TACs...

Isolation and identification of mosquito (Aedes aegypti) biting- deterrent compounds from the native American ethnobotanical remedy plant Hierochloë odorata (Sweetgrass)

USDA-ARS?s Scientific Manuscript database

Ethnopharmacological relevance: Hierochloë odorata (L.) P. Beauv. (Poaceae), commonly known as sweetgrass, has documented use as an insect repellent by the Flatheads of Montana and Blackfoot of Alberta. Both the Flatheads of Montana and Blackfoot of Alberta would use braided plant material in a sac...

Earth observations taken by the Expedition Seven crew

NASA Image and Video Library

2003-08-02

ISS007-E-11612 (2 August 2003) --- This digital still camera's view of Glacier National Park in Montana, was captured by one of the crew members aboard the International Space Station orbiting earth at 215 nautical miles. The area pictured is north of Flathead Lake on the southern flank of the Apgar Mountains, just across the Flathead River.

Tests with DDT foliar sprays to control the California flatheaded borer

Treesearch

Robert L. Lyon

1959-01-01

The California flatheaded borer (Melanophila californica Van Dyke) kills an estimated 30 million board-feet of pine timber in California each year. The insect is especially troublesome on ponderosa and Jeffrey pines growing on dry sites, and it has caused serious losses in Jeffrey pine stands on valuable , watershed and recreational lands of...

Collective Bargaining Agreement between Flathead Valley Community College Board of Trustees and the FVCC Education Association.

ERIC Educational Resources Information Center

Flathead Valley Community Coll., Kalispell, MT.

This collective bargaining agreement between the Flathead Valley Community College (FVCC) Board of Trustees and the FVCC Education Association establishes management rights, rights of members, and terms of employment for the period July 1, 1989 through June 30, 1991. The 22 articles in the agreement include the following: (1) preamble; (2)…

Indigenous Knowledge and Geoscience on the Flathead Indian Reservation, Northwest Montana: Implications for Place-Based and Culturally Congruent Education

ERIC Educational Resources Information Center

Johnson, Adam N.; Sievert, Regina; Durglo, Michael, Sr.; Finley, Vernon; Adams, Louis; Hofmann, Michael H.

2014-01-01

We investigated connections between the natural and the cultural history of the Flathead Indian Reservation through the integration of geoscience, traditional tribal knowledge, and oral narratives for the purpose of improving Earth Science education in the tribal community. The project served as an avenue for the incorporation of indigenous…

Hungry Horse Mitigation; Flathead Lake, 2001-2002 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, Barry

2003-06-09

The Confederated Salish and Kootenai Tribes (CSKT) and Montana Fish Wildlife and Parks (MFWP) wrote ''Fisheries Mitigation Plan for Losses Attributable to the Construction and Operation of Hungry Horse Dam'' in March 1991 to define the fisheries losses, mitigation alternatives and recommendations to protect, mitigate and enhance resident fish and aquatic habitat affected by Hungry Horse Dam. On November 12, 1991, the Northwest Power Planning Council (NPPC) approved the mitigation plan with minor modifications, called for a detailed implementation plan, and amended measures 903(h)(1) through (7). A long-term mitigation plan was submitted in August 1992, was approved by the Councilmore » in 1993, and the first contract for this project was signed on November 11, 1993. The problem this project addresses is the loss of habitat, both in quality and quantity, in the interconnected Flathead Lake and River basin resulting from the construction and operation of Hungry Horse Dam. The purpose of the project is to both implement mitigation measures and monitor the biological responses to those measures including those implemented by Project Numbers 9101903 and 9101904. Goals and objectives of the 1994 Fish and Wildlife Program (Section 10.1) addressed by this project are the rebuilding to sustainable levels weak, but recoverable, native populations injured by the hydropower system. The project mitigates the blockage of spawning runs by Hungry Horse Dam by restoring and even creating spawning habitats within direct drainages to Flathead Lake. The project also addresses the altered habitat within Flathead Lake resulting from species shifts and consequent dominance of new species that restricts the potential success of mitigation measures. Specific goals of this project are to create and restore habitat and quantitatively monitor changes in fish populations to verify the efficacy of our mitigation measures. The project consists of three components: monitoring, restoration and research. Monitoring, for example, includes a spring gillnetting series conducted annually in Flathead Lake and builds on an existing data set initiated in 1981. Monitoring of the experimental kokanee reintroduction was a primary activity of this project between 1992 and 1997. Lake trout, whose high densities have precluded successful mitigation of losses of other species in Flathead Lake, have been monitored since 1996 to measure several biological parameters. Results of this work have utility in determining the population status of this key predator in Flathead Lake. The project has also defined the baseline condition of the Flathead Lake fishery in 1992-1993 and has conducted annual lakewide surveys since 1998. The restoration component of the project has addressed several stream channel, riparian, and fish passage problems. The research component of the project began in FY 2000 and measured trophic linkages between M. relicta and other species to assist in predicting the results of potential mitigation strategies. Only Objective 1 in the workplan is funded entirely by Hungry Horse Mitigation funds. Additional funds are drawn from other sources to assist in completion of Objectives 2-6.« less

Flathead River Focus Watershed Coordinator, 2003-2004 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

DuCharme, Lynn

2004-06-01

The Bonneville Power Administration (BPA) has long been involved with funding of the Cooperative Habitat Protection and Improvement with Private Landowners program in accordance with the Northwest Power Planning Council's (NPPC) Fish & Wildlife Program (Section 7.7). Section 7.7B.1 requires the establishment of ''at least one model watershed coordinator selected by each representative state''. This project was initiated in 1997 with the purpose of fulfilling the NWPCC's watershed program within the Flathead River basin in western Montana. Currently, the Flathead watershed has been radically altered by hydropower and other land uses. With the construction of Hungry Horse, Bigfork and Kerrmore » dams, the Flathead River system has been divided into isolated populations. Bull trout have been listed as threatened by the US Fish and Wildlife Service and westslope cutthroat trout have been petitioned for listing. Many streams in the drainage have been destabilized during recent decades. Past legal and illegal species introductions are also causing problems. This project fosters in-kind, out-of-place mitigation to offset the impacts of hydroelectric power to 72 miles of the South Fork of the Flathead River and its tributaries upstream of Hungry Horse Dam. Key subbasins within the Flathead drainage, which are critical to native species restoration, are experiencing rapid changes in land ownership and management direction. Subdivision and residential development of agricultural and timber lands adjacent to waterways in the drainage pose one of the greatest threats to weak but recoverable stocks of trout species. Plum Creek Timber Company, a major landholder in the Flathead drainage is currently divesting itself of large tracks of its lakeshore and streamside holdings. Growth of small tract development throughout the area and its tributaries is occurring at a record rate. Immediate to short-term action is required to protect stream corridors through many of these areas if cost-effective recovery efforts are to be implemented. In order to adequately address the issues, other segments of society and other (non-BPA) funding sources must be incorporated into the solution. As stated in the 1994 Fish and Wildlife Program (section 7.7), ''Comprehensive watershed management should enhance and expedite implementation of actions by clearly identifying gaps in programs and knowledge, by striving over time to resolve conflicts, and by keying on activities that address priorities''. A watershed coordinator helps to initiate and facilitate efforts for addressing the issues mentioned above and pulling together a plan for mitigation. Local support is essential before local governments and individual citizens are going to allow government initiatives to be implemented.« less

Flathead River Focus Watershed Coordinator, 2002 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

DuCharme, Lynn

2003-04-01

The Bonneville Power Administration (BPA) has long been involved with funding of the Cooperative Habitat Protection and Improvement with Private Landowners program in accordance with the Northwest Power Planning Council's (NPPC) Fish & Wildlife Program (Section 7.7). Section 7.7B.1 requires the establishment of ''at least one model watershed coordinator selected by each representative state''. This project was initiated in 1997 with the purpose of fulfilling the NPPC's watershed program within the Flathead River basin in western Montana. Currently, the Flathead watershed has been radically altered by hydropower and other land uses. With the construction of Hungry Horse, Bigfork and Kerrmore » dams, the Flathead River system has been divided into isolated populations. Bull trout have been listed as threatened by the US Fish and Wildlife Service and westslope cutthroat trout have been petitioned for listing. Many streams in the drainage have been destabilized during recent decades. Past legal and illegal species introductions are also causing problems. This project fosters in-kind, out-of-place mitigation to offset the impacts of hydroelectric power to 72 miles of the South Fork of the Flathead River and its tributaries upstream of Hungry Horse Dam. Key subbasins within the Flathead drainage, which are critical to native species restoration, are experiencing rapid changes in land ownership and management direction. Subdivision and residential development of agricultural and timber lands adjacent to waterways in the drainage pose one of the greatest threats to weak but recoverable stocks of trout species. Plum Creek Timber Company, a major landholder in the Flathead drainage is currently divesting itself of large tracks of its lakeshore and streamside holdings. Growth of small tract development throughout the area and its tributaries is occurring at a record rate. Immediate to short-term action is required to protect stream corridors through many of these areas if cost-effective recovery efforts are to be implemented. In order to adequately address the issues, other segments of society and other (non-BPA) funding sources must be incorporated into the solution. As stated in the 1994 Fish and Wildlife Program (section 7.7), ''Comprehensive watershed management should enhance and expedite implementation of actions by clearly identifying gaps in programs and knowledge, by striving over time to resolve conflicts, and by keying on activities that address priorities''. A watershed coordinator helps to initiate and facilitate efforts for addressing the issues mentioned above and pulling together a plan for mitigation. Local support is essential before local governments and individual citizens are going to allow government initiatives to be implemented.« less

Flathead River Focus Watershed Coordinator, 2004-2005 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

DuCharme, Lynn

2006-06-26

The Bonneville Power Administration (BPA) has long been involved with funding of the Cooperative Habitat Protection and Improvement with Private Landowners program in accordance with the Northwest Power Planning Council's (NPPC) Fish & Wildlife Program (Section 7.7). Section 7.7B.1 requires the establishment of ''at least one model watershed coordinator selected by each representative state''. This project was initiated in 1997 with the purpose of fulfilling the NWPCC's watershed program within the Flathead River basin in western Montana. Currently, the Flathead watershed has been radically altered by hydropower and other land uses. With the construction of Hungry Horse, Bigfork and Kerrmore » dams, the Flathead River system has been divided into isolated populations. Bull trout have been listed as threatened by the US Fish and Wildlife Service and westslope cutthroat trout have been petitioned for listing. Many streams in the drainage have been destabilized during recent decades. Past legal and illegal species introductions are also causing problems. This project fosters in-kind, out-of-place mitigation to offset the impacts of hydroelectric power to 72 miles of the South Fork of the Flathead River and its tributaries upstream of Hungry Horse Dam. Key subbasins within the Flathead drainage, which are critical to native species restoration, are experiencing rapid changes in land ownership and management direction. Subdivision and residential development of agricultural and timber lands adjacent to waterways in the drainage pose one of the greatest threats to weak but recoverable stocks of trout species. Plum Creek Timber Company, a major landholder in the Flathead drainage is currently divesting itself of large tracks of its lakeshore and streamside holdings. Growth of small tract development throughout the area and its tributaries is occurring at a record rate. Immediate to short-term action is required to protect stream corridors through many of these areas if cost-effective recovery efforts are to be implemented. In order to adequately address the issues, other segments of society and other (non-BPA) funding sources must be incorporated into the solution. As stated in the 1994 Fish and Wildlife Program (section 7.7), ''Comprehensive watershed management should enhance and expedite implementation of actions by clearly identifying gaps in programs and knowledge, by striving over time to resolve conflicts, and by keying on activities that address priorities''. A watershed coordinator helps to initiate and facilitate efforts for addressing the issues mentioned above and pulling together a plan for mitigation. Local support is essential before local governments and individual citizens are going to allow government initiatives to be implemented.« less

Flathead River Focus Watershed Coordinator, 2005-2006 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

DuCharme, Lynn

2006-05-01

The Bonneville Power Administration (BPA) has long been involved with funding of the Cooperative Habitat Protection and Improvement with Private Landowners program in accordance with the Northwest Power Planning Council's (NPPC) Fish & Wildlife Program (Section 7.7). Section 7.7B.1 requires the establishment of ''at least one model watershed coordinator selected by each representative state''. This project was initiated in 1997 with the purpose of fulfilling the NWPCC's watershed program within the Flathead River basin in western Montana. Currently, the Flathead watershed has been radically altered by hydropower and other land uses. With the construction of Hungry Horse, Bigfork and Kerrmore » dams, the Flathead River system has been divided into isolated populations. Bull trout have been listed as threatened by the US Fish and Wildlife Service and westslope cutthroat trout have been petitioned for listing. Many streams in the drainage have been destabilized during recent decades. Past legal and illegal species introductions are also causing problems. This project fosters in-kind, out-of-place mitigation to offset the impacts of hydroelectric power to 72 miles of the South Fork of the Flathead River and its tributaries upstream of Hungry Horse Dam. Key subbasins within the Flathead drainage, which are critical to native species restoration, are experiencing rapid changes in land ownership and management direction. Subdivision and residential development of agricultural and timber lands adjacent to waterways in the drainage pose one of the greatest threats to weak but recoverable stocks of trout species. Plum Creek Timber Company, a major landholder in the Flathead drainage is currently divesting itself of large tracks of its lakeshore and streamside holdings. Growth of small tract development throughout the area and its tributaries is occurring at a record rate. Immediate to short-term action is required to protect stream corridors through many of these areas if cost-effective recovery efforts are to be implemented. In order to adequately address the issues, other segments of society and other (non-BPA) funding sources must be incorporated into the solution. As stated in the 1994 Fish and Wildlife Program (section 7.7), ''Comprehensive watershed management should enhance and expedite implementation of actions by clearly identifying gaps in programs and knowledge, by striving over time to resolve conflicts, and by keying on activities that address priorities''. A watershed coordinator helps to initiate and facilitate efforts for addressing the issues mentioned above and pulling together a plan for mitigation. Local support is essential before local governments and individual citizens are going to allow government initiatives to be implemented.« less

Seismic reflection study of Flathead Lake, Montana

USGS Publications Warehouse

Wold, Richard J.

1982-01-01

A seismic reflection survey of Flathead Lake, Montana, was carried out in 1970 to study the geologic structure underlying the lake. Approximately 200 km of track lines were surveyed resulting in about 140 km of useable data (Fig. 1). A one cu. in. air gun was used as the energy source. Navigation was by a series of theodolite sitings of the boat from pairs of shore-based control points. 

Taxonomic status of Ligophorus mugilinus (Hargis, 1955) (Monogenea: Ancyrocephalidae), with a description of a new species of Ligophorus from Mugil cephalus (Teleostei: Mugilidae) in the Mediterranean Basin.

PubMed

Sarabeev, Volodimir Leonidovich; Balbuena, Juan Antonio; Euzet, Louis

2005-12-01

Ligophorus mugilinus was originally described on the flathead mullet Mugil cephalus from the Gulf of Mexico. The species was later recorded in the Mediterranean Sea on the flathead mullet and in the Caribbean Sea on the white mullet Mugil curema. After examination of the type material and additional specimens of Ligophorus from the northwest Atlantic coast, the Caribbean Sea, and the Mediterranean and Black Sea, we observed morphological differences concerning haptoral and male copulatory structures between L. mugilinus from the northwest Atlantic and the forms from the Mediterranean and Black Seas. Accordingly, the latter specimens are described as a new species, Ligophorus mediterraneus n. sp. A redescription of L. mugilinus, including new morphometric data, is also given. The morphometric analysis of the Caribbean specimens suggested that their ascription to L. mugilinus is uncertain, but additional material is needed to clarify their specific identity. The results of this study, together with previous zoogeographical evidence, indicate that flathead mullets from different seas harbor different species complexes of Ligophorus. Given the coastal habits of the host, it is suggested that open oceans could act as geographical barriers favoring speciation within disjointed flathead mullet populations.

Hungry Horse Mitigation; Flathead Lake, 2003-2004 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, Barry; Evarts, Les

2005-06-01

The Confederated Salish and Kootenai Tribes (CSKT) and Montana Fish Wildlife and Parks (MFWP) wrote the ''Fisheries Mitigation Plan for Losses Attributable to the Construction and Operation of Hungry Horse Dam'' in March 1991 to define the fisheries losses, mitigation alternatives and recommendations to protect, mitigate and enhance resident fish and aquatic habitat affected by Hungry Horse Dam. On November 12, 1991, the Northwest Power Planning Council (NPPC) approved the mitigation plan with minor modifications, called for a detailed implementation plan, and amended measures 903(h)(1) through (7). A long-term mitigation plan was submitted in August 1992, was approved by themore » Council in 1993, and the first contract for this project was signed on November 11, 1993. The problem this project addresses is the loss of habitat, both in quality and quantity, in the Flathead Lake and River basin resulting from the construction and operation of Hungry Horse Dam. The purpose of the project is to both implement mitigation measures and monitor the biological responses to those measures including those implemented by Project Numbers 9101903 and 9101904. Goals and objectives of the 1994 Fish and Wildlife Program (Section 10.1) addressed by this project are the rebuilding to sustainable levels weak, but recoverable, native populations injured by the hydropower system. The project mitigates the blockage of spawning runs by Hungry Horse Dam by restoring and even creating spawning habitats within direct drainages to Flathead Lake. The project also addresses the altered habitat within Flathead Lake resulting from species shifts and consequent dominance of new species that restricts the potential success of mitigation measures. Specific goals of this project are to create and restore habitat and quantitatively monitor changes in fish populations to verify the efficacy of our mitigation measures. The project consists of three components: monitoring, restoration and research. Monitoring, for example, includes a spring gillnetting series conducted annually in Flathead Lake and builds on an existing data set initiated in 1981. Monitoring of the experimental kokanee reintroduction was a primary activity of this project between 1992 and 1997. Lake trout, whose high densities have precluded successful mitigation of losses of other species in Flathead Lake, have been monitored since 1996 to measure several biological parameters. Results of this work have utility in determining the population status of this key predator in Flathead Lake. The project has also defined the baseline condition of the Flathead Lake fishery in 1992-1993 and has conducted annual lakewide surveys since 1998. The restoration component of the project has addressed several stream channel, riparian, and fish passage problems, and suppression of non-native fish. The research component of the project began in FY 2000 and measured trophic linkages between M. relicta and other species to assist in predicting the results of our efforts to suppress lake trout. Only Objective 1 in the workplan is funded entirely by Hungry Horse Mitigation funds. Additional funds are drawn from other sources to assist in completion of Objectives 2-8.« less

Hungry Horse Mitigation : Flathead Lake : Annual Progress Report 2007.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, Barry; Evarts, Les

2008-12-22

The Confederated Salish and Kootenai Tribes (CSKT) and Montana Fish Wildlife and Parks (MFWP) wrote the 'Fisheries Mitigation Plan for Losses Attributable to the Construction and Operation of Hungry Horse Dam' in March 1991 to define the fisheries losses, mitigation alternatives and recommendations to protect, mitigate and enhance resident fish and aquatic habitat affected by Hungry Horse Dam. On November 12, 1991, the Northwest Power Planning Council (NPPC) approved the mitigation plan with minor modifications, called for a detailed implementation plan, and amended measures 903(h)(1) through (7). A long-term mitigation plan was submitted in August 1992, was approved by themore » Council in 1993, and the first contract for this project was signed on November 11, 1993. The problem this project addresses is the loss of habitat, both in quality and quantity, in the Flathead Lake and River basin resulting from the construction and operation of Hungry Horse Dam. The purpose of the project is to both implement mitigation measures and monitor the biological responses to those measures including those implemented by Project Numbers 9101903 and 9101904. Goals and objectives of the 1994 Fish and Wildlife Program (Section 10.1) addressed by this project are the rebuilding to sustainable levels weak, but recoverable, native populations injured by the hydropower system. The project mitigates the blockage of spawning runs by Hungry Horse Dam by restoring and even creating spawning habitats within direct drainages to Flathead Lake. The project also addresses the altered habitat within Flathead Lake resulting from species shifts and consequent dominance of new species that restricts the potential success of mitigation measures. Specific goals of this project are to create and restore habitat and quantitatively monitor changes in fish populations to verify the efficacy of our mitigation measures. The project consists of three components: monitoring, restoration and research. Monitoring, for example, includes a spring gillnetting series conducted annually in Flathead Lake and builds on an existing data set initiated in 1981. Monitoring of the experimental kokanee reintroduction was a primary activity of this project between 1992 and 1997. Lake trout, whose high densities have precluded successful mitigation of losses of other species in Flathead Lake, have been monitored since 1996 to measure several biological parameters. Results of this work have utility in determining the population status of this key predator in Flathead Lake. The project has also defined the baseline condition of the Flathead Lake fishery in 1992-1993 and has conducted annual lakewide surveys since 1998. The restoration component of the project has addressed several stream channel, riparian, and fish passage problems, and suppression of non-native fish. The research component of the project began in FY 2000 and measured trophic linkages between M. relicta and other species to assist in predicting the results of our efforts to suppress lake trout. Only Work Element A in the Statement of Work is funded entirely by Hungry Horse Mitigation funds. Additional funds are drawn from other sources to assist in completion of all remaining Work Elements.« less

Hungry Horse Mitigation; Flathead Lake, 2004-2005 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, Barry; Evarts, Les

2006-06-01

The Confederated Salish and Kootenai Tribes (CSKT) and Montana Fish Wildlife and Parks (MFWP) wrote the ''Fisheries Mitigation Plan for Losses Attributable to the Construction and Operation of Hungry Horse Dam'' in March 1991 to define the fisheries losses, mitigation alternatives and recommendations to protect, mitigate and enhance resident fish and aquatic habitat affected by Hungry Horse Dam. On November 12, 1991, the Northwest Power Planning Council (NPPC) approved the mitigation plan with minor modifications, called for a detailed implementation plan, and amended measures 903(h)(1) through (7). A long-term mitigation plan was submitted in August 1992, was approved by themore » Council in 1993, and the first contract for this project was signed on November 11, 1993. The problem this project addresses is the loss of habitat, both in quality and quantity, in the Flathead Lake and River basin resulting from the construction and operation of Hungry Horse Dam. The purpose of the project is to both implement mitigation measures and monitor the biological responses to those measures including those implemented by Project Numbers 9101903 and 9101904. Goals and objectives of the 1994 Fish and Wildlife Program (Section 10.1) addressed by this project are the rebuilding to sustainable levels weak, but recoverable, native populations injured by the hydropower system. The project mitigates the blockage of spawning runs by Hungry Horse Dam by restoring and even creating spawning habitats within direct drainages to Flathead Lake. The project also addresses the altered habitat within Flathead Lake resulting from species shifts and consequent dominance of new species that restricts the potential success of mitigation measures. Specific goals of this project are to create and restore habitat and quantitatively monitor changes in fish populations to verify the efficacy of our mitigation measures. The project consists of three components: monitoring, restoration and research. Monitoring, for example, includes a spring gillnetting series conducted annually in Flathead Lake and builds on an existing data set initiated in 1981. Monitoring of the experimental kokanee reintroduction was a primary activity of this project between 1992 and 1997. Lake trout, whose high densities have precluded successful mitigation of losses of other species in Flathead Lake, have been monitored since 1996 to measure several biological parameters. Results of this work have utility in determining the population status of this key predator in Flathead Lake. The project has also defined the baseline condition of the Flathead Lake fishery in 1992-1993 and has conducted annual lakewide surveys since 1998. The restoration component of the project has addressed several stream channel, riparian, and fish passage problems, and suppression of non-native fish. The research component of the project began in FY 2000 and measured trophic linkages between M. relicta and other species to assist in predicting the results of our efforts to suppress lake trout. Only Work Element A in the Statement of Work is funded entirely by Hungry Horse Mitigation funds. Additional funds are drawn from other sources to assist in completion of all remaining Work Elements.« less

Hungry Horse Mitigation : Flathead Lake : Annual Progress Report 2008.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, Barry; Evarts, Les

2009-08-06

The Confederated Salish and Kootenai Tribes (CSKT) and Montana Fish Wildlife and Parks (MFWP) wrote the 'Fisheries Mitigation Plan for Losses Attributable to the Construction and Operation of Hungry Horse Dam' in March 1991 to define the fisheries losses, mitigation alternatives and recommendations to protect, mitigate and enhance resident fish and aquatic habitat affected by Hungry Horse Dam. On November 12, 1991, the Northwest Power Planning Council (NPPC) approved the mitigation plan with minor modifications, called for a detailed implementation plan, and amended measures 903(h)(1) through (7). A long-term mitigation plan was submitted in August 1992, was approved by themore » Council in 1993, and the first contract for this project was signed on November 11, 1993. The problem this project addresses is the loss of habitat, both in quality and quantity, in the Flathead Lake and River basin resulting from the construction and operation of Hungry Horse Dam. The purpose of the project is to both implement mitigation measures and monitor the biological responses to those measures including those implemented by Project Numbers 9101903 and 9101904. Goals and objectives of the 1994 Fish and Wildlife Program (Section 10.1) addressed by this project are the rebuilding to sustainable levels weak, but recoverable, native populations injured by the hydropower system. The project mitigates the blockage of spawning runs by Hungry Horse Dam by restoring and even creating spawning habitats within direct drainages to Flathead Lake. The project also addresses the altered habitat within Flathead Lake resulting from species shifts and consequent dominance of new species that restricts the potential success of mitigation measures. Specific goals of this project are to create and restore habitat and quantitatively monitor changes in fish populations to verify the efficacy of our mitigation measures. The project consists of three components: monitoring, restoration and research. Monitoring, for example, includes a spring gillnetting series conducted annually in Flathead Lake and builds on an existing data set initiated in 1981. Monitoring of the experimental kokanee reintroduction was a primary activity of this project between 1992 and 1997. Lake trout, whose high densities have precluded successful mitigation of losses of other species in Flathead Lake, have been monitored since 1996 to measure several biological parameters. Results of this work have utility in determining the population status of this key predator in Flathead Lake. The project has also defined the baseline condition of the Flathead Lake fishery in 1992-1993 and has conducted annual lakewide surveys since 1998. The restoration component of the project has addressed several stream channel, riparian, and fish passage problems, and suppression of non-native fish. The research component of the project began in FY 2000 and measured trophic linkages between M. relicta and other species to assist in predicting the results of our efforts to suppress lake trout. Only Work Element A in the Statement of Work is funded entirely by Hungry Horse Mitigation funds. Additional funds are drawn from other sources to assist in completion of all remaining Work Elements.« less

Next generation sequencing yields the complete mitochondrial genome of the flathead mullet, Mugil cephalus cryptic species NWP2 (Teleostei: Mugilidae).

PubMed

Shen, Kang-Ning; Yen, Ta-Chi; Chen, Ching-Hung; Li, Huei-Ying; Chen, Pei-Lung; Hsiao, Chung-Der

2016-05-01

In this study, the complete mitogenome sequence of Northwestern Pacific 2 (NWP2) cryptic species of flathead mullet, Mugil cephalus (Teleostei: Mugilidae) has been amplified by long-range PCR and sequenced by next-generation sequencing method. The assembled mitogenome, consisting of 16,686 bp, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes and a non-coding control region of D-loop. D-loop was 909 bp length and was located between tRNA-Pro and tRNA-Phe. The overall base composition of NWP2 M. cephalus was 28.4% for A, 29.8% for C, 26.5% for T and 15.3% for G. The complete mitogenome may provide essential and important DNA molecular data for further phylogenetic and evolutionary analysis for flathead mullet species complex.

Hematologic, cytochemical, ultrastructural, and molecular findings of Hepatozoon-infected flat-headed cats (Prionailurus planiceps).

PubMed

Salakij, Chaleow; Salakij, Jarernsak; Narkkong, Nual-Anong; Sirinarumitr, Theerapol; Pattanarangsan, Rattapan

2008-03-01

The flat-headed cat (Prionailurus planiceps) is a small wild cat of Southeast Asia and is considered extremely endangered. Little is known about the hematologic values, blood cell morphology, or hemoparasites of this species in relation to other Felidae. The objective of this study was to report basic hematologic values and describe the light microscopic, cytochemical, and ultrastructural characteristics of blood cells in 2 wild-caught flat-headed cats. In addition, molecular analysis was done of a Hepatozoon organism found in the neutrophils of both cats. Blood samples were collected into EDTA from the cephalic vein. A CBC, manual differential count, manual reticulocyte count, cytochemical stains (Sudan black B [SBB], alpha-naphthyl acetate esterase [ANAE], and beta-glucuronidase), and scanning and transmission electron microscopy were done using standard methods. HCT was slightly lower and reticulocyte counts and red cell distribution width were higher than the expected values for other species of cats. Hepatozoon organisms were found in the cytoplasm of neutrophils in both cats, but the number of infected neutrophils was very low (1%-2%). Neutrophils stained strongly positive for SBB, but were negative for ANAE and beta-glucuronidase. Hepatozoon-infected neutrophils were negative for SBB, but focally positive for ANAE and beta-glucuronidase. By transmission electron microscopy, gamonts of Hepatozoon sp were observed in neutrophils, and rarely free in plasma. Infected neutrophils had fewer specific granules and more mitochondria compared with noninfected neutrophils. PCR products of partial 18S rRNA revealed that the isolate of Hepatozoon in the flat-headed cats was closely related to that of the frog Hepatozoon sp. These results add to our understanding of hematologic values and blood cell morphology in Hepatozoon-infected flat-headed cats as well as the molecular analysis of the Hepatozoon organism, and may be useful for the health management and evaluation of hemoparasitic disease in this species.

Impacts of Water Levels on Breeding Canada Geese and Methods for Mitigation and Management in the Southern Flathead Valley, Montana, 1983-1987 Final Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mackey, Dennis L.; Gregory, Shari K.; Matthews, William C. Jr.

Kerr Hydroelectric Dam is located at the south end of Flathead Lake, controls water levels on the lake and the Flathead River below the dam, and is currently operated as a load control facility. Current operation of Kerr Dam creates the greatest yearly water level fluctuations on both the lake and river during the Canada goose (Branta canadensis moffitti) brood and nesting period. Data collected from 1980-1982 indicated that goose nest numbers on the river were lower than during the 1950's, and that brood habitat on the lake may be limiting the goose population there. Our study was conducted frommore » 1983-1987 to determine the effects of Kerr Dam operation on Canada goose populations and habitat on the south half of Flathead Lake and the Flathead River, and to formulate management and mitigation recommendations. Nesting geese on the river appeared to be negatively affected by a lack of nest sites free from predators, and responded to available artificial nest structures with an increase in nest numbers and nesting success. Under current dam operation, river channel depths and widths do not discourage access to nesting islands by mammalian predators during some years and high predation on ground nests occurs. Intensively used brood areas on the lake and river were identified and described. Brood habitat on the lake was lower in quality and quantity than on the river due to dam operations. Gosling mortality on the lake was high, almost 2 times higher than on the river. Lake broods expended more energy obtaining food than river broods. Losses of brood habitat in the form of wet meadow marshes were documented and mitigation options developed. Management/mitigation alternatives and monitoring methods for nesting and brooding geese were identified.« less

Lake trout (Salvelinus namaycush) suppression for bull trout (Salvelinus confluentus) recovery in Flathead Lake, Montana, North America

USGS Publications Warehouse

Hansen, Michael J.; Hansen, Barry S; Beauchamp, David A.

2016-01-01

Non-native lake trout Salvelinus namaycush displaced native bull trout Salvelinus confluentus in Flathead Lake, Montana, USA, after 1984, when Mysis diluviana became abundant following its introduction in upstream lakes in 1968–1976. We developed a simulation model to determine the fishing mortality rate on lake trout that would enable bull trout recovery. Model simulations indicated that suppression of adult lake trout by 75% from current abundance would reduce predation on bull trout by 90%. Current removals of lake trout through incentivized fishing contests has not been sufficient to suppress lake trout abundance estimated by mark-recapture or indexed by stratified-random gill netting. In contrast, size structure, body condition, mortality, and maturity are changing consistent with a density-dependent reduction in lake trout abundance. Population modeling indicated total fishing effort would need to increase 3-fold to reduce adult lake trout population density by 75%. We conclude that increased fishing effort would suppress lake trout population density and predation on juvenile bull trout, and thereby enable higher abundance of adult bull trout in Flathead Lake and its tributaries.

Winter diel habitat use and movement by subadult bull trout in the upper Flathead River, Montana

USGS Publications Warehouse

Muhlfeld, Clint C.; Glutting, Steve; Hunt, Rick; Daniels, Durae; Marotz, Brian

2003-01-01

We evaluated the diel habitat use and movement of subadult bull trout Salvelinus confluentus by use of radiotelemetry during winter in the upper Flathead River, Montana. Of the 13 monitored bull trout, 12 (92%) made at least one diel movement to other habitat locations during their respective day–night tracking surveys and moved an average of 73% of the time. The median distance moved from day to night locations by the mobile fish was 86 m (range, 27–594 m). Diel shifts in habitat use by nine of the tagged fish were related to light intensity; nocturnal emergence generally commenced immediately after the onset of night, and daytime concealment occurred at daybreak. When diel shifts in microhabitat use occurred, subadult bull trout moved from deep, midchannel areas during the day to shallow, low-velocity areas along the channel margins without overhead cover at night. Resource managers who wish to protect the overwintering habitat features preferred by subadult bull trout in the upper Flathead River should use natural flow management strategies that maximize and stabilize channel margin habitats at night.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fraley, John J.; Marotz, Brian L.; DosSantos, Joseph M.

In this document we present fisheries losses, mitigation alternatives, and recommendations to protect, mitigate, and enhance resident fish and aquatic habitat affected by the construction and operation of Hungry Horse Dam. This plan addresses six separate program measures in the 1987 Columbia Basin Fish and Wildlife Program. We designed the plan to be closely coordinated in terms of dam operations, funding, and activities with the Kerr Mitigation Plan presently before the Federal Energy Regulatory Commission. This document represents a mitigation plan for consideration by the Northwest Power Planning Council process; it is not an implementation plan. Flathead Lake is onemore » of the cleanest lakes of its size in the world. The exceptional water quality and unique native fisheries make the Flathead Lake/River system extremely valuable to the economy and quality of life in the basin. The recreational fishery in Flathead Lake has an estimated value of nearly eight million dollars annually. This mitigation process represents our best opportunity to reduce the impacts of hydropower in this valuable aquatic system and increase angling opportunity. We based loss estimates and mitigation alternatives on an extensive data base, agency reports, nationally and internationally peer-reviewed scientific articles, and an innovative biological model for Hungry Horse Reservoir and the Flathead River. We conducted an extensive, 14-month scoping and consultation process with agency representatives, representatives of citizen groups, and the general public. This consultation process helped identify issues, areas of agreement, areas of conflict, and advantages and disadvantages of mitigation alternatives. The results of the scoping and consultation process helped shape our mitigation plan. Our recommended plan is based firmly on principles of adaptive management and recognition of biological uncertainty. After we receive direction from the NPPC, we will add more detailed hypotheses and other features necessary for a long-term implementation plan.« less

Effect of the Operation of Kerr and Hungry Horse Dams on the Reproductive Success of Kokanee in the Flathead System; Technical Addendum to the Final Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beattie, Will; Tohtz, Joel

1990-03-01

This addendum to the Final Report presents results of research on the zooplankton and fish communities of Flathead Lade. The intent of the Study has been to identify the impacts of hydroelectric operations at Kerr and Hungry Horse Dam on the reproductive success of kokanee an to propose mitigation for these impacts. Recent changes in the trophic ecology of the lake, have reduced the survival of kokanee. In the last three year the Study has been redirected to identify, if possible, the biological mechanisms which now limit kokanee survival, and to test methods of enhancing the kokanee fishery by artificialmore » supplementation. These studies were necessary to the formulation of mitigation plans. The possibility of successfully rehabilitating the kokanee population, is the doubt because of change in the trophic ecology of the system. This report first presents the results of studies of the population dynamics of crustacean zooplankton, upon which planktivorous fish depend. A modest effort was directed to measuring the spawning escapement of kokanee in 1988. Because of its relevance to the study, we also report assessments of 1989 kokanee spawning escapement. Hydroacoustic assessment of the abundance of all fish species in Flathead Lake was conducted in November, 1988. Summary of the continued efforts to document the growth rates and food habits of kokanee and lake whitefish are included in this report. Revised kokanee spawning and harvest estimates, and management implications of the altered ecology of Flathead Lake comprise the final sections of this addendum. 83 refs., 20 figs., 25 tabs.« less

An evaluation of agreement between pectoral spines and otoliths for estimating ages of catfishes

USGS Publications Warehouse

Olive, J.A.; Schramm, Harold; Gerard, Patrick D.; Irwin, E.

2011-01-01

Otoliths have been shown to provide more accurate ages than pectoral spine sections for several catfish populations; but sampling otoliths requires euthanizing the specimen, whereas spines can be sampled non-lethally. To evaluate whether, and under what conditions, spines provide the same or similar age estimates as otoliths, we examined data sets of individual fish aged from pectoral spines and otoliths for six blue catfish Ictalurus furcatus populations (n=420), 14 channel catfish Ictalurus punctatus populations (n=997), and 10 flathead catfish Pylodictus olivaris populations (n=947) from lotic and lentic waters throughout the central and eastern U.S. Logistic regression determined that agreement between ages estimated from otoliths and spines was consistently related to age, but inconsistently related to growth rate. When modeled at mean growth rate, we found at least 80% probability of no difference in spine- and otolith-assigned ages up to ages 4 and 5 for blue and channel catfish, respectively. For flathead catfish, an 80% probability of agreement between spine- and otolith-assigned ages did not occur at any age due to high incidence of differences in assigned ages even for age-1 fish. Logistic regression models predicted at least 80% probability that spine and otolith ages differed by ≤1 year up to ages 13, 16, and 9 for blue, channel, and flathead catfish, respectively. Age-bias assessment found mean spine-assigned age differed by less than 1 year from otolith-assigned age up to ages 19, 9, and 17 for blue catfish, channel catfish, and flathead catfish, respectively. These results can be used to help guide decisions about which structure is most appropriate for estimating catfish ages for particular populations and management objectives.

Species- and tissue-specific mercury bioaccumulation in five fish species from Laizhou Bay in the Bohai Sea of China

NASA Astrophysics Data System (ADS)

Liu, Jinhu; Cao, Liang; Huang, Wei; Dou, Shuozeng

2013-05-01

Mercury (Hg) concentrations in the tissues (muscle, stomach, liver, gills, skin, and gonads) of five fish species (mullet Liza ha em atocheil us, flathead fish Platycephalus indicus, sea bass Lateolabrax japonic u s, mackerel Scomberomorus niphonius and silver pomfret Pampus argenteus) collected from Laizhou Bay in the Bohai Sea of China were investigated. The results indicate that Hg bioaccumulation in the five fish was tissue-specific, with the highest levels in the muscle and liver, followed by the stomach and gonads. The lowest levels were found in the gills and skin. Fish at higher trophic levels (flathead fish and sea bass) exhibited higher Hg concentrations than consumers at lower trophic levels. Mercury bioaccumulation tended to be positively correlated with fish length in mullet, silver pomfret, mackerel, and flathead fish, but was negatively correlated with fish length in sea bass. The Hg concentrations in the muscles of all fish species in Laizhou Bay were within the permissible limits of food safety set by national and international criteria. However, the suggesting maximum consumption of sea bass is 263 g per week for human health.

Watershed scale response to climate change--South Fork Flathead River Basin, Montana

USGS Publications Warehouse

Chase, Katherine J.; Hay, Lauren E.; Markstrom, Steven L.

2012-01-01

Fourteen basins for which the Precipitation Runoff Modeling System has been calibrated and evaluated were selected as study sites. Precipitation Runoff Modeling System is a deterministic, distributed parameter watershed model developed to evaluate the effects of various combinations of precipitation, temperature, and land use on streamflow and general basin hydrology. Output from five General Circulation Model simulations and four emission scenarios were used to develop an ensemble of climate-change scenarios for each basin. These ensembles were simulated with the corresponding Precipitation Runoff Modeling System model. This fact sheet summarizes the hydrologic effect and sensitivity of the Precipitation Runoff Modeling System simulations to climate change for the South Fork Flathead River Basin, Montana.

Preliminary bedrock geologic map of part of the northern disturbed belt, Lewis and Clark, Teton, Pondera, Glacier, Flathead, and Powell Counties, Montana

USGS Publications Warehouse

Mudge, Melville R.; Earhart, Robert L.; Rice, Dudley D.; Heisey, E.L.

1977-01-01

The geologic map covers the Sawtooth and Lewis and Clark Ranges and part of the Flathead Range. It includes most of the disturbed belt in northwestern Moutana except the area east of the northern Rocky Mountains and the norhtern and southern parts of the belt. Most data are from an unpublished map of the Bob Marshall Wilderness and of the many proposed additions to the Wilderness. Strike and dip symbols are omitted from the map, and all contacts are shown in solid lines, alhough locally they are inferred beneath a Quaternary cover. Future studies will complete mapping of the northern disturbed belt in Montana.

Flathead Lake Angler Survey; Monitoring Activities for the Hungry Horse Fisheries Mitigation Plan, 1992-1993 Final Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Evarts, Les; Hansen, Barry; DosSantos, Joe

1994-02-01

A roving creel survey was conducted on Flathead Lake in northwestern Montana from May 17, 1992 to May 19, 1993. The primary objective of the survey was to quantify the baseline fishery and exploitation rates existing prior to Hungry Horse Dam mitigation efforts. Anglers were counted on 308 occasions, comprising 5,618 fishing boats, 515 shore anglers, and 2,191 ice anglers. The party interviews represented 4,410 anglers, made up of 2,613 boat anglers, 787 shore anglers, and 1,010 ice anglers. A total of 47,883 angler days (190,108 angler hours) of pressure and a harvest of 42,979 fish (including lake trout, lakemore » whitefish, yellow perch, bull trout, and westslope cutthroat trout) were estimated. Pressure was distributed between shore, boat, and ice anglers as 4%, 87%, and 9%, respectively. Seventynine percent of the total effort was directed at lake trout during the study period. Limited comparisons were made to previous creel surveys on Flathead Lake due to differences in methods and radical changes in the fishery. Potential sources of bias are explained in detail. Future creel surveys must employ methods consistent with this survey to obtain estimates that are statistically distinguishable.« less

Three new species of Ligophorus (Monogenea: Dactylogyridae) on the gills of Mugil cephalus (Teleostei: Mugilidae) from the Japan Sea.

PubMed

Rubtsova, Nataliya Y; Balbuena, Juan A; Sarabeev, Volodimir L

2007-08-01

Comparative morphology and multivariate morphometric analysis of monogeneans collected on flathead mullets Mugil cephalus from 2 Russian localities of the Japan Sea revealed the presence of 3 new species of Ligophorus, namely, L. domnichi n. sp., L. pacificus n. sp., and L. cheleus n. sp., which are described herein. So far, only 1 species of dactylogyrid monogenean identified as Ligophorus chabaudi was known on flathead mullets in this sea, but after comparison with the present material, we propose that this form actually represents L. domnichi n. sp. Results support previous zoogeographical evidence, suggesting that flathead mullets from different seas harbor different species complexes of Ligophorus. One interesting finding is that the 3 new species have a U-shaped ovary, whereas ovate ovaries have been reported in previous descriptions of species of the genus, e.g., L. vanbenedenii, L. parvicirrus, L. imitans, and L. chongmingensis. The U-shaped ovary was revealed only when the worms were observed in lateral view. The additional examination of L. vanbenedenii, L. parvicirrus, L. imitans, and L. pilengas specimens from our collections also revealed a U-shaped ovary in these forms as well. Further studies should establish whether or not this character is shared by all members of the genus.

Water resources of Hot Springs County, Wyoming

USGS Publications Warehouse

Plafcan, Maria; Ogle, Kathy Muller

1994-01-01

The wells and springs inventoried in Hot Springs County most commonly had been completed in or issued from the Quaternary alluvium, Quaternary terrace deposits, Fort Union and Mesaverde Formations, Cody Shale, and the Frontier and Chugwater Formations. The largest discharges measured were from the Quaternary terrace deposits (400 gallons per minute) and the Phosphoria Formation (1,000 gallons per minute). Discharges from all other geologic units varied, but most wells and springs yielded 50 gallons per minute or less.Water-quality samples collected from springs that issued from the Absaroka Volcanic Supergroup, the Bighorn Dolomite, and the Flathead Sandstone had the lowest dissolved-solids concentrations, which ranged from 58 to 265 milligrams per liter, and the least variable water types. Water from the volcanic rocks was a sodium bicarbonate type; whereas, water from the Flathead Sandstone was a calcium bicarbonate type. Water types for all the other aquifers varied from sampling site to sampling site; however, water samples from the Fort Union Formation and the Cody Shale were consistently of the sodium sulfate type. The effect of oil- and gas-development at Hamilton Dome on thermal spring discharges at Hot Springs State Park near Thermopolis was studied. The estimated drawdown from 1918, when the Hamilton Dome oil field was discovered, to 1988 was made using drill-stem data from previous studies. Drawdown at Big Spring in the Park was estimated to be less than 3 feet on the basis of recent oil- and water-production data, previous modeling studies, and the estimated water-level drawdown of 330 feet in wells at the Hamilton Dome oil field.Streams originating in the Plains region of the county, such as Middle Fork Owl Creek, are ephemeral or intermittent; whereas, streams originating in the mountains, such as Gooseberry Creek, are perennial. Average annual runoff across the county ranges from 0.26 inches at a representative streamflow-gaging station near Worland in the plains region to 5.4 inches in the Owl Creek Mountains and southeastern Absaroka Range.

Impacts of Water Levels on Breeding Canada Geese and the Methodology for Mitigation and Enhancement in the Flathead Drainage, 1984 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mackey, Dennis L.

1985-01-01

The lower Flathead System Canada Goose Study was initiated to determine population trends and the effects of water level fluctuations on nest and brood habitat on the southern half of Flathead Lake and the lower Flathead River as a result of the operations of Kerr Dam. This report presents data collected during the 1984 field season as part of an ongoing project. Geese used Pablo, Kicking Horse, Ninepipe Reservoirs heavily during late summer and fall. Use of the river by geese was high during the winter, when the reservoirs were frozen, and during the breeding period. Most breeding geese leftmore » the river after broods fledged. Thirteen percent of the artificial tree nest structures on the river were used by nesting geese. Goose nest initiation on the river peaked the last week in March through the first week in April, and hatching peaked the first week in May. Predation was the most significant cause of nest loss on the river, and nest loss by flooding was not observed. Avian predation was the single largest factor contributing to nest loss on the lake. Habitat use was studied in 4 brood areas on the river and 8 brood areas on the lake, and available habitat was assessed for 2 portions of both the lake and the river. Brood habitat use was significantly different from the available habitat in all areas studied. On the lower river, broods used wheat fields, gravel bars, and shrub habitats. On the upper river, coniferous forest and shrub habitats were preferred. On the West Bay of the lake, brood areas consisted primarily of lawns and tall herbaceous habitat, while on the South Bay, marshes dominated the brood areas studied. Water levels on the river and lake affect both accessibility of these areas to brooding geese, and the ecology of the habitats preferred by geese. 43 refs., 24 figs., 31 tabs.« less

Age, growth, and mortality of introduced flathead catfish in Atlantic rivers and a review of other populations

USGS Publications Warehouse

Kwak, T.J.; Pine, William E.; Waters, D.S.

2006-01-01

Knowledge of individual growth and mortality rates of an introduced fish population is required to determine the success and degree of establishment as well as to predict the fish's impact on native fauna. The age and growth of flathead catfish Pylodictis olivaris have been studied extensively in the species' native and introduced ranges, and estimates have varied widely. We quantified individual growth rates and age structure of three introduced flathead catfish populations in North Carolina's Atlantic slope rivers using sagittal otoliths, determined trends in growth rates over time, compared these estimates among rivers in native and introduced ranges, and determined total mortality rates for each population. Growth was significantly faster in the Northeast Cape Fear River (NECFR) than in the Lumber and Neuse rivers. Fish in the NECFR grew to a total length of 700 mm by age 7, whereas fish in the Neuse and Lumber river populations reached this length by 8 and 10 years, respectively. The growth rates of fish in all three rivers were consistently higher than those of native riverine populations, similar to those of native reservoir populations, and slower than those of other introduced riverine populations. In general, recent cohorts (1998-2001 year-classes) in these three rivers exhibited slower growth among all ages than did cohorts previous to the 1998 year-class. The annual total mortality rate was similar among the three rivers, ranging from 0.16 to 0.20. These mortality estimates are considerably lower than those from the Missouri and Mississippi rivers, suggesting relatively low fishing mortality for these introduced populations. Overall, flathead catfish populations in reservoirs grow faster than those in rivers, the growth rates of introduced populations exceed those of native populations, and eastern United States populations grow faster than those in western states. Such trends constitute critical information for understanding and managing local populations.

Geology of Glacier National Park and the Flathead Region, Northwestern Montana

USGS Publications Warehouse

Ross, Clyde P.

1959-01-01

This report summarizes available data on two adjacent and partly overlapping regions in northwestern Montana. The first of these is Glacier National Park plus small areas east and west of the park. The second is here called, for convenience, the Flathead region; it embraces the mountains from the southern tip of Glacier Park to latitude 48 deg north and between the Great Plains on the east and Flathead Valley on the west. The fieldwork under the direction of the writer was done in 1948, 1949, 1950, and 1951, with some work in 1952 and 1953. The two regions together include parts of the Swan, Flathead, Livingstone, and Lewis Ranges. They are drained largely by branches of the Flathead River. On the east and north, however, they are penetrated by tributaries of the Missouri River and in addition by streams that flow into Canada. Roads and highways reach the borders of the regions; but there are few roads in the regions and only two highways cross them. The principal economic value of the assemblage of mountains described in the present report is as a collecting ground for snow to furnish the water used in the surrounding lowlands and as a scenic and wildlife recreation area. A few metallic deposits and lignitic coal beds are known, but these have not proved to be important and cannot, as far as can now be judged, be expected to become so. No oil except minor seeps has yet been found, and most parts of the two regions covered do not appear geologically favorable to the presence of oil in commercial quantities. The high, Hungry Horse Dam on which construction was in progress during the fieldwork now floods part of the Flathead region and will greatly influence the future of that region. The rocks range in age from Precambrian to Recent. The thickest units belong to the Belt series of Precambrian age, and special attention was paid to them. As a result, it is clear that at least the upper part of the series shows marked lateral changes within short distances. This fact introduces complexities into stratigraphic correlation and should be remembered wherever the series is studied. The stromatolites, or fossil algae, in the Belt series, although still imperfectly understood, give clues with respect to problems of ecology and stratigraphy. The subdivisions of the Belt series within the areas covered by the present report are, in ascending order, Altyn limestone, Appekunny argillite, Grinnell argillite, Siyeh limestone, and Missoula group. Local subdivisions of the Missoula group are possible in certain areas, and all the units just named are expected to be subdivided when detailed studies are undertaken. In the Glacier National Park and Flathead regions together, it is probable that between 25,000 and 30,000 feet of beds belonging to the Belt series, possibly more, are present. These consist largely of quartzitic argillite, quartzite, and carbonate rocks, mostly dolomitic. Small gabbroic and diabasic intrusive bodies and, at one horizon, basaltic lava are associated with the Belt series. Above the Belt series is a thick sequence of Cambrian, Devonian, and Carboniferous strata, in which limestone is dominant, followed by strata of Jurassic and Cretaceous age, largely limestone and shale and partly of terrestrial origin. Slightly consolidated gravel, sand, and silt of Tertiary age are preserved in some valleys and as erosional remnants on the plains close to the mountain border. Pleistocene and Recent glacial and fluviatile deposits are plentiful in mountain valleys and on the plains east of the mountains. Sufficient crustal movements took place during the latter part of Belt time to produce tension cracks that permitted some intrusion and related extrusion to occur. Broad crustal warping probably took place at intervals during the Paleozoic era, but these successive movements left little record other than the absence of sedimentary rock units that might otherwise have been deposited. The same can be said of much of the Me

Microplastic Contamination of Wild and Captive Flathead Grey Mullet (Mugil cephalus)

PubMed Central

Lui, Ching Yee

2018-01-01

A total of 60 flathead grey mullets were examined for microplastic ingestion. Thirty wild mullets were captured from the eastern coast of Hong Kong and 30 captive mullets were obtained from fish farms. Microplastic ingestion was detected in 60% of the wild mullets, with an average of 4.3 plastic items per mullet, while only 16.7% of captive mullets were found to have ingested microplastics, with an average of 0.2 items per mullet. The results suggested that wild mullets have a higher risk of microplastic ingestion than their captive counterparts. The most common plastic items were fibres that were green in colour and small in size (<2 mm). Polypropylene was the most common polymer (42%), followed by polyethylene (25%). In addition, the abundance of microplastics was positively correlated with larger body size among the mullets. PMID:29587444

Microplastic Contamination of Wild and Captive Flathead Grey Mullet (Mugil cephalus).

PubMed

Cheung, Lewis T O; Lui, Ching Yee; Fok, Lincoln

2018-03-26

A total of 60 flathead grey mullets were examined for microplastic ingestion. Thirty wild mullets were captured from the eastern coast of Hong Kong and 30 captive mullets were obtained from fish farms. Microplastic ingestion was detected in 60% of the wild mullets, with an average of 4.3 plastic items per mullet, while only 16.7% of captive mullets were found to have ingested microplastics, with an average of 0.2 items per mullet. The results suggested that wild mullets have a higher risk of microplastic ingestion than their captive counterparts. The most common plastic items were fibres that were green in colour and small in size (<2 mm). Polypropylene was the most common polymer (42%), followed by polyethylene (25%). In addition, the abundance of microplastics was positively correlated with larger body size among the mullets.

Seasonal movement and habitat use by sub-adult bull trout in the upper Flathead River system, Montana

USGS Publications Warehouse

Muhlfeld, Clint C.; Marotz, Brian

2005-01-01

Despite the importance of large-scale habitat connectivity to the threatened bull trout Salvelinus confluentus, little is known about the life history characteristics and processes influencing natural dispersal of migratory populations. We used radiotelemetry to investigate the seasonal movements and habitat use by subadult bull trout (i.e., fish that emigrated from natal streams to the river system) tracked for varying durations from 1999 to 2002 in the upper Flathead River system in northwestern Montana. Telemetry data revealed migratory (N = 32 fish) and nonmigratory (N = 35 fish) behavior, indicating variable movement patterns in the subadult phase of bull trout life history. Most migrating subadults (84%) made rapid or incremental downriver movements (mean distance, 33 km; range, 6–129 km) to lower portions of the river system and to Flathead Lake during high spring flows and as temperatures declined in the fall and winter. Bull trout subadults used complex daytime habitat throughout the upper river system, including deep runs that contained unembedded boulder and cobble substrates, pools with large woody debris, and deep lake-influenced areas of the lower river system. Our results elucidate the importance of maintaining natural connections and a diversity of complex habitats over a large spatial scale to conserve the full expression of life history traits and processes influencing the natural dispersal of bull trout populations. Managers should seek to restore and enhance critical river corridor habitat and remove migration barriers, where possible, for recovery and management programs.

NPDES Permit for Keller Transport, Inc. Groundwater Remediation Treatment Facility in Montana

EPA Pesticide Factsheets

Under National Pollutant Discharge Elimination System permit number MT0030805, Keller Transport, Inc. is authorized to discharge from its groundwater remediation treatment facility in Lake County, Montana, to Flathead Lake.

NPDES Permit for City of Polson Wastewater Treatment Facility in Montana

EPA Pesticide Factsheets

Under National Pollutant Discharge Elimination System permit number MT-0020559, the City of Polson is authorized to discharge from its wastewater treatment facility located in Lake County, Montana to the Flathead River.

Next-generation sequencing yields the complete mitochondrial genome of the flathead mullet, Mugil cephalus cryptic species in East Australia (Teleostei: Mugilidae).

PubMed

Shen, Kang-Ning; Chen, Ching-Hung; Hsiao, Chung-Der; Durand, Jean-Dominique

2016-09-01

In this study, the complete mitogenome sequence of a cryptic species from East Australia (Mugil sp. H) belonging to the worldwide Mugil cephalus species complex (Teleostei: Mugilidae) has been sequenced by next-generation sequencing method. The assembled mitogenome, consisting of 16,845 bp, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes and a non-coding control region of D-loop. D-loop consists of 1067 bp length, and is located between tRNA-Pro and tRNA-Phe. The overall base composition of East Australia M. cephalus is 28.4% for A, 29.3% for C, 15.4% for G and 26.9% for T. The complete mitogenome may provide essential and important DNA molecular data for further phylogenetic and evolutionary analysis for flathead mullet species complex.

Effectiveness of different species of entomopathogenic nematodes for biocontrol of the Mediterranean flatheaded rootborer, Capnodis tenebrionis (Linné) (Coleoptera: Buprestidae) in potted peach tree.

PubMed

Morton, Ana; Del Pino, Fernando García

2008-02-01

The susceptibility of larvae of the Mediterranean flatheaded rootborer (Capnodis tenebrionis) to 13 isolates of entomopathogenic nematodes was examined using GF-677 potted trees (peachxalmond hybrid) as the host plant. The nematode strains tested included nine Steinernema feltiae, one S. affine, one S. carpocapsae and two Heterorhabditis bacteriophora. Nematodes showed the ability to locate and kill larvae of C. tenebrionis just after they enter into the roots of the tree. S. feltiae strains provided an efficacy ranging from 79.68% to 88.24%. H. bacteriophora strains resulted in control of 71.66-76.47%. S. carpocapsae (B14) and S. affine (Gspe3) caused lower control of C. tenebrionis larvae (62.03% and 34.76%, respectively). The influence of foraging strategy and the use of autochthonous nematodes to control C. tenebrionis larvae inside the roots is discussed.

Artesian pressures and water quality in Paleozoic aquifers in the Ten Sleep area of the Bighorn Basin, north-central Wyoming

USGS Publications Warehouse

Cooley, M.E.

1985-01-01

Major Paleozoic artesian aquifers in the southeastern Bighorn Basin of Wyoming area, in descending order, the Tensleep Sandstone; the Madison Limestone and Bighorn Dolomite, which together form the Madison-Bighorn aquifer; and the Flathead Sandstone. Operating yields commonly are more than 1,000 gallons per minute from flowing wells completed in the Madison-Bighorn aquifer. The initial test of one well indicated a flow of 14,000 gallons per minute. Wellhead pressures range from less than 50 to more than 400 pounds per square inch. Transmissivities are 500-1,900 feet squared per day for the Madison-Bighorn aquifer and 90-325 feet squared per day for the Tensleep and Flathead Sandstones. Despite extensive development for irrigation there have been few decreases in pressure. Some decreases in pressure have occurred in wells completed in the Flathead Sandstone. Fractures along linear structural features result in significant secondary permeability and allow upward interformational movement of water that affects the altitude of the potentiometric surfaces in the Tensleep Sandstone and Madison-Bighorn aquifer. Upward-moving water from the Tensleep and other formations discharges at the land surface as springs along or near these lineations. Water from the aquifers generally contains minimal concentrations of dissolved solids and individual constituents but has excessive hardness. The water is satisfactory for irrigation and other purposes when hardness is not a detrimental factor. Wellhead temperatures range from 11 degrees to 27.5 degrees C, giving a geothermal gradient of about 0.44 degrees C per 100 feet. (USGS)

Geologic map of the Nelson quadrangle, Lewis and Clark County, Montana

USGS Publications Warehouse

Reynolds, Mitchell W.; Hays, William H.

2003-01-01

The geologic map of the Nelson quadrangle, scale 1:24,000, was prepared as part of the Montana Investigations Project to provide new information on the stratigraphy, structure, and geologic history of an area in the geologically complex southern part of the Montana disturbed belt. In the Nelson area, rocks ranging in age from Middle Proterozoic through Cretaceous are exposed on three major thrust plates in which rocks have been telescoped eastward. Rocks within the thrust plates are folded and broken by thrust faults of smaller displacement than the major bounding thrust faults. Middle and Late Tertiary sedimentary and volcaniclastic rocks unconformably overlie the pre-Tertiary rocks. A major normal fault displaces rocks of the western half of the quadrangle down on the west with respect to strata of the eastern part. Alluvial and terrace gravels and local landslide deposits are present in valley bottoms and on canyon walls in the deeply dissected terrain. Different stratigraphic successions are exposed at different structural levels across the quadrangle. In the northeastern part, strata of the Middle Cambrian Flathead Sandstone, Wolsey Shale, and Meagher Limestone, the Middle and Upper Cambrian Pilgrim Formation and Park Shale undivided, the Devonian Maywood, Jefferson, and lower part of the Three Forks Formation, and Lower and Upper Mississippian rocks assigned to the upper part of the Three Forks Formation and the overlying Lodgepole and Mission Canyon Limestones are complexly folded and faulted. These deformed strata are overlain structurally in the east-central part of the quadrangle by a succession of strata including the Middle Proterozoic Greyson Formation and the Paleozoic succession from the Flathead Sandstone upward through the Lodgepole Limestone. In the east-central area, the Flathead Sandstone rests unconformably on the middle part of the Greyson Formation. The north edge, northwest quarter, and south half of the quadrangle are underlain by a succession of rocks that includes not only strata equivalent to those of the remainder of the quadrangle, but also the Middle Proterozoic Newland, Greyson, and Spokane Formations, Pennsylvanian and Upper Mississippian Amsden Formation and Big Snowy Group undivided, the Permian and Pennsylvanian Phosphoria and Quadrant Formations undivided, the Jurassic Ellis Group and Lower Cretaceous Kootenai Formation. Hornblende diorite sills and irregular bodies of probable Late Cretaceous age intrude Middle Proterozoic, Cambrian and Devonian strata. No equivalent intrusive rocks are present in structurally underlying successions of strata. In this main part of the quadrangle, the Flathead Sandstone cuts unconformably downward from south to north across the Spokane Formation into the upper middle part of the Greyson Formation. Tertiary (Miocene?) strata including sandstone, pebble and cobble conglomerate, and vitric crystal tuff underlie, but are poorly exposed, in the southeastern part of the quadrangle where they are overlain by late Tertiary and Quaternary gravel. The structural complexity of the quadrangle decreases from northeast to southwest across the quadrangle. At the lowest structural level (Avalanche Butte thrust plate) exposed in the canyon of Beaver Creek, lower and middle Paleozoic rocks are folded in northwest-trending east-inclined disharmonic anticlines and synclines that are overlain by recumbently folded and thrust faulted Devonian and Mississippian rocks. The Mississippian strata are imbricated adjacent to the recumbent folds. In the east-central part of the quadrangle, a structurally overlying thrust plate, likely equivalent to the Hogback Mountain thrust plate of the Hogback Mountain quadrangle adjacent to the east (Reynolds, 20xx), juxtaposes recumbently folded Middle Proterozoic and unconformably overlying lower Paleozoic rocks on the complexly folded and faulted rocks of the Avalanche Butte thrust plate. The highest structural plate, bounded below

US 93 preconstruction wildlife monitoring field methods handbook : final report.

DOT National Transportation Integrated Search

2006-11-01

The US 93 reconstruction project on the Flathead Indian Reservation in northwest Montana represents one of the most extensive wildlife-sensitive highway design efforts to occur in the continental United States. The reconstruction will include install...

76 FR 77768 - Information Collection; Flathead and McKenzie Rivers and McKenzie National Recreational Trail...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-14

... completed and validated, the hardcopy questionnaires will be discarded. Data will be imported into SPSS (Statistical Package for the Social Sciences) for analysis. The database will be maintained at the respective...

Experimental conical-head abutment screws on the microbial leakage through the implant-abutment interface: an in vitro analysis using target-specific DNA probes.

PubMed

Pita, Murillo S; do Nascimento, Cássio; Dos Santos, Carla G P; Pires, Isabela M; Pedrazzi, Vinícius

2017-07-01

The aim of this in vitro study was to identify and quantify up to 38 microbial species from human saliva penetrating through the implant-abutment interface in two different implant connections, external hexagon and tri-channel internal connection, both with conventional flat-head or experimental conical-head abutment screws. Forty-eight two-part implants with external hexagon (EH; n = 24) or tri-channel internal (TI; n = 24) connections were investigated. Abutments were attached to implants with conventional flat-head or experimental conical-head screws. After saliva incubation, Checkerboard DNA-DNA hybridization was used to identify and quantify up to 38 bacterial colonizing the internal parts of the implants. Kruskal-Wallis test followed by Bonferroni's post-tests for multiple comparisons was used for statistical analysis. Twenty-four of thirty-eight species, including putative periodontal pathogens, were found colonizing the inner surfaces of both EH and TI implants. Peptostreptococcus anaerobios (P = 0.003), Prevotella melaninogenica (P < 0.0001), and Candida dubliniensis (P < 0.0001) presented significant differences between different groups. Means of total microbial count (×10 4 , ±SD) for each group were recorded as follows: G1 (0.27 ± 2.04), G2 (0 ± 0), G3 (1.81 ± 7.50), and G4 (0.35 ± 1.81). Differences in the geometry of implant connections and abutment screws have impacted the microbial leakage through the implant-abutment interface. Implants attached with experimental conical-head abutment screws showed lower counts of microorganisms when compared with conventional flat-head screws. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Home range and space use patterns of flathead catfish during the summer-fall period in two Missouri streams

USGS Publications Warehouse

Vokoun, Jason C.; Rabeni, Charles F.

2005-01-01

Flathead catfish Pylodictis olivaris were radio-tracked in the Grand River and Cuivre River, Missouri, from late July until they moved to overwintering habitats in late October. Fish moved within a definable area, and although occasional long-distance movements occurred, the fish typically returned to the previously occupied area. Seasonal home range was calculated with the use of kernel density estimation, which can be interpreted as a probabilistic utilization distribution that documents the internal structure of the estimate by delineating portions of the range that was used a specified percentage of the time. A traditional linear range also was reported. Most flathead catfish (89%) had one 50% kernel-estimated core area, whereas 11% of the fish split their time between two core areas. Core areas were typically in the middle of the 90% kernel-estimated home range (58%), although several had core areas in upstream (26%) and downstream (16%) portions of the home range. Home-range size did not differ based on river, sex, or size and was highly variable among individuals. The median 95% kernel estimate was 1,085 m (range, 70– 69,090 m) for all fish. The median 50% kernel-estimated core area was 135 m (10–2,260 m). The median linear range was 3,510 m (150–50,400 m). Fish pairs with core areas in the same and neighboring pools had static joint space use values of up to 49% (area of intersection index), indicating substantial overlap and use of the same area. However, all fish pairs had low dynamic joint space use values (<0.07; coefficient of association), indicating that fish pairs were temporally segregated, rarely occurring in the same location at the same time.

The role of multispectral scanners as data sources for EPA hydrologic models

NASA Technical Reports Server (NTRS)

Slack, R.; Hill, D.

1982-01-01

An estimated cost savings of 30% to 50% was realized from using LANDSAT-derived data as input into a program which simulates hydrologic and water quality processes in natural and man-made water systems. Data from the satellite were used in conjunction with EPA's 11-channel multispectral scanner to obtain maps for characterizing the distribution of turbidity plumes in Flathead Lake and to predict the effect of increasing urbanization in Montana's Flathead River Basin on the lake's trophic state. Multispectral data are also being studied as a possible source of the parameters needed to model the buffering capability of lakes in an effort to evaluate the effect of acid rain in the Adirondacks. Water quality in Lake Champlain, Vermont is being classified using data from the LANDSAT and the EPA MSS. Both contact-sensed and MSS data are being used with multivariate statistical analysis to classify the trophic status of 145 lakes in Illinois and to identify water sampling sites in Appalachicola Bay where contaminants threaten Florida's shellfish.

Goldspotted oak borer

Treesearch

M.L. Flint; M. I. Jones; T. W. Coleman; S.J. Seybold

2013-01-01

The goldspotted oak borer (GSOB), Agrilus auroguttatus (Coleoptera: Buprestidae), is a flatheaded borer introduced to San Diego County, California, in the late 1990s or early 2000s and also detected at one site in Riverside County in 2012. It was likely brought into the state on oak firewood collected and transported from the insect's native...

US 93 North post-construction wildlife-vehicle crossing monitoring on the Flathead Indian Reservation between Evaro and Polson, Montana : project summary report.

DOT National Transportation Integrated Search

2016-12-01

The researchers investigated the effectiveness of the mitigation measures in reducing collisions with large wild mammals based on crash and carcass removal data before and after highway reconstruction. The researchers also investigated wildlife use o...

Trunk injury and fungal transport by Agrilus bilineatus, Chrysobothris femorata, and Xyloterinus sp. in oak wilt infected trees in Texas

Treesearch

R. Lewis

1987-01-01

Examinations for trunk borers revealed that over 95% of the oak wilt (Ceratocystis fagacearum) infected trees in Texas were infested with twolined chestnut borers (Agrilus bilineatus) and flatheaded appletree borers (Chrysobothris femorata). Infestations by the ambrosia beetle (Xyloterinus sp...

Deal or No Deal?

ERIC Educational Resources Information Center

Pember, Mary Annette

2006-01-01

Education at a tribal college for non-Native students is "an awfully good deal for states," says Dr. Joseph F. McDonald (Salish/Kootenai), president of Salish Kootenai College on the Flathead reservation in Montana. It may come as a surprise to most Americans, but tribal colleges have been quietly providing higher education to a…

78 FR 37568 - Draft Environmental Impact Statement for Proposed Strategies To Benefit Native Species by...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-21

... Journal, the Missoulian, and on the following Web site: www.mackdays.com . Written comments on the DEIS... Lake and River Fisheries Co-Management Plan, Bull Trout Restoration Plan, Cutthroat Memorandum of... Management Plan. Stakeholders from the Flathead Basin comprise an interdisciplinary team that includes...

78 FR 23741 - Flathead Resource Advisory Committee

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-22

... Kalispell, Montana. The committee is authorized under the Secure Rural Schools and Community Self... recommendations to the Forest Service concerning projects and funding consistent with the Title II of the Act. The meeting is open to the public. The purpose of the meeting is to re-evaluate project proposals for 2013 due...

76 FR 13572 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-14

.... Specifically, it addresses the following flooding sources: Left Bank Overflow Main Stem Skagit River, Left Bank Overflow Main Stem Skagit River/South Fork Skagit River, Left Bank Overflow North Fork Skagit River, Main Stem Skagit River, North Fork Skagit River, Overflow from the Main Stem Skagit River between the North...

77 FR 70413 - Information Collection; Flathead and McKenzie Rivers and McKenzie National Recreational Trail...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-26

... McKenzie National Recreational Trail Visitor Surveys AGENCY: Forest Service, USDA. ACTION: Notice; request... Recreational Trail. Because of the differences in the issues on each River and the need for different... Rivers and McKenzie National Recreational Trail by in-person, written surveys which will be administered...

78 FR 74079 - Fisheries of the Exclusive Economic Zone Off Alaska; Gulf of Alaska; Proposed 2014 and 2015...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-10

... trend for pollock, Pacific cod, deep-water flatfish, Pacific ocean perch, northern rockfish, shortraker..., shallow-water flatfish, rex sole, arrowtooth flounder, flathead sole, rougheye rockfish, demersal shelf... include the TACs for shallow-water flatfish in the West Yakutat and Southeast Outside Districts of the GOA...

Goldspotted oak borer: Field identification guide

Treesearch

S. Hishinuma; T.W. Coleman; M.L. Flint; S.J. Seybold

2011-01-01

The goldspotted oak borer (GSOB), Agrilus auroguttatus (Coleoptera: Buprestidae), is a flatheaded borer new to California that poses a significant threat to oak trees. The pest is native to southeastern Arizona, although a related species occurs in southern Mexico and northern Guatemala. GSOB was first collected and identified in California in 2004 in San Diego County...

78 FR 65962 - Revision of the Land Management Plan for the Flathead National Forest

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-04

... over time. Under the 2012 Planning Rule, the assessment of ecological, social, and economic trends and... environmental impact statement and revised Forest Plan for public review and comment, and the preparation of the final environmental impact statement and revised Forest Plan. The third stage of the process is...

40 CFR Appendix Vi to Part 264 - Political Jurisdictions 1 in Which Compliance With § 264.18(a) Must Be Demonstrated

Code of Federal Regulations, 2011 CFR

2011-07-01

... Cassia Clark Franklin Fremont Jefferson Madison Oneida Power Teton Montana Beaverhead Broadwater Cascade Deer Lodge Flathead Gallatin Granite Jefferson Lake Lewis and Clark Madison Meagher Missoula Park... Sanpete Sevier Summit Tooele Utah Wasatch Washington Wayne Weber Washington Chelan Clallam Clark Cowlitz...

40 CFR Appendix Vi to Part 264 - Political Jurisdictions 1 in Which Compliance With § 264.18(a) Must Be Demonstrated

Code of Federal Regulations, 2010 CFR

2010-07-01

... Cassia Clark Franklin Fremont Jefferson Madison Oneida Power Teton Montana Beaverhead Broadwater Cascade Deer Lodge Flathead Gallatin Granite Jefferson Lake Lewis and Clark Madison Meagher Missoula Park... Sanpete Sevier Summit Tooele Utah Wasatch Washington Wayne Weber Washington Chelan Clallam Clark Cowlitz...

Evaluation of wildlife crossing structures and fencing on US Highway 93 Evaro to Polson Phase I : preconstruction data collection and finalization of evaluation plan : final report.

DOT National Transportation Integrated Search

2006-11-01

The US 93 reconstruction project on the Flathead Indian Reservation in northwest Montana represents one of the most extensive wildlife-sensitive highway design efforts to occur in the continental United States. The reconstruction will include install...

75 FR 65608 - Flathead National Forest-Swan Lake Ranger District, Montana; Wild Cramer Forest Health and Fuels...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-26

... and Fuels Reduction Project to harvest timber, reduce hazardous forest fuels, prescribe burn, and... National Forest System lands before they burn onto private lands; (6) provide forest products to the local... of prescribed ecosystem burning are proposed. Use of existing and construction of temporary and...

78 FR 13161 - Fisheries of the Exclusive Economic Zone Off Alaska; Gulf of Alaska; Final 2013 and 2014 Harvest...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-26

... halibut PSC trawl limits between the trawl gear deep-water and the shallow-water species fishery... for pollock, sablefish, deep-water flatfish, rex sole, Pacific ocean perch, northern rockfish... less than the ABCs for Pacific cod, shallow-water flatfish, arrowtooth flounder, flathead sole, ``other...

Spread of hybridization between native westslope cutthroat trout, Oncorhynchus clarki lewisi, and nonnative rainbow trout, Oncorhynchus mykiss

USGS Publications Warehouse

Hitt, Nathaniel P.; Frissell, Christopher A.; Muhlfeld, Clint C.; Fred W. Allendorf,

2003-01-01

We examined spatial and temporal patterns of hybridization between native westslope cutthroat trout, Oncorhynchus clarki lewisi, and nonnative rainbow trout, O. mykiss, in streams of the Flathead River system in Montana, U.S.A. We detected hybridization in 24 of 42 sites sampled from 1998 to 2001. We found new Oncorhynchus mykiss introgression in seven of 11 sample populations that were determined to be nonhybridized in 1984. Patterns of spatial autocorrelation and linkage disequilibrium indicated that hybridization is spreading among sites and is advancing primarily via post-F1 hybrids. Although hybridized populations were distributed widely throughout the study area, the genetic contribution from O. mykiss decreased with increasing upstream distance from the Flathead River mainstem, suggesting that O. mykiss introgression is spreading in an upstream direction. The spread of hybridization may be constrained more by demographic than by environmental factors, given that (i) hybridized populations generally encompassed the range of environmental variability in nonhybridized populations, and (ii) hybridization status was more strongly associated with neighborhood statistics than measured environmental gradients.

Hungry Horse Dam Wildlife Habitat Enhancement Project: Long-Term Habitat Management Plan, Elk and Mule Deer Winter Range Enhancement, Firefighter Mountain and Spotted Bear Winter Ranges.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Casey, Daniel; Malta, Patrick

1990-06-01

Project goals are to rehabilitate 1120 acres of big game (elk and mule deer, Odocoileus hemionus) winter range on the Hungry Horse and Spotted Bear Districts of Flathead National Forest lands adjacent to Hungry Horse Reservoir. This project represents the initial phase of implementation toward the mitigation goal. A minimum of 547 acres Trust-funded enhancements are called for in this plan. The remainder are part of the typical Forest Service management activities for the project area. Monitor and evaluate the effects of project implementation on the big game forage base and elk and mule deer populations in the project area.more » Monitor enhancement success to determine effective acreage to be credited against mitigation goal. Additional enhancement acreage will be selected elsewhere in the Flathead Forest or other lands adjacent'' to the reservoir based on progress toward the mitigation goal as determined through monitoring. The Wildlife Mitigation Trust Fund Advisory Committee will serve to guide decisions regarding future enhancement efforts. 7 refs.« less

Isolation and Identification of Mosquito (Aedes aegypti) Biting-Deterrent Compounds from the Native American Ethnobotanical Remedy Plant Hierochloë odorata (Sweetgrass).

PubMed

Cantrell, Charles L; Jones, A Maxwell P; Ali, Abbas

2016-11-09

Hierochloë odorata (L.) P. Beauv. (Poaceae), commonly known as sweetgrass, has documented use as an insect repellent by the Flatheads of Montana and Blackfoot of Alberta. Both the Flatheads of Montana and Blackfoot of Alberta would use braided plant material in a sachet in clothing or burn them from one end as incense, air/clothing freshener, and insect repellent. This study evaluated the insect-repellent properties of this plant using an in vitro mosquito Aedes aegypti feeding bioassay-directed approach to identify the compound(s) responsible for the observed activities. Evaluation of crude extracts produced from H. odorata revealed that the hydrodistillate had the highest level of mosquito biting deterrence. Fractionation of this extract, followed by re-evaluation for mosquito biting deterrence, produced many active fractions, which were evaluated by spectroscopic techniques and determined to contain phytol, coumarin, and 2-methoxy-4-vinylphenol. Phytol and coumarin were both determined to be responsible for the Ae. aegypti biting deterrency. Scientific evidence reported here validates its traditional use as a biting-insect deterrent.

Aldrin epoxidation in flathead mullet (Mugil cephalus): possible involvement of CYP1A and CYP3A.

PubMed

Bozcaarmutlu, Azra; Turna, Sema; Sapmaz, Canan; Arinc, Emel; Yenisoy-Karakaş, Serpil

2014-06-01

The primary objective of this study was to determine specific cytochrome P450 isozyme(s) involved in the metabolism of aldrin to its toxic metabolite dieldrin in flathead mullet (Mugil cephalus) liver microsomes. To identify the cytochrome P450 isozyme responsible for the aldrin metabolism in mullet liver, the effects of mammalian-specific cytochrome P450 inhibitors and substrates were determined in the epoxidation reaction of aldrin. CYP3A-related inhibitors, ketoconazole, SKF-525A, and cimetidine, inhibited the metabolism of aldrin. The contribution of CYP1A to the aldrin metabolism was shown by the inhibition of 7-ethoxyresorufin-O-deethylase activity in the presence of aldrin. The results indicate that CY1A and CYP3A are the cytochrome P450s involved in aldrin epoxidase activity in mullet. In addition, the suitability of aldrin epoxidase activity for monitoring of environmental pollution was also assessed in the fish samples caught from four different locations of the West Black Sea coast of Turkey. © 2014 Wiley Periodicals, Inc.

Subsurface geology and porosity distribution, Madison Limestone and underlying formations, Powder River basin, northeastern Wyoming and southeastern Montana and adjacent areas

USGS Publications Warehouse

Peterson, James A.

1978-01-01

To evaluate the Madison Limestone and associated rocks as potential sources for water supplies in the Powder River Basin and adjacent areas, an understanding of the geologic framework of these units, their lithologic facies patterns, the distribution of porosity zones, and the relation between porosity development and stratigraphic facies is necessary. Regionally the Madison is mainly a fossiliferous limestone. However, in broad areas of the eastern Rocky Mountains and western Great Plains, dolomite is a dominant constituent and in places the Madison is almost entirely dolomite. Within these areas maximum porosity development is found and it seems to be related to the coarser crystalline dolomite facies. The porosity development is associated with tabular and fairly continuous crystalline dolomite beds separated by non-porous limestones. The maximum porosity development in the Bighorn Dolomite, as in the Madison, is directly associated with the occurrence of a more coarsely crystalline sucrosic dolomite facies. Well data indicate, however, that where the Bighorn is present in the deeper parts of the Powder River Basin, it may be dominated by a finer crystalline dolomite facies of low porosity. The 'Winnipeg Sandstone' is a clean, generally well-sorted, medium-grained sandstone. It shows good porosity development in parts of the northern Powder River Basin and northwestern South Dakota. Because the sandstone is silica-cemented and quartzitic in areas of deep burial, good porosity is expected only where it is no deeper than a few thousand feet. The Flathead Sandstone is a predominantly quartzose, slightly feldspathic sandstone, commonly cemented with iron oxide. Like the 'Winnipeg Sandstone,' it too is silica-cemented and quartzitic in many places so that its porosity is poor in areas of deep burial. Illustrations in this report show the thickness, percent dolomite, and porosity-feet for the Bighorn Dolomite and the Madison Limestone and its subdivisions. The porosity-feet for the 'Winnipeg' and Flathead Sandstones and four regional geologic sections are also shown.

77 FR 15193 - Fisheries of the Exclusive Economic Zone Off Alaska; Gulf of Alaska; Final 2012 and 2013 Harvest...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-14

..., sablefish, deep-water flatfish, rex sole, Pacific ocean perch, northern rockfish, shortraker rockfish... cod, shallow-water flatfish, arrowtooth flounder, flathead sole, ``other rockfish'' in the Eastern GOA...) guideline harvest levels (GHLs) for Pacific cod so that the ABC is not exceeded. The shallow-water flatfish...

Traditional wisdom: Protecting relationships with wilderness as a cultural landscape

Treesearch

Alan Watson; Roian Matt; Katie Knotek; Daniel R. Williams; Laurie Yung

2011-01-01

Interviews of tribal and nontribal residents of the Flathead Indian Reservation in Montana, U.S., were conducted to contrast the meanings that different cultures attach to the Mission Mountains Tribal Wilderness. Legislation that created a national system of wilderness areas (in 1964 and still growing) was conceived, supported, and enacted by a fairly distinct social...

Brook trout movement in response to temperature, flow, and thermal refugia within a complex Appalachian riverscape

USGS Publications Warehouse

Petty, J. Todd; Hansbarger, Jeff L.; Huntsman, Brock M.; Mazik, Patricia M.

2012-01-01

We quantified movements of brook trout Salvelinus fontinalis and brown trout Salmo trutta in a complex riverscape characterized by a large, open-canopy main stem and a small, closed-canopy tributary in eastern West Virginia, USA. Our objectives were to quantify the overall rate of trout movement and relate movement behaviors to variation in streamflow, water temperature, and access to coldwater refugia. The study area experienced extremely high seasonal, yearly, and among-stream variability in water temperature and flow. The relative mobility of brook trout within the upper Shavers Fork watershed varied significantly depending on whether individuals resided within the larger main stem or the smaller tributary. The movement rate of trout inhabiting the main stem during summer months (50 m/d) was an order of magnitude higher than that of tributary fish (2 m/d). Movement rates of main-stem-resident brook trout during summer were correlated with the maximum water temperature experienced by the fish and with the fish's initial distance from a known coldwater source. For main-stem trout, use of microhabitats closer to cover was higher during extremely warm periods than during cooler periods; use of microhabitats closer to cover during warm periods was also greater for main-stem trout than for tributary inhabitants. Main-stem-resident trout were never observed in water exceeding 19.5°C. Our study provides some of the first data on brook trout movements in a large Appalachian river system and underscores the importance of managing trout fisheries in a riverscape context. Brook trout conservation in this region will depend on restoration and protection of coldwater refugia in larger river main stems as well as removal of barriers to trout movement near tributary and main-stem confluences.

Combining Metabolic Profiling and Gene Expression Analysis to Reveal the Biosynthesis Site and Transport of Ginkgolides in Ginkgo biloba L.

PubMed Central

Lu, Xu; Yang, Hua; Liu, Xinguang; Shen, Qian; Wang, Ning; Qi, Lian-wen; Li, Ping

2017-01-01

The most unique components of Ginkgo biloba extracts are terpene trilactones (TTLs) including ginkgolides and bilobalide. Study of TTLs biosynthesis has been stagnant in recent years. Metabolic profiling of 40 compounds, including TTLs, flavonoids, and phenolic acids, were globally analyzed in leaf, fibrous root, main root, old stem and young stem extracts of G. biloba. Most of the flavonoids were mainly distributed in the leaf and old stem. Most of phenolic acids were generally distributed among various tissues. The total content of TTLs decreased in the order of the leaf, fibrous root, main root, old stem and young stem. The TTLs were further analyzed in different parts of the main root and old stem. The content of TTLs decreases in the order of the main root periderm, the main root cortex and phloem and the main root xylem. In old stems, the content of TTLs in the cortex and phloem was much higher than both the old stem periderm and xylem. The expression patterns of five key genes in the ginkgolide biosynthetic pathway were measured by real-time quantitative polymerase chain reaction (RT-Q-PCR). Combining metabolic profiling and RT-Q-PCR, the results showed that the fibrous root and main root periderm tissues were the important biosynthesis sites of ginkgolides. Based on the above results, a model of the ginkgolide biosynthesis site and transport pathway in G. biloba was proposed. In this putative model, ginkgolides are synthesized in the fibrous root and main root periderm, and these compounds are then transported through the old stem cortex and phloem to the leaves. PMID:28603534

The Glacier National Park: A popular guide to its geology and scenery

USGS Publications Warehouse

Campbell, Marius R.

1914-01-01

The Glacier National Park includes that part of the Front Range of the Rocky Mountains lying just south of the Canadian line, in Teton and Flathead counties, Mont. It is bounded on the west by Flathead River (locally called North Fork), on the south by the Middle Fork of Flathead River and the Great Northern Railway, and on the east by the Blackfeet Indian Reservation. Although this part of the Rocky Mountains has been known since Lewis and Clark crossed the continent in 1805-6, the region later made a park appears not to have been visited by white men until 1853, when Cut Bank Pass was crossed by A. W. Tinkham, one of the Government engineers engaged in exploring a route for the Pacific railroad. Tinkham, who was encamped in the Bitterroot Valley, was ordered to examine Marias Pass, but in traversing Middle Fork of Flathead River along the line of the present railroad he was evidently misled by the large size of the valley of Nyack Creek and ascended that instead of keeping to the right up the main stream. He reported the pass impracticable for railroad construction, and so this region dropped out of public attention for a long time. The next explorers to enter the region were a group of surveyors who, under the direction of American and British commissioners, established the international boundary line along the forty-ninth parallel from the Pacific coast to the main summit of the Rocky Mountains. This party reached the area now included in the park in the summer of 1861, and the stone monument shown in Plate I, B, which they erected on the Continental Divide west of Waterton Lake, still marks a point on the boundary between the United States and Canada. The land on the west side of the range formed a part of the public domain which, until the erection of the park, was open to settlement, but the land on the east originally belonged to the Blackfeet Indians and the white men had no rights upon it. About 1890 copper ore was found near the heads of Quartz and Mineral creeks, and a great boom for this region followed. Many prospectors drifted in, expecting to reap rich rewards from the discovery of mineral deposits and the general development of the region. Several of the main trails were built about this time, and considerable money was spent in prospecting, in opening mines, and in providing machinery to handle the large output of copper ore that was expected. The copper-bearing veins were found to extend through the range to the east side, but prospecting in that part of the mountains was not possible, for the land was included in the Indian reservation. This situation produced a growing discontent among the prospectors, who began to have a strong feeling that the Government should come to their relief by acquiring the coveted land and placing it at their disposal. The urgent demand of the prospectors and promoters was felt in Congress, and a bill was passed providing for the purchase from the Indians of this supposed mineral land for $1,500,000. In accordance with this act, a treaty with the Blackfeet Indians was signed at Browning, Mont., September 26, 1895, and approved by the Senate on June 10, 1896, by which the west line of the reservation was removed from the Continental Divide and was fixed along the eastern points of the spurs of the mountain range, as shown on the accompanying map, and the land so acquired was thrown open to mineral entry only. Under the stimulus of the new territory acquired, active prospecting was carried on for a time, but copper ore was found only in small quantities, and gradually the prospectors and miners drifted away to newer or more promising fields, and the region reverted to its original condition. For a long time it was visited only by hunters in search of big game and by summer visitors who, in order to escape the heat of the plains, were willing to undergo the privations and discomforts of the rude hotels then to be found in the region. Although these mountains had ceased to interest prospectors in search of mineral wealth, they still possessed a fascination for the lovers of natural scenery and almost everyone who visited the region was impressed with its alpine beauty. Again it was brought to the attention of Congress, which was urged to secure it for the use of the people by setting it aside as a national park. On May 11, 1910, President Taft signed the bill creating the Glacier National Park, and this most interesting and beautiful region thus became a permanent playground for the American people.

76 FR 11111 - Fisheries of the Exclusive Economic Zone Off Alaska; Gulf of Alaska; Final 2011 and 2012 Harvest...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-01

.... The Council recommended TACs for 2011 and 2012 that are equal to ABCs for pollock, deep-water flatfish... less than the ABCs for Pacific cod, flathead sole, shallow-water flatfish, arrowtooth flounder, other...-water flatfish, and arrowtooth flounder TACs are set to conserve the halibut PSC limit for use in other...

Feasibility Analysis For Heating Tribal Buildings with Biomass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steve Clairmont; Micky Bourdon; Tom Roche

2009-03-03

This report provides a feasibility study for the heating of Tribal buildings using woody biomass. The study was conducted for the Confederated Salish and Kootenai Tribes of the Flathead Reservation in western Montana. S&K Holding Company and TP Roche Company completed the study and worked together to provide the final report. This project was funded by the DOE's Tribal Energy Program.

Blue Bay: A Tribal Approach to Fighting Alcohol and Drug Abuse. Our Way of Healing.

ERIC Educational Resources Information Center

Native American Development Corp., Washington, DC.

The best means for fighting alcohol abuse in a Native American community is one that has been developed by the community itself. The Blue Bay Healing Center of the Confederated Salish and Kootenai Tribes (Flathead Indian Reservation, Montana) is an example of two tribes taking responsibility for alcoholism and its control. In designing and…

Miller Creek Demonstration Forest - a forest born of fire: A field guide

Treesearch

Penelope A. Latham; Raymond C. Shearer; Kevin L. O' Hara

1998-01-01

Miller Creek, on the Flathead National Forest in northwest Montana, is a demonstration forest, showing up to 30 years of forest change after clearcutting and a wide range of fire treatments in 1967 and 1968. Differences in tree regeneration and vegetation development are explained for units that were clearcut and prescribed burned, clearcut and burned by wildfire,...

Uneasy Terrain: Image, Text, Landscape, and Contemporary Indigenous Artists in the United States

ERIC Educational Resources Information Center

Ohnesorge, Karen

2008-01-01

Like many contemporary Indigenous artists in the United States, Flathead artist Jaune Quick-to-See Smith seeks to clarify existing relationships among race, place, and economics as well as to create new relationships. In particular, she and her peers combine image and text to interrogate the genre of landscape painting as a stage for fantasies of…

Preservice Teachers' Perceptions of Culture in Early Care and Education Programs on a Native American Indian Reservation

ERIC Educational Resources Information Center

Moore, Rita; Gilliard, Jennifer L.

2007-01-01

Four early childhood preservice teachers interviewed and observed teachers and children in early learning centers on the Salish and Kootenai Flathead Indian Reservation in Montana. The purpose of this study was to explore the perceptions of preservice teachers versus those of the caregivers (in-service teachers) regarding the presence of family…

The goldspotted oak borer: revisiting the status of an invasive pest six years after its discovery

Treesearch

Steve Seybold; Tom W. Coleman

2015-01-01

The goldspotted oak borer, Agrilus auroguttatus (Coleoptera: Buprestidae), was first associated with oak mortality in San Diego County, California in May of 2008. Since that time, a research and survey program has outlined the biology of this flatheaded borer in the invaded and native habitats; delimited the invaded range; and developed the...

Insect-caused deterioration of windthrown timber in northern California, 1963-1964

Treesearch

Boyd E. Wickman

1965-01-01

The principal tree degrade was caused by blue stain fungi introduced by bark beetles and flatheaded borers. Roundheaded borers caused the most serious wood boring. Smaller trees suffered more degrade than larger, and degrade was more severe below 5,000 feet elevation. Degrade due to insects was not as heavy as expected, probably because of cool summer weather and low...

Hungry Horse Dam Fisheries Mitigation : Fish Passage and Habitat Improvement in the Upper Flathead River Basin, 1991-1996 Progress Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knotek, W.Ladd; Deleray, Mark; Marotz, Brian L.

1997-08-01

In the past 50 years, dramatic changes have occurred in the Flathead Lake and River system. Degradation of fishery resources has been evident, in part due to deterioration of aquatic habitat and introduction of non-endemic fish and invertebrate species. Habitat loss has been attributed to many factors including the construction and operation of Hungry Horse Dam, unsound land use practices, urban development, and other anthropogenic and natural disturbances. Fish migration has also been limited by barriers such as dams and impassible culverts. Cumulatively, these factors have contributed to declines in the distribution and abundance of native fish populations. Recovery ofmore » fish populations requires that a watershed approach be developed that incorporates long-term aquatic habitat needs and promotes sound land use practices and cooperation among natural resource management agencies. In this document, the authors (1) describe completed and ongoing habitat improvement and fish passage activities under the Hungry Horse Fisheries Mitigation Program, (2) describe recently identified projects that are in the planning stage, and (3) develop a framework for identifying prioritizing, implementing, and evaluating future fish habitat improvement and passage projects.« less

More than a corridor: use of a main stem stream as supplemental foraging habitat by a brook trout metapopulation.

PubMed

Huntsman, Brock M; Petty, J Todd; Sharma, Shikha; Merriam, Eric R

2016-10-01

Coldwater fishes in streams, such as brook trout (Salvelinus fontinalis), typically are headwater specialists that occasionally expand distributions downstream to larger water bodies. It is unclear, however, whether larger streams function simply as dispersal corridors connecting headwater subpopulations, or as critical foraging habitat needed to sustain large mobile brook trout. Stable isotopes (δ(13)C and δ(15)N) and a hierarchical Bayesian mixing model analysis was used to identify brook trout that foraged in main stem versus headwater streams of the Shavers Fork watershed, West Virginia. Headwater subpopulations were composed of headwater and to a lesser extent main stem foraging individuals. However, there was a strong relationship between brook trout size and main stem prey contributions. The average brook trout foraging on headwater prey were limited to 126 mm standard length. This size was identified by mixing models as a point where productivity support switched from headwater to main stem dependency. These results, similar to other studies conducted in this watershed, support the hypothesis that productive main stem habitat maintain large brook trout and potentially facilitates dispersal among headwater subpopulations. Consequently, loss of supplementary main stem foraging habitats may explain loss of large, mobile fish and subsequent isolation of headwater subpopulations in other central Appalachian watersheds.

Clinical analysis of eight patients with blunt main stem bronchial injuries.

PubMed

Lei, Jie; Zhao, Jinbo; Tian, Feng; Wang, Xiaoping; Zhou, Yongan; Li, Xiaofei; Wang, Jian

2017-01-01

Blunt main stem bronchial injuries are rare but potentially life-threatening injuries in clinical. The aim of this study was to sum up the experience on diagnosis and treatment of blunt main stem bronchial injuries. This report retrospective1y analyzed eight cases of main stem bronchial injuries induced by blunt chest trauma between 2013 and 2016 in Tangdu Hospital, Fourth Military Medical University. There were eight patients, including four men and four women. The definitive diagnosis was confirmed by fibrobronchoscopy. Mean time between injury and treatment in our hospital was 4.25 days (range, 1-12 days). Mean length of airway tear was 1.04 cm (range, 0.5-2 cm). In four patients there was an injury to the left main stem bronchus, in three patients to the right main stem bronchus and in one patient to the ambilateral main stem bronchus. Emergent operation was performed in two patients and elective operation in six patients. End to end bronchial anastomosis was performed via right thoracotomy in two patients and via left thoracotomy in three patients, and primary repair was performed via right thoracotomy in two patients and via left thoracotomy in the remaining one patient. There was no death in this group. Seven patients had no complications and were able to take part in normal activities. One patient suffered from anastomotic stricture after operation was healed by granulation tissue resection and cryotherapy under fibrobronchoscopy. Fibrobronchoscopy is able to define the blunt main stem bronchial injuries precisely and surgical approach is the preferred method for patients with these life-threatening complications.

Mapping tradeoffs in values at risk at the interface between wilderness and non-wilderness lands

Treesearch

Alan Watson; Roian Matt; Tim Waters; Kari Gunderson; Steve Carver; Brett Davis

2009-01-01

On the Flathead Indian Reservation in Montana, U.S., the Mission Mountains Tribal Wilderness is bordered by a buffer zone. To successfully improve forest health within that buffer zone and restore fire in the wilderness, the managing agency and the public need to work together to find solutions to increasingly threatening fuel buildups. A combination of qualitative,...

75 FR 11749 - Fisheries of the Exclusive Economic Zone Off Alaska; Gulf of Alaska; Final 2010 and 2011 Harvest...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-12

... TACs for 2010 and 2011 that are equal to ABCs for pollock, deep-water flatfish, rex sole, sablefish... recommended TACs for 2010 and 2011 that are less than the ABCs for Pacific cod, flathead sole, shallow-water... that the sum of all State and Federal water Pacific cod removals from the GOA not exceed ABC...

Miller Creek Demonstration Forest ecology activities - a teachers supplement to the field guide

Treesearch

Bill Schustrom; Reed Kuennen; Raymond C. Shearer

1998-01-01

Miller Creek, on the Flathead National Forest in northwestern Montana, is a demonstration forest, showing up to 30 years of forest change. This teachers supplement to the educational field guide (Miller Creek Demonstration Forest - a forest born of fire: a field guide; Gen. Tech. Rep. RMRS-GTR-7, 1998) outlines eight field and classroom activities that teach students a...

77 FR 56798 - Fisheries of the Exclusive Economic Zone Off Alaska; Revise Maximum Retained Amounts for...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-14

... 709 West 9th Street, Room 420A, Juneau, AK. Comments must be submitted by one of the above methods to... the GOA. In 1997, NMFS increased the MRAs for pollock and Pacific cod from zero to 5 percent when... arrowtooth flounder fishery from zero to 20 percent for deep-water flatfish, rex sole, flathead sole, shallow...

CCE fire regimes and their management

Treesearch

Robert E. Keane; Carl Key

2007-01-01

A spectacular forest in the center of the CCE cuts a 15- by 5-km swath along the Flathead River's South Fork around Big Prairie in the middle of the Bob Marshall Wilderness Area in Montana (Figure 13- 1). This wide valley bottom, which contains two patches (of about 1,000 ha each) of the last vestiges of the historic ponderosa pine ecosystem in the CCE, provides a...

Final report: Imagining Fire Futures - An interactive, online learning activity for high school and college students

Treesearch

Jane Kapler Smith

2014-01-01

In IMAGINING FIRE FUTURES, students in a high school or college class use model results to develop a vision of the future for Flathead County, Montana. This is a rural area in the northern Rocky Mountains where more than half of the landscape is covered by wildland ecosystems that have evolved with and are shaped by wildland fire.

BIONETS (THREE STACKED HYDRAULIC FRACTURES) CONTAINING SOLID OXYGEN SOURCE (SOS), ISOLITE (FIRED DIATOMACIOUS EARTH) AND BACTERIAL STRAIN PM1 TO STIMULATE IN SITU BIOREMEDIATION OF MTBE AND BTEX IN SOILS AND GROUNDWATER

EPA Science Inventory

Collaboration with Office of Research and Development, Region 8, Foremost Solutions, University of California, and Native American Flathead Tribe lead to the development and demonstration of this treatment technology. In place BioNetsTM were developed, initiated, studied and used...

Host associations and genomic diversity of Borrelia hermsii in an endemic focus of tick-borne relapsing fever in western North America.

PubMed

Johnson, Tammi L; Fischer, Robert J; Raffel, Sandra J; Schwan, Tom G

2016-11-10

An unrecognized focus of tick-borne relapsing fever caused by Borrelia hermsii was identified in 2002 when five people became infected on Wild Horse Island in Flathead Lake, Montana. The terrestrial small mammal community on the island is composed primarily of pine squirrels (Tamiasciurus hudsonicus) and deer mice (Peromyscus maniculatus), neither of which was known as a natural host for the spirochete. Thus a 3-year study was performed to identify small mammals as hosts for B. hermsii. Small mammals were captured alive on two island and three mainland sites, blood samples were collected and examined for spirochetes, and serological tests performed to detect anti-B. hermsii antibodies. Ornithodoros hermsi ticks were collected and fed on laboratory mice to assess infection. Genomic DNA samples from spirochetes isolated from infected mammals and ticks were analyzed by multilocus sequence typing. Eighteen pine squirrels and one deer mouse had detectable spirochetemias when captured, from which 12 isolates of B. hermsii were established. Most pine squirrels were seropositive, and the five species of sciurids combined had a significantly higher prevalence of seropositive animals than did the other six small mammal species captured. The greater diversity of small mammals on the mainland in contrast to the islands demonstrated that other species in addition to pine squirrels were also involved in the maintenance of B. hermsii at Flathead Lake. Ornithodoros hermsi ticks produced an additional 12 isolates of B. hermsii and multilocus sequence typing identified both genomic groups of B. hermsii described previously, and identified a new genomic subdivision. Experimental infections of deer mice with two strains of B. hermsii demonstrated that these animals were susceptible to infection with spirochetes belonging to Genomic Group II but not Genomic Group I. Pine squirrels are the primary hosts for the maintenance of B. hermsii on the islands in Flathead Lake, however serological evidence showed that numerous additional species are also involved on the mainland. Future studies testing the susceptibility of several small mammal species to infection with different genetic types of B. hermsii will help define their role as hosts in this and other endemic foci.

Breeding ecology of the redhead duck in western Montana

USGS Publications Warehouse

Lokemoen, J.T.

1966-01-01

The habits of the redhead duck (Aythya americana) were studied in the Flathead Valley of western Montana in 1960 and 1961 to determine their habitat preferences in this pothole breeding ground. The 2,600-acre study area, surrounding the Ninepipe Reservoir, contained 686 potholes. Redheads usually were paired by the time they arrived on the study area in March. The average density of redhead breeding pairs was 25 pairs per square mile. For all spring activities except nesting, the birds used large, deep, open potholes or breeding-pair potholes. The several breeding-pair potholes and the nesting pothole utilized by the pair comprised their home range. Starting in late April, the pairs moved about the home range as the hens selected nesting sites, usually in the dense emergent vegetation of small, shallow potholes. Hard-stem bulrush (Scirpus acutus) and cat-tail (Typha latifolia) were preferred nesting cover. Redhead nesting success was only 15 percent, a low rate apparently caused by degenerate nesting behavior complicated by high redhead density, a lack of suitable nest hosts, and certain habitat deficiencies. By late June most drakes and unsuccessful hens had moved from the potholes to nearby reservoirs. All successful hens led their newly hatched broods from the nesting potholes to larger brood potholes and many eventually moved to the reservoir. By mid-July virtually all redheads had moved from the potholes to the reservoirs, where they remained until fall migration.

Recruitment variation of crappies in response to hydrology of Tennessee reservoirs

USGS Publications Warehouse

Sammons, S.M.; Bettoli, P.W.; Isermann, D.A.; Churchill, T.N.

2002-01-01

Black crappies Pomoxis nigromaculatus and white crappies P. annularis were sampled to index recruitment in seven Tennessee reservoirs (four main-stem and three tributary storage impoundments). Crappie recruitment in tributary storage impoundments appeared to be consistently higher in years of high discharge during the prespawn period (1 January-31 March). A similar relation was found in one main-stem impoundment; however, crappie recruitment in two main-stem impoundments was inversely related to discharge during the spawning period (1 April-30 May), and little recruitment variation was found in the fourth main-stem impoundment. In general, reservoir hydrology appeared to have a stronger effect on crappie recruitment in tributary storage impoundments than in main-stem impoundments, possibly because recruitment was more variable in tributary systems. Thus, it is likely that crappie populations will rarely have strong year-classes simultaneously over a wide geographic area or even within a single watershed.

An Investigation of How Culture Shapes Curriculum in Early Care and Education Programs on a Native American Indian Reservation: "The Drum Is Considered the Heartbeat of the Community"

ERIC Educational Resources Information Center

Gilliard, Jennifer L.; Moore, Rita A.

2007-01-01

This article investigates how culture shapes instruction in three early care and education programs on the Flathead Indian Reservation. Interviews with eight early childhood teachers as well as classroom observations were conducted. The investigation is framed by the following research question: How does the culture of the family and community…

The Federal Cylinder Project: A Guide to Field Cylinder Collections in Federal Agencies. Volume 3, Great Basin/Plateau Indian Catalog, Northwest Coast/Arctic Indian Catalog.

ERIC Educational Resources Information Center

Gray, Judith A., Ed.

Two catalogs inventory wax cylinder collections, field recorded among Native American groups, 1890-1942. The catalog for Great Basin and Plateau Indian tribes contains entries for 174 cylinders in 7 collections from the Flathead, Nez Perce, Thompson/Okanagon, Northern Ute, and Yakima tribes. The catalog for Northwest Coast and Arctic Indian tribes…

Economic Analysis of Energy-Efficiency Measures: Tribal Case Studies with the Yurok Tribe, the Confederated Salish and Kootenai Tribes of the Flathead Reservation, and the Pascua Yaqui Tribe

ERIC Educational Resources Information Center

Acker, Thomas L.; Auberle, William M.; Eastwood, John D.; Laroche, David R.; Slack, Robert P.; Smith, Dean H.; Ormond, Amanda S.

2005-01-01

The results of three energy-efficiency case studies conducted with three different Native American tribes in the western United States is presented. The case studies demonstrate that energy-efficiency is economically feasible and has the potential to reduce air pollution, and can potentially help tribes meet other important tribal objectives.

Simulating future residential property losses from wildfire in Flathead County, Montana: Chapter 1

USGS Publications Warehouse

Prato, Tony; Paveglio, Travis B; Barnett, Yan; Silverstein, Robin; Hardy, Michael; Keane, Robert; Loehman, Rachel A.; Clark, Anthony; Fagre, Daniel B.; Venn, Tyron; Stockmann, Keith

2014-01-01

Wildfire damages to private residences in the United States and elsewhere have increased as a result of expansion of the wildland-urban interface (WUI) and other factors. Understanding this unwelcome trend requires analytical frameworks that simulate how various interacting social, economic, and biophysical factors influence those damages. A methodological framework is developed for simulating expected residential property losses from wildfire [E(RLW)], which is a probabilistic monetary measure of wildfire risk to residential properties in the WUI. E(RLW) is simulated for Flathead County, Montana for five, 10-year subperiods covering the period 2010-2059, under various assumptions about future climate change, economic growth, land use policy, and forest management. Results show statistically significant increases in the spatial extent of WUI properties, the number of residential structures at risk from wildfire, and E(RLW) over the 50-year evaluation period for both the county and smaller subareas (i.e., neighborhoods and parcels). The E(RLW) simulation framework presented here advances the field of wildfire risk assessment by providing a finer-scale tool that incorporates a set of dynamic, interacting processes. The framework can be applied using other scenarios for climate change, economic growth, land use policy, and forest management, and in other areas.

Long-term atmospheric deposition of nitrogen, phosphorus and sulfate in a large oligotrophic lake

PubMed Central

Craft, James A.; Stanford, Jack A.

2015-01-01

We documented significantly increasing trends in atmospheric loading of ammonium (NH4) and nitrate/nitrite (NO2/3) and decreasing trends in total phosphorus (P) and sulfate (SO4) to Flathead Lake, Montana, from 1985 to 2004. Atmospheric loading of NO2/3 and NH4 increased by 48 and 198% and total P and SO4 decreased by 135 and 39%. The molar ratio of TN:TP also increased significantly. Severe air inversions occurred periodically year-round and increased the potential for substantial nutrient loading from even small local sources. Correlations between our loading data and various measures of air quality in the basin (e.g., particulate matter <10 µm in size, aerosol fine soil mass, aerosol nutrient species, aerosol index, hectares burned) suggest that dust and smoke are important sources. Ammonium was the primary form of N in atmospheric deposition, whereas NO3 was the primary N form in tributary inputs. Atmospheric loading of NH4 to Flathead Lake averaged 44% of the total load and on some years exceeded tributary loading. Primary productivity in the lake is colimited by both N and P most of the year; and in years of high atmospheric loading of inorganic N, deposition may account for up to 6.9% of carbon converted to biomass. PMID:25802810

Long-term atmospheric deposition of nitrogen, phosphorus and sulfate in a large oligotrophic lake.

PubMed

Ellis, Bonnie K; Craft, James A; Stanford, Jack A

2015-01-01

We documented significantly increasing trends in atmospheric loading of ammonium (NH4) and nitrate/nitrite (NO2/3) and decreasing trends in total phosphorus (P) and sulfate (SO4) to Flathead Lake, Montana, from 1985 to 2004. Atmospheric loading of NO2/3 and NH4 increased by 48 and 198% and total P and SO4 decreased by 135 and 39%. The molar ratio of TN:TP also increased significantly. Severe air inversions occurred periodically year-round and increased the potential for substantial nutrient loading from even small local sources. Correlations between our loading data and various measures of air quality in the basin (e.g., particulate matter <10 µm in size, aerosol fine soil mass, aerosol nutrient species, aerosol index, hectares burned) suggest that dust and smoke are important sources. Ammonium was the primary form of N in atmospheric deposition, whereas NO3 was the primary N form in tributary inputs. Atmospheric loading of NH4 to Flathead Lake averaged 44% of the total load and on some years exceeded tributary loading. Primary productivity in the lake is colimited by both N and P most of the year; and in years of high atmospheric loading of inorganic N, deposition may account for up to 6.9% of carbon converted to biomass.

Juvenile groundfish habitat in Kachemak Bay, Alaska, during late summer

USGS Publications Warehouse

Abookire, Alisa A.; Piatt, John F.; Norcross, Brenda L.

2001-01-01

We investigated the habitat of juvenile groundfishes in relation to depth, water temperature, and salinity in Kachemak Bay, Alaska. Stations ranging in depth from 10 to 70 m and with sand or mud-sand substrates were sampled with a small-meshed beam trawl in August-September of 1994 to 1999. A total of 8,201 fishes were captured, comprising at least 52 species. Most fishes (91%) had a total length 5% of the total catch) were flathead sole Hippoglossoides elassodon, slim sculpin Radulinus asprellus, Pacific halibut Hippoglossus stenolepis, and arrowtooth flounder Atheresthes stomias. Depth accounted for most of the spatial variability in juvenile groundfish abundance, and neither temperature nor salinity was correlated with fish abundance. Juvenile groundfishes concentrated in either shallow (less than or equal to 20 m) or deep (50-70 m) water, with co-occurrence of some species between 30-40 m. Shallow fishes were the rock soles, Pacific halibut, and great sculpin Myoxocephalus polyacanthocephalus. Deep species were flathead sole, slim sculpin, spinycheek starsnout Bathyagonus infraspinatus, rex sole Glyptocephalus zachirus, tadpole sculpin Psychrolutes paradoxus, and whitebarred prickleback Poroclinus rothrocki. This 6-year study provides baseline data on relative abundance and distribution of juvenile groundfishes in Kachemak Bay and may provide a useful tool for predicting the presence of species in similar habitats in other areas of Alaska.

A NEW SPECIES OF CARYOSPORA (APICOMPLEXA: EIMERIIDAE) FROM THE FLATHEAD SNAKE, TANTILLA GRACILIS (OPHIDIA: COLUBRIDAE), IN SOUTHEASTERN OKLAHOMA

PubMed Central

McAllister, Chris T.; Roehrs, Zachary P.; Seville, R. Scott

2012-01-01

A single flathead snake, Tantilla gracilis, collected in early October 2010 from Choctaw County, Oklahoma, was found to harbor an undescribed species of Caryospora. Oocysts of Caryospora choctawensis n. sp. were spherical to subspherical, 15.8 × 15.0 (14–18 × 14–16) μm with a thick bilayered wall and a shape index (length/width) of 1.1. A micropyle and an oocyst residuum are absent but prominent Stieda and bubble-like sub-Stieda bodies were present as well as a bilobed polar granule near the oocyst wall. Sporocysts were ovoidal, 10.8 × 9.0 (10–12 × 8–9) μm with a shape index of 1.3. The sporocyst residuum was spherical and composed of a cluster of granules often membrane-bound. This is the second time a caryosporan species has been reported from T. gracilis, but the first coccidian ever described from a reptilian host in Oklahoma. Additional T. gracilis from Arkansas (n = 6), Oklahoma (n = 1), and Texas (n = 7) were examined and a single specimen from Newton County, Arkansas, harbored Caryospora gracilis Upton, McAllister, Trauth, and Bibb, 1992, previously reported from T. gracilis collected in Arkansas and Texas. PMID:22191621

Stem Cells

MedlinePlus

Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair ... body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

Kokanee Stocking and Monitoring, Flathead Lake, 1993-1994 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deleray, Mark; Fredenberg, Wade; Hansen, Barry

1995-07-01

One mitigation goal of the Hungry Horse Dam fisheries mitigation program, funded by the Bonneville Power Administration, is to replace lost production of 100,000 adult kokanee in Flathead Lake. The mitigation program calls for a five-year test to determine if kokanee can be reestablished in Flathead Lake. The test consists. of annual stocking of one million hatchery-raised yearling kokanee. There are three benchmarks for judging the success of the kokanee reintroduction effort: (1) Post-stocking survival of 30 percent of planted kokanee one year after stocking; (2) Yearling to adult survival of 10 percent (100,000 adult salmon); (3) Annual kokanee harvestmore » of 50,000 or more fish per year by 1998, with an average length of 11 inches or longer for harvested fish, and fishing pressure of 100,000 angler hours or more. Kokanee were the primary sport fish species in the Flathead Lake fishery in the early 1900s, and up until the late 1980s when the population rapidly declined in numbers and then disappeared. Factors identified which influenced the decline of kokanee are the introduction of opossum shrimp (Mysis relicta), hydroelectric operations, overharvest through angling, and competition and/or predation by lake trout (Salvelinus namaycush) and lake whitefish (Coregonur clupeaformis). The purpose of this report was to summarize the stocking program and present monitoring results from the 1993 and 1994 field seasons. In June 1993, roughly 210,000 yearling kokanee were stocked into two bays on the east shore of Flathead Lake. Following stocking, we observed a high incidence of stocked kokanee in stomach samples from lake trout captured in areas adjacent to the stocking sites and a high percentage of captured lake trout containing kokanee. Subsequent monitoring concluded that excessive lake trout predation precluded significant survival of kokanee stocked in 1993. In June 1994, over 802,000 kokanee were stocked into Big Arm Bay. The combination of near optimum water temperatures, an upsurge in the abundance of Duphniu rhorum, and saturation planting in an area believed to have lower lake trout densities was expected to maximize short-term survival of stocked kokanee. A net-pen experiment demonstrated that yearling hatchery kokanee, in the absence of predation, adjusted to conditions in Flathead Lake and utilized available zooplankton during June and July without substantial poststocking mortality. Kokanee captured after several months in the lake exhibited good growth and condition. We concluded that the food supply in Big Arm Bay was not limiting survival of stocked kokanee. The 1994 monitoring objective was to quantify lake trout predation of kokanee in Big Arm Bay in the first eight weeks following stocking. There were three components needed to quantify predation; estimated number of lake trout in Big Arm Bay, average number of kokanee consumed by lake trout, and estimated time required for lake trout to digest kokanee. As in the previous year, the monitoring results from the 1994 kokanee plant demonstrated that lake trout predation is the primary factor reducing survival of stocked kokanee. We estimated that lake trout consumed a minimum of 232,000 kokanee in Big Arm Bay during the first eight weeks following stocking. This represents 29 percent of kokanee planted. The consumption estimate was based on a hydroacoustic estimate for lake trout abundance (7,850 fish over 300 mm in total length), an incidence of kokanee per lake trout stomach sample which ranged from 2.99 to 0.22 fish, and a gastric evacuation rate of 47 hours for lake trout to digest consumed kokanee. Due to hydroacoustic limitations in identifying bottom-oriented lake trout, we underestimated the true abundance of lake trout, which led to an underestimate of kokanee mortality. By fall of 1994, we estimated that an additional 12.7 percent of surviving kokanee matured, based on observations of similar-sized fish in the hatchery. Thus, up to 72,000 additional fish were removed from the population due to early maturation. Adding the loss due to predation in the first eight weeks (232,000) to the loss due to early maturation (72,000), we accounted for mortality of at least 304,000 (38 percent) of the original 802,000 fish planted. These estimates did not account for additional losses, including predation outside Big Arm Bay, predation in the months following July, and predation from species other than lake trout, such as bull trout and northern squawfish. We documented lake trout predation of kokanee from June through October, and predation by fish species other than lake trout. One of the program goals is to achieve post-stocking survival of 30 percent one year after planting. Based on observations of the 1994 program, it is unlikely we will achieve this level of survival from the 1994 plant.« less

Point-of-care sonographic detection of left endobronchial main stem intubation and obstruction versus endotracheal intubation.

PubMed

Blaivas, Michael; Tsung, James W

2008-05-01

Determining the correct position of endotracheal tubes in critically ill patients may be complicated by external factors such as noise, body habitus, and the need for ongoing resuscitation. Multiple detection techniques have been developed to determine the correct endotracheal tube position, recently including the use of sonography to evaluate lung expansion and diaphragmatic excursion. These techniques have also been applied to diagnosis of right endobronchial main stem intubation, which may be confused with a unilateral pneumothorax in some cases. We describe the sonographic findings in a case series of endobronchial main stem intubations and obstruction, highlighting the utility of this sonographic application. Previous literature and future applications are discussed. Sonographic detection of the sliding lung sign, the lung pulse, and diaphragmatic excursion can accurately detect main stem bronchial intubation as well as bronchial obstruction. Clinical use of lung sonography may decrease the need for chest radiography and may allow more rapid diagnosis of main stem intubation and bronchial obstruction.

Spatial and temporal sensitivity of hydrogeomorphic responceand recovery to deforestation, Agriculture, and floods

USGS Publications Warehouse

Fitzpatrick, F.A.; Knox, J.C.

2000-01-01

Clear-cut logging followed by agricultural activity caused hydrologic and geomorphic changes in North Fish Creek, a Wisconsin tributary to Lake Superior. Hydro-geomorphic responses to changes in land use were sensitive to the location of reaches along the main stem and to the relative timing of large floods. Hydrologic and sediment-load modeling indicates that flood peaks were three times larger and sediment loads were five times larger during maximum agricultural activity in the 1920s and 1930s than prior to about 1890, when forest cover was dominant. Following logging, overbank sedimentation rates in the lower main stem increased four to six times above pre-settlement rates. Accelerated streambank and channel erosion in the upper main stem have been and continue to be primary sources of sediment to downstream reaches. Extreme floods in 1941 and 1946, followed by frequent moderate floods through 1954, caused extensive geomorphic changes along the entire main stem. Sedimentation rates in the lower main stem may have decreased in the last several decades as agricultural activity declined. However, geomorphic recovery is slow, as incised channels in the upper main stem function as efficient conveyors of watershed surface runoff and thereby continue to promote flooding and sedimentation problems downstream. [Key words: fluvial geomorphology, floods, erosion, sedimentation, deforestation, agriculture.].

South Fork Flathead Watershed Westslope Cutthroat Trout Conservation Program, Annual Report 2002.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grisak, Grant; Marotz, Brian

2003-06-01

In 1999, Montana Fish, Wildlife & Parks (MFWP) began a program aimed at conserving the genetically pure populations of westslope cutthroat trout in the South Fork Flathead River drainage. The objective of this program is to eliminate all of the exotic and hybrid trout that threaten the genetically pure westslope cutthroat populations in the South Fork Flathead. The exotic and hybrid trout populations occur in several headwater lakes and their outflow streams. In 2001 MFWP released a draft environmental assessment, pursuant to the Montana Environmental Policy Act (MEPA), that addressed the use of motorized equipment to deliver personnel and materialsmore » to some of these lakes in the Bob Marshall and Great Bear Wildernesses (Grisak 2001). After a 30-day public comment period, MFWP determined that the complexity of issues was too great and warranted a more detailed analysis. These issues included transportation options for personnel, equipment and materials, the use of motorized equipment in wilderness, fish removal methods, fish stocking, and the status and distribution of amphibian populations in the project area. Because the program also involves the U.S. Forest Service (USFS) and Bonneville Power Administration (BPA), the environmental analysis needs to comply with the National Environmental Policy Act (NEPA). In October 2001, pursuant to NEPA, MFWP, along with the USFS and BPA initiated an environmental assessment to address these issues. In June 2002, the three agencies determined that the scope of these issues warranted an Environmental Impact Statement. This specialist report describes the logistical, technical and biological issues associated with this project and provides an analysis of options for fish removal, transportation and fish stocking. It further analyzes issues and concerns associated with amphibian populations and creating new domesticated stocks of westslope cutthroat trout. Finally, this document provides a description of each lake, the best method of fish removal that would achieve the goals of the project, logistics for carrying out the fish removal, and the immediate management direction for each lake following fish removal. The USFS is preparing a specialist report detailing land management issues that relate to National Forest, designated Hiking Areas, and Wilderness. Information from these two documents will be used by BPA to prepare an Environmental Impact Statement.« less

Analysis and Interpretation of Artifact Collections from Site 3CT271, Randolph Estate Development, Crittenden County, Arkansas

DTIC Science & Technology

1991-02-01

The county has many streams, bayous, and lakes . Major drainages in Crittenden County include the Tyronza River, Fifteenmile Bayou, Tenmile Bayou, and...and canadian geese (Bra nta canadensis). -Fish from the larger streams, oxbow lakes , and beaver ponds, U such as the flathead catfish, alligator gar...type site for the Big Lake phase., Similar components have been recently recognized along the Mississippi River drainage just east of the project area

Determination of organochlorine pesticide concentrations in flathead mullet (Mugil cephalus) caught from the western Black Sea coast of Turkey.

PubMed

Bozcaarmutlu, Azra; Turna, Sema; Sapmaz, Canan; Yenisoy-Karakaş, Serpil

2014-12-01

The objective of this study was to determine the levels of 14 organochlorine pesticides (OCPs) in flathead mullet (Mugil cephalus) caught from the western Black Sea coast of Turkey. The fish samples were caught from five different locations of the western Black Sea coast of Turkey in August 2009. Organochlorine pesticides were extracted from the liver tissues, and then the levels of OCPs were measured using gas chromatography with an electron capture detector. Organochlorine pesticides were detected in all locations. The levels of total OCPs in fish samples ranged between 0.224 and 1.103 μg g(-1) dry weight in the western Black Sea coast of Turkey. DDT, beta-HCH, and endosulfan I were the dominant OCPs in the fish samples. The levels of DDT in fish samples ranged between 0.081 and 0.186 μg g(-1) dry weight. The levels of total HCH in fish samples ranged between 0.007 and 0.376 μg g(-1) dry weight in the western Black Sea coast of Turkey. Although the usage of OCPs was banned in Turkey, the results of this study clearly indicated the presence of OCPs in the western Black Sea coast of Turkey and exposure of living organisms to these chemicals.

Analysis and Interpretation of Artifact Collections from four Archaeological Sites within the Country Club Gardens Permit Area, West Memphis, Crittenden County, Arkansas

DTIC Science & Technology

1990-12-01

Excavation at Chucallssa (40SY1). Laboratory work at C.H. Nash Museum. Testing of suspected mound site near Reelfoot Lake , Obion County, Tennessee...Ferguson 1974:2). The county has many streams, bayov s, and lakes . Major drainages in Crittenden County include the Tyronza River, Fifteenmile Bayou...Branta canadensis). Fish from the larger streams, oxbow lakes and beaver ponds, such as the flathead catfish, alligator gar, drum, buffalo, largemouth

Archaeological Investigations at 3SF332: An Early Mississippian and Tenant Period Site on Cutoff Bayou, St. Francis County, Arkansas

DTIC Science & Technology

1991-06-01

Chucalissa (40SY1). Laboratory work at C.H. Nash Museum. Testing of suspected mound site near Reelfoot Lake , Obion County, Tennessee. Archaeological...geese (Branta canadensis). Fish from the larger streams, oxbow lakes , and beaver ponds, such as the flathead catfish, alligator gar, drum, buffalo...Zebree site in northeast Arkansas (Morse and Morse 1980), which is the type site for the Big Lake phase. Similar components have been recently

Installation Restoration Program, Phase 2. Confirmation/Quantification, Stage 1. Kalispell Air Force Station, Montana

DTIC Science & Technology

1989-05-01

AFB Statement of Work. The Phase II Stage 1 investigation of Malmstrom AFB and two off-Base sites at Shelby and Brady, Montana are described in a...Flathead National Forest Headquarters in Kalispell and the Big Fork Ranger Station in Big Fork . Because there has been litigation involved with this...reviewed by phone. An interview at the spill site was held with Mr. William Pedersen, U.S. Forest Service Ranger for the Big Fork District. He personally

Stem Cells in the Trabecular Meshwork for Regulating Intraocular Pressure.

PubMed

Yun, Hongmin; Zhou, Yi; Wills, Andrew; Du, Yiqin

2016-06-01

Intraocular pressure (IOP) is still the main treatment target for glaucoma. Outflow resistance mainly exists at the trabecular meshwork (TM) outflow pathway, which is responsible for IOP regulation. Changes of TM cellularity and TM extracellular matrix turnover may play important roles in IOP regulation. In this article, we review basic anatomy and physiology of the outflow pathway and TM stem cell characteristics regarding the location, isolation, identification and function. TM stem cells are localized at the insert region of the TM and are label-retaining in vivo. They can be isolated by side-population cell sorting, cloning culture, or sphere culture. TM stem cells are multipotent with the ability to home to the TM region and differentiate into TM cells in vivo. Other stem cell types, such as adipose-derived stem cells, mesenchymal stem cells and induced pluripotent stem cells have been discovered for TM cell differentiation and TM regeneration. We also review glaucomatous animal models, which are suitable to study stem cell-based therapies for TM regeneration.

Stem Cells in the Trabecular Meshwork for Regulating Intraocular Pressure

PubMed Central

Yun, Hongmin; Zhou, Yi; Wills, Andrew

2016-01-01

Abstract Intraocular pressure (IOP) is still the main treatment target for glaucoma. Outflow resistance mainly exists at the trabecular meshwork (TM) outflow pathway, which is responsible for IOP regulation. Changes of TM cellularity and TM extracellular matrix turnover may play important roles in IOP regulation. In this article, we review basic anatomy and physiology of the outflow pathway and TM stem cell characteristics regarding the location, isolation, identification and function. TM stem cells are localized at the insert region of the TM and are label-retaining in vivo. They can be isolated by side-population cell sorting, cloning culture, or sphere culture. TM stem cells are multipotent with the ability to home to the TM region and differentiate into TM cells in vivo. Other stem cell types, such as adipose-derived stem cells, mesenchymal stem cells and induced pluripotent stem cells have been discovered for TM cell differentiation and TM regeneration. We also review glaucomatous animal models, which are suitable to study stem cell-based therapies for TM regeneration. PMID:27183473

Influence of Grape Seeds and Stems on Wine Composition and Astringency.

PubMed

Pascual, Olga; González-Royo, Elena; Gil, Mariona; Gómez-Alonso, Sergio; García-Romero, Esteban; Canals, Joan Miquel; Hermosín-Gutíerrez, Isidro; Zamora, Fernando

2016-08-31

The aim of this paper is to study the real influence of seeds and stems on wine composition, astringency, and bitterness. A decolored grape juice and a grape juice macerated for 4 days from the same Cabernet Sauvignon grapes were fermented with or without supplementation with 100% seeds, 300% seeds, or 100% stems. Once alcoholic fermentation had finished, the wines were analyzed and tasted. The presence of seeds and stems increased the concentration of flavan-3-ol monomers with respect to the controls. However, the seeds mainly released (+)-catechin and (-)-epicatechin, whereas the stems mainly released (+)-catechin and (+)-gallocatechin. The seeds and stems also released proanthocyanidins; those from seeds have a lower mDP and a high percentage of galloylation, whereas those from stems have a higher mDP and a relatively high percentage of prodelphinidins. The presence of seeds and stems brought about a slight but significant increase in pH and lowered titratable acidity and ethanol content. The presence of seeds boosted color intensity, whereas stems had the opposite effect. Finally, both seeds and stems increased wine astringency and bitterness.

The depositional web on the floodplain of the Fly River, Papua New Guinea

NASA Astrophysics Data System (ADS)

Day, Geoff; Dietrich, William E.; Rowland, Joel C.; Marshall, Andrew

2008-03-01

Floodplain deposition on lowland meandering rivers is usually interpreted as either lateral accretion during channel migration or overbank deposition. Previous studies on the Fly River in Papua New Guinea suggest, however, that floodplain channels (consisting of tie channel and tributary channels) play an important role in conveying sediment out across the floodplain. Here we report the results of an intensive field study conducted from 1990 to 1998 that documents the discharge of main stem water from the Fly River onto its floodplain and maps the spatial pattern of sediment deposition on the floodplain (using as a tracer elevated particulate copper introduced into the system by upstream mining). An extensive network of water level recorders demonstrates significant hydraulic heads from the main stem out the floodplain channels. For the monitoring period 1995-1998, net water discharge into the floodplain channels was about 20% of the flow. Another 20% is estimated to spill overbank from the main stem in wet years. Annual floodplain coring from 1990 to 1994 obtained over 800 samples across the 3500 km2 Middle Fly floodplain for use in documenting temporal and spatial patterns of sediment deposition. Early samples record the rapid spread of sediment up to 10 km away from the main stem via floodplain channels. Later, more intensive coring samples documented a well-defined exponential decline in sediment deposition from the nearest channel (which differed little between floodplain and main stem channels). Deposition, averaging about 6-9 mm/a, occurred in a 1 km corridor either side of these channels and effectively ceased beyond that distance. About 40% of the total sediment load was deposited on the floodplain, with half of that being conveyed by the over 900 km of floodplain channels (equal to about 0.09% sediment deposition/km of main stem channel length). Levee topographies along the main stem and floodplain channels are similar but cannot be explained by the observed exponential functions. Channel margin shear flow during extended periods of flooding may give rise to the localized levee deposition. Our study demonstrates that tie and tributary floodplain channels can inject large volumes of sediment-laden main stem waters great distances across the floodplain where they spill overbank, forming a narrow band of deposition, thereby creating a depositional web.

Patients' Main Concerns About Having a Sibling Stem Cell Donor - A Grounded Theory Study.

PubMed

Kisch, Annika M; Forsberg, Anna

2018-01-01

There is limited knowledge about the perspective of patients undergoing allogeneic haematopoietic stem cell transplantation (HSCT) about having a sibling as donor. It is essential to understand the main concerns of stem cell recipients in order to enable nurses to provide person-centred care. The study aim was to explore patients' main concerns about having a sibling stem cell donor and how the patients handle them, from immediately before until one year after transplantation. Twenty-eight interviews were performed prospectively during one year with ten adult sibling stem cell recipients with a mean age of 52 years (range 19-68 years). The interviews were analyzed by the Grounded Theory method. The core category Recompensation summarises the process in the generated grounded theory including the three main categories; Invest , Compensate and Celebrate . Recompensation is defined as a lasting compensation given by the recipient to the sibling donor for the loss or harm suffered or effort made. The sense of having to reward, protect, appreciate, maintain peace and work on the relationship with the sibling donor at the same time as having to accept a serious illness, cope with their situation and promote their own recovery is strenuous for the recipients. The main concern for stem cell recipients during their first post-transplant year is to recompensate the sibling donor by investing, compensating and celebrating her/him. Although there is a positive aspect of recompensation, it can also imply pressure and guilt.

Electrochemical growth of controlled tip shapes of ZnO nanorod arrays on silicon substrate and enhanced photoluminescence emission from nanopyramid arrays compared with flat-head nanorods

NASA Astrophysics Data System (ADS)

Alimanesh, Mahmoud; Hassan, Z.; Zainal, Norzaini

2017-10-01

Zinc oxide (ZnO) nanorod arrays (NRAs) with different morphologies such as; perfect hexagon flat-head, pyramidal, compact pencil, nail-shaped, and high-compact ZnO nanorod thin films, were successfully grown on silicon substrates. These NRAs were formed on substrates using a simple low-temperature electrochemical method without adding any catalyst or template via the precursors of zinc nitrate hexahydrate [Zn(NO3)2·6H2O] and hexamethylenetetramine [HMT; C6H12N4] with an equal molar concentration of 0.025 mol/l. The morphologies of the ZnO nanorods (NRs) could be controlled and transformed successfully in to other morphologies by changing the growth conditions, such as; growth temperature and applied current density. Detailed structural investigations reveal that the synthesized various NRs are single crystalline with wurtzite hexagonal phase and preferentially grow along the c-axis direction. The room temperature photoluminescence spectra show that each spectrum consists of an ultraviolet (UV) band and a relative broad visible light emission and infrared emission peak. The enhanced light emission intensity at UV peak (∼375 nm) is observed significantly from ZnO nanopyramid (NP) arrays because of the conical shape of NP. The photoluminescence intensity of the UV peak from the NPs is found to be 1.5-17 times larger than those from the other various NRs.

Examining Suitable Soil Regimes for Reestablishment of Camassia Quamash (Blue Camas), Flathead Indian Reservation

NASA Astrophysics Data System (ADS)

Bald, A. M.; Davis, J. M.

2014-12-01

Soils are the foundation of all biotic communities and play a substantial role in facilitating the uptake of water and nutrients in many terrestrial plants. Plants can grow to their potential only if the soil supports an environment conducive to growth. Soil chemical composition and texture directly influence the rate of water and nutrient ion uptake in vegetation. Prairie Wetlands have experienced the most dramatic land use changes within the United States throughout the last century. Soils deteriorate from erosion, compaction, use of pesticides, herbicides, and fertilizers associated with agriculture and urbanization. Transitioning soil regimes in the US have been the impetus for numerous restoration activities that attempt to protect or remediate loss to native or functional plant groups. Success of plant restoration efforts is dependent on knowledge about regional soil regimes. Camassia Quamash (Blue Camas), an ephemeral wetland bulbaceous herb is a culturally significant edible plant to the Pacific Northwest tribes and was only surpassed as a subsistence trade commodity by Salmon. The literature about camas and suitable soil types for it to grow is limited. The Confederated Salish and Kootenai Tribes interest in restoring the plant to the Flathead Indian Reservation (FIR) prompted a series of research initiatives to document baseline parameters of remaining camas stands. Baseline soil conditions examining chemical regimes and soil textures on four FIR observed camas sites were analyzed. Samples indicated that remaining camas stands occurred in loamy nutrient rich prairie wetland to lightly forested soil regimes.

Ecological assessment of streams in the Powder River Structural Basin, Wyoming and Montana, 2005-06

USGS Publications Warehouse

Peterson, D.A.; Wright, P.R.; Edwards, G.P.; Hargett, E.G.; Feldman, D.L.; Zumberge, J.R.; Dey, Paul

2009-01-01

Energy and mineral development, particularly coalbed natural gas development, is proceeding at a rapid pace in the Powder River Structural Basin (PRB) in northeastern Wyoming. Concerns about the potential effects of development led to formation of an interagency working group of primarily Federal and State agencies to address these issues in the PRB in Wyoming and in Montana where similar types of resources exist but are largely undeveloped. Under the direction of the interagency working group, an ecological assessment of streams in the PRB was initiated to determine the current status (2005–06) and to establish a baseline for future monitoring.The ecological assessment components include assessment of stream habitat and riparian zones as well as assessments of macroinvertebrate, algal, and fish communities. All of the components were sampled at 47 sites in the PRB during 2005. A reduced set of components, consisting primarily of macroinvertebrate and fish community assessments, was sampled in 2006. Related ecological data, such as habitat and fish community data collected from selected sites in 2004, also are included in this report.The stream habitat assessment included measurement of channel features, substrate size and embeddedness, riparian vegetation, and reachwide characteristics. The width-to-depth ratio (bankfull width/bankfull depth) tended to be higher at sites on the main-stem Powder River than at sites on the main-stem Tongue River and at sites on tributary streams. The streambed substrate particle size was largest at sites on the main-stem Tongue River and smallest at sites on small tributary streams such as Squirrel Creek and Otter Creek. Total vegetative cover at the ground level, understory, and canopy layers ranged from less than 40 percent at a few sites to more than 90 percent at many of the sites. A bank-stability index indicated that sites in the Tongue River drainage were less at risk of bank failure than sites on the main-stem Powder River.Macroinvertebrate communities showed similarity at the river-drainage scale. Macroinvertebrate communities at sites with mountainous headwaters and snowmelt-driven hydrology, such as Clear Creek, Crazy Woman Creek, and Goose Creek, showed similarity with communities from the main-stem Tongue River. The data also indicated similarity among sites on the main-stem Powder River and among small tributaries of the Tongue River. Data analyses using macroinvertebrate observed/expected models and multimetric indices developed by the States of Wyoming and Montana indicated a tendency toward declining biological condition in the downstream direction along the Tongue River. Biological condition for the main-stem Powder River generally improved downstream, from below Salt Creek to near the Wyoming/Montana border, followed by a general decline downstream from the border to the confluence with the Yellowstone River. The biological condition generally was not significantly different between 2005 and 2006, although streamflow was less in 2006 because of drought.Algal communities showed similarity at the river-drainage scale with slight differences from the pattern observed in the macroinvertebrate communities. Although the algal communities from Clear Creek and Goose Creek were similar to those from the main-stem Tongue River, as was true of the macroinvertebrate communities, the algal communities from Crazy Woman Creek had more similarity to those of main-stem Powder River sites than to the Tongue River sites, contrary to the macroinvertebrates. Ordination of algal communities, as well as diatom metrics including salinity and dominant taxa, indicated substantial variation at two sites along the main stem of the Powder River.Fish communities of the PRB were most diverse in the Tongue River drainage. In part due to the effects of Tongue River Reservoir, 15 species of fish were found in the Tongue River drainage that were not found in the Cheyenne, Belle Fourche, or Little Powder River drainages. The number of introduced species and relative abundance of introduced species of fish were higher in the Tongue River and other drainages than at sites on the main-stem Powder River. Although non-native species were identified in the Powder River, the native fish community is largely intact. Western silvery minnow and sturgeon chub—species of special concern—were identified only at sites on the main-stem Powder River and were most common in the Montana segment of the main stem. Fish and habitat sampling on the main-stem Powder River indicated affinity of some species for certain habitats such as pools, runs, riffles, backwaters, or shoals.

Montana Valley and Foothill Prairies Ecoregion: Chapter 6 in Status and trends of land change in the Western United States--1973 to 2000

USGS Publications Warehouse

Taylor, Janis L.

2012-01-01

The Montana Valley and Foothill Prairies Ecoregion comprises numerous intermountain valleys and low-elevation foothill prairies spread across the western half of Montana, on both sides of the Continental Divide (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The ecoregion, which covers approximately 64,658 km2 (24,965 mi2), includes the Flathead Valley and the valleys surrounding Helena, Missoula, Bozeman, Billings, Anaconda, Dillon, and Lewistown (fig. 1). These valleys are generally characterized by shortgrass prairie vegetation and are flanked by forested mountains (Woods and others, 1999); thus, the valleys’ biotas with regards to fish and insects are comparable. In many cases, the valleys are conduits for some of the largest rivers in the state, including Clark Fork and the Missouri, Jefferson, Madison, Flathead, Yellowstone, Gallatin, Smith, Big Hole, Bitterroot, and Blackfoot Rivers (fig. 2). The Montana Valley and Foothill Prairies Ecoregion also includes the “Rocky Mountain front,” an area of prairies along the eastern slope of the northern Rocky Mountains. Principal land uses within the ecoregion include farming, grazing, and mining. The valleys serve as major transportation and utility corridors and also contain the majority of Montana’s human population. The Montana Valley and Foothill Prairies Ecoregion extends into 17 mostly rural counties throughout western Montana. Only three of the counties—Carbon, Yellowstone, and Missoula—are part of a metropolitan statistical area with contiguous built-up areas tied to an employment center. Nearly two-thirds of Montana residents live in nonmetropolitan counties (Albrecht, 2008). Ten of the counties within the ecoregion had population growth rates greater than national averages (9–13 percent) between 1970 and 2000 (table 1). Ravalli and Gallatin Counties had the highest growth rates. Population growth was largely due to amenity-related inmigration and an economy dependent on tourism, health care, and services. Counties that had population declines, such as Deer Lodge, Silver Bow, and Meagher Counties, also had declines in agriculture and mining activity, and they had railroad closures as well. Climate varies from north to south and from the east side of the Continental Divide to the west side. However, all areas are semiarid with long cold winters and short growing seasons. In the western part of the ecoregion, Beaverhead, Bitterroot, Flathead, and Lolo National Forests provide the natural resources, particularly timber, that form the economic base for towns within nearby valleys. Mineral resources from mines in and around Anaconda, Deer Lodge, and Butte have long provided an economic base for these towns (fig. 3).

Investigation of the profile of phenolic compounds in the leaves and stems of Pandiaka heudelotii using gas chromatography coupled with flame ionization detector.

PubMed

Ifeanacho, Mercy O; Ikewuchi, Catherine C; Ikewuchi, Jude C

2017-05-01

The profile of phenolic compounds in the leaves and stems of Pandiaka heudelotii was investigated using gas chromatography coupled with flame ionization detector. The leaves and stems had high flavonoids and benzoic acid derivatives content, and moderate levels of lignans and hydroxycinnamates. Twenty-eight known flavonoids were detected, which consisted mainly of kaempferol (41.93% in leaves and 47.97% in stems), (+)-catechin (17.12% in leaves and 16.11% in stems), quercetin (13.83% in leaves and 9.39% in stems), luteolin (7.34% in leaves and 7.71% in stems), and artemetin (6.53% in leaves and 4.83% in stems). Of the six known hydroxycinnamates detected, chlorogenic acid (80.79% in leaves and 87.56% in stems) and caffeic acid (18.98% in leaves and 12.30% in stems) were the most abundant, while arctigenin (77.81% in leaves and 83.40% in stems) and retusin (13.82% in leaves and 10.59% in stems) were the most abundant of the nine known lignans detected. Twelve known benzoic acid derivatives were detected, consisting mainly of ellagic acid (65.44% in leaves and 72.89% in stems), p-hydroxybenzoic acid (25.10% in leaves and 18.95% in stems), and vanillic acid (8.80% in leaves and 7.30% in stems). The rich phytochemical profile of the leaves and stems is an indication of their ability to serve as sources of nutraceuticals.

Stem Cell Therapy in Bladder Dysfunction: Where Are We? And Where Do We Have to Go?

PubMed Central

Lee, Sang-Rae; Song, Yun Seob; Lee, Hong Jun

2013-01-01

To date, stem cell therapy for the bladder has been conducted mainly on an experimental basis in the areas of bladder dysfunction. The therapeutic efficacy of stem cells was originally thought to be derived from their ability to differentiate into various cell types. Studies about stem cell therapy for bladder dysfunction have been limited to an experimental basis and have been less focused than bladder regeneration. Bladder dysfunction was listed in MESH as “urinary bladder neck obstruction”, “urinary bladder, overactive”, and “urinary bladder, neurogenic”. Using those keywords, several articles were searched and studied. The bladder dysfunction model includes bladder outlet obstruction, cryoinjured, diabetes, ischemia, and spinal cord injury. Adipose derived stem cells (ADSCs), bone marrow stem cells (BMSCs), and skeletal muscle derived stem cells (SkMSCs) are used for transplantation to treat bladder dysfunction. The main mechanisms of stem cells to reconstitute or restore bladder dysfunction are migration, differentiation, and paracrine effects. The aim of this study is to review the stem cell therapy for bladder dysfunction and to provide the status of stem cell therapy for bladder dysfunction. PMID:24151627

The fishermen were right: experimental evidence for tributary refuge hypothesis during floods.

PubMed

Koizumi, Itsuro; Kanazawa, Yukiyo; Tanaka, Yuuki

2013-05-01

Fishermen often anecdotally report an unexpected increase of fish caught in small tributary streams during floods, presumably due to refuge-seeking behavior from the main stem. From a population perspective, this implies the significance of refuge habitats and connectivity for population viability against natural disturbances. Despite the plausibility, however, surprisingly few studies have examined the tributary refuge hypothesis, mainly due to the difficulty in field survey during floods. Here, we made use of a large-scale controlled flood to assess whether fishes move into tributaries during flooding in the main stem. A planned water release from the Satsunai River Dam located on Hokkaido Island in Japan rapidly increased the main stem discharge by more than 20-fold. Before, during, and after flooding censuses in four tributaries provided evidence of the refuge-seeking behavior of fishes from the main stem. For example, more than 10 Dolly Varden char, a salmonid fish, were caught in a tributary during the flood, even though almost no individuals were captured before or after the flood. The fish responded immediately to the flooding, suggesting the need for studies during disturbances. In addition, the likelihood of refuge movements varied among tributaries, suggesting the importance of local environmental differences between tributary and the main stem habitats. This is the first study to experimentally confirm the tributary refuge hypothesis, and underscores the roles of habitat diversity and connectivity during disturbances, even though some habitats are not used during normal conditions.

Puget Sound Dredged Disposal Analysis (PSDDA). Final Environmental Impact Statement Unconfined Open-Water Disposal for Dredged Material, Phase 2. (North and South Puget Sound)

DTIC Science & Technology

1989-09-01

flathead sole, rex sole, and rock sole all showed indications of blood worm infestations. One liver tumor was found in a rex sole during spring in the ZSF...concentrations Hainly in invertebrates; some trations (.01 ppb) in waters (from lOx to 42Ox reference) in fish livers ; rarely in fish of Puget Sound central...Eagle Harbor, and Sinclair fish livers , and birds in Inlet. Highest elevation industrialized ’-ban areas. along Ruston-Point Defiance Copper is a natural

A New Saurolophine Dinosaur from the Latest Cretaceous of Far Eastern Russia

PubMed Central

Godefroit, Pascal; Bolotsky, Yuri L.; Lauters, Pascaline

2012-01-01

Background Four main dinosaur sites have been investigated in latest Cretaceous deposits from the Amur/Heilongjiang Region: Jiayin and Wulaga in China (Yuliangze Formation), Blagoveschensk and Kundur in Russia (Udurchukan Formation). More than 90% of the bones discovered in these localities belong to hollow-crested lambeosaurine saurolophids, but flat-headed saurolophines are also represented: Kerberosaurus manakini at Blagoveschensk and Wulagasaurus dongi at Wulaga. Methodology/Principal Findings Herein we describe a new saurolophine dinosaur, Kundurosaurus nagornyi gen. et sp. nov., from the Udurchukan Formation (Maastrichtian) of Kundur, represented by disarticulated cranial and postcranial material. This new taxon is diagnosed by four autapomorphies. Conclusions/Significance A phylogenetic analysis of saurolophines indicates that Kundurosaurus nagornyi is nested within a rather robust clade including Edmontosaurus spp., Saurolophus spp., and Prosaurolophus maximus, possibly as a sister-taxon for Kerberosaurus manakini also from the Udurchukan Formation of Far Eastern Russia. The high diversity and mosaic distribution of Maastrichtian hadrosaurid faunas in the Amur-Heilongjiang region are the result of a complex palaeogeographical history and imply that many independent hadrosaurid lineages dispersed without any problem between western America and eastern Asia at the end of the Cretaceous. PMID:22666331

Nutrient-Chlorophyll Relationships in the Indian River Lagoon, Florida

EPA Science Inventory

The Indian River Lagoon is a highly diverse estuary located along Florida’s Atlantic coast. The system is made up of the main stem and two side-lagoons: the Banana River and Mosquito Lagoon. We segmented the main stem into three sections based on spatial trends in water quality ...

Nutrient-Chlorophyll Relationships in the Indian River Lagoon, Florida(SEERS)

EPA Science Inventory

The Indian River Lagoon is a highly diverse estuary located along Florida’s Atlantic coast. The system is made up of the main stem and two side-lagoons: the Banana River and Mosquito Lagoon. We segmented the main stem into three sections based on spatial trends in water quality ...

[Progress in stem cells and regenerative medicine].

PubMed

Wang, Libin; Zhu, He; Hao, Jie; Zhou, Qi

2015-06-01

Stem cells have the ability to differentiate into all types of cells in the body and therefore have great application potential in regenerative medicine, in vitro disease modelling and drug screening. In recent years, stem cell technology has made great progress, and induced pluripotent stem cell technology revolutionizes the whole stem cell field. At the same time, stem cell research in our country has also achieved great progress and becomes an indispensable power in the worldwide stem cell research field. This review mainly focuses on the research progress in stem cells and regenerative medicine in our country since the advent of induced pluripotent stem cell technology, including induced pluripotent stem cells, transdifferentiation, haploid stem cells, and new gene editing tools.

[Genetic regulation of plant shoot stem cells].

PubMed

Al'bert, E V; Ezhova, T A

2013-02-01

This article describes the main features of plant stem cells and summarizes the results of studies of the genetic control of stem cell maintenance in the apical meristem of the shoot. It is demonstrated that the WUS-CLV gene system plays a key role in the maintenance of shoot apical stem cells and the formation of adventitious buds and somatic embryos. Unconventional concepts of plant stem cells are considered.

The stem cell patent landscape as relevant to cancer vaccines.

PubMed

Wang, Shyh-Jen

2011-10-01

Cancer vaccine targeting cancer stem cells is proposed to serve as a potent immunotherapy. Thus, it would be useful to examine the main trends in stem cell patenting activity as a guide for those seeking to develop such cancer vaccines. We found that a substantial number of stem cell patents were granted up to the end of 2010, including ~2000 issued in the US. Many of these have been filed since 2001, including 7,551 applications in the US. Stem cell development, as evidenced by the numbers of PubMed articles, has matured steadily in recent years. However, the other metrics, such as the number of patent applications, the technology-science linkage and the number of patent assignees, have been stagnant. Moreover, the ownership of stem cell patents is still quiet fragmented across multiple organizations, and the number of stem cell patent assignees from the business sector has not increased significantly. Academic and nonprofit institutions not only account for a large share of stem cell patents but also apply for patents continually. Based on this analysis, the strength of stem cell resources seems to remain stagnant in recent years due to the ban on government funding of embryonic stem cell research. Furthermore, the patent prosecution or technical barriers in the field of stem cells would be another main reason that the number of US-issued stem cell patents for each application have been in gradual decline since 2000. Therefore, we consider stem cell technology to still be under development.

Vulnerability of age-0 pallid sturgeon Scaphirhynchus albus to predation; effects of predator type, turbidity, body size, and prey density

USGS Publications Warehouse

French, William E.; Graeb, Brian D. S.; Chipps, Steven R.; Klumb, Robert A.

2014-01-01

Predation can play an important role in the recruitment dynamics of fishes with intensity regulated by behavioral (i.e., prey selectivity) and/or environmental conditions that may be especially important for rare or endangered fishes. We conducted laboratory experiments to quantify prey selection and capture efficiency by three predators employing distinct foraging strategies: pelagic piscivore (walleye Sander vitreus); benthic piscivore (flathead catfish Pylodictis olivaris) and generalist predator (smallmouth bass Micropterus dolomieu) foraging on two size classes of age-0 pallid sturgeon: large (75–100 mm fork length [FL]) and small (40–50 mm FL). Experiments at high (> 70 nephalometric turbidity units [NTU]) and low (< 5 NTU) turbidity for each predator were conducted with high and low densities of pallid sturgeon and contrasting densities of an alternative prey, fathead minnow Pimephales promelas. Predator behaviors (strikes, captures, and consumed prey) were also quantified for each prey type. Walleye and smallmouth bass negatively selected pallid sturgeon (Chesson’s α = 0.04–0.1) across all treatments, indicating low relative vulnerability to predation. Relative vulnerability to predation by flathead catfish was moderate for small pallid sturgeon (α = 0.44, neutral selection), but low for large pallid sturgeon (α = 0.11, negative selection). Turbidity (up to 100 NTU) did not affect pallid sturgeon vulnerability, even at low density of alternative prey. Age-0 pallid sturgeon were easily captured by all predators, but were rarely consumed, suggesting mechanisms other than predator capture efficiency govern sturgeon predation vulnerability.

Estimating thermal regimes of bull trout and assessing the potential effects of climate warming on critical habitats

USGS Publications Warehouse

Jones, Leslie A.; Muhlfeld, Clint C.; Marshall, Lucy A.; McGlynn, Brian L.; Kershner, Jeffrey L.

2013-01-01

Understanding the vulnerability of aquatic species and habitats under climate change is critical for conservation and management of freshwater systems. Climate warming is predicted to increase water temperatures in freshwater ecosystems worldwide, yet few studies have developed spatially explicit modelling tools for understanding the potential impacts. We parameterized a nonspatial model, a spatial flow-routed model, and a spatial hierarchical model to predict August stream temperatures (22-m resolution) throughout the Flathead River Basin, USA and Canada. Model comparisons showed that the spatial models performed significantly better than the nonspatial model, explaining the spatial autocorrelation found between sites. The spatial hierarchical model explained 82% of the variation in summer mean (August) stream temperatures and was used to estimate thermal regimes for threatened bull trout (Salvelinus confluentus) habitats, one of the most thermally sensitive coldwater species in western North America. The model estimated summer thermal regimes of spawning and rearing habitats at <13 C° and foraging, migrating, and overwintering habitats at <14 C°. To illustrate the useful application of such a model, we simulated climate warming scenarios to quantify potential loss of critical habitats under forecasted climatic conditions. As air and water temperatures continue to increase, our model simulations show that lower portions of the Flathead River Basin drainage (foraging, migrating, and overwintering habitat) may become thermally unsuitable and headwater streams (spawning and rearing) may become isolated because of increasing thermal fragmentation during summer. Model results can be used to focus conservation and management efforts on populations of concern, by identifying critical habitats and assessing thermal changes at a local scale.

Updated analysis of flatfish recruitment response to climate variability and ocean conditions in the Eastern Bering Sea

NASA Astrophysics Data System (ADS)

Wilderbuer, Thomas; Stockhausen, William; Bond, Nicholas

2013-10-01

This study provides a retrospective analysis of the relationship between physical oceanography, biology and recruitment of three Eastern Bering Sea flatfish stocks: flathead sole (Hippoglossoides elassodon), northern rock sole (Lepidopsetta polyxystra), and arrowtooth flounder (Atheresthes stomias) during the period 1978-2005. Stock assessment model estimates of recruitment and spawning stock size indicate that temporal patterns in productivity are consistent with decadal scale (or shorter) patterns in climate variability, which may influence marine survival during the early life history phases. Density-dependence (through spawning stock size) was statistically significant in a Ricker stock-recruit model of flatfish recruitment that included environmental terms. Wind-driven advection of northern rock sole and flathead sole larvae to favorable nursery grounds was found to coincide with years of above-average recruitment. Ocean forcing of Bristol Bay surface waters during springtime was mostly on-shelf (eastward) during the 1980s and again in the early 2000s, but was off-shelf (westerly) during the 1990s, corresponding with periods of good and poor recruitment, respectively. Finally, the Arctic Oscillation was found to be an important indicator of arrowtooth flounder productivity. Model results were applied to IPCC (Intergovernmental Panel on Climate Change) future springtime wind scenarios to predict the future impact of climate on northern rock sole productivity and indicated that a moderate future increase in recruitment might be expected because the climate trends favor on-shelf transport but that density-dependence will dampen this effect such that northern rock sole abundance will not be substantially affected by climate change.

Effects of Salinity on the Habitat Selection and Growth Performance of Mediterranean Flathead Grey Mullet Mugil cephalus (Osteichthyes, Mugilidae)

NASA Astrophysics Data System (ADS)

Cardona, L.

2000-05-01

Flathead grey mullet (Mugil cephalus L. 1758) are commonly found in tropical and temperate estuaries. In spite of their ecological and economical importance, little is known about the effects of salinity on growth performance and habitat selection. Laboratory experiments revealed that the metabolic rate of young specimens was negatively affected by high salinity levels and that an improved growth performance was achieved in fresh water and oligohaline water. A stratified study on microhabitat use, carried out on the island of Minorca (Balearic archipelago), demonstrated that juvenile specimens, shorter than 200 mm (total length), concentrated all year round in fresh water or oligohaline sites. Mesohaline areas were usually avoided, except in summer. Immature fish, with a total length between 201 and 300 mm, show a similar pattern although in some seasons avoided freshwater sites. The habitat selection pattern of adults, i.e., fish longer than 301 mm, changed seasonally due to their offshore migration during the spawning season (from late summer to early winter). However, they usually showed a greater preference for polyhaline areas and strongly avoided freshwater sites. Euhaline areas were also avoided in autumn and summer. These results suggest that the young of this species are highly dependent on areas of low salinity and any factor which reduces the availability of such areas will, in turn, affect their fishery. Adults depend on polyhaline areas, although the avoidance of freshwater areas might be due to their shallowness. The situation might be different in some areas of the Indo-Pacific. These differences are discussed.

Metal levels in flathead sole (Hippoglossoides elassodon) and great sculpin (Myoxocephalus polyacanthocephalus) from Adak Island, Alaska: Potential risk to predators and fishermen

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burger, Joanna; Gochfeld, Michael; Environmental and Occupational Medicine, UMDNJ-Robert Wood Johnson Medical School, Piscataway, NJ 08854

2007-01-15

Increasingly there is a need to assess the contaminant levels in fish as indicators of the health and well-being of both the fish and their consumers, including humans. This paper examines the levels of arsenic, cadmium, chromium, lead, manganese, mercury, and selenium in the kidney, liver, and muscle of great sculpin and flathead sole from Adak Island in the Aleutian Islands, Alaska. Both species are consumed by the local Aleuts and others. There were significant differences in the levels of heavy metals as a function of tissue for both fish species; the liver of sculpin and sole generally had themore » highest levels of most metals, except for arsenic, lead, and selenium. Sole had significantly higher mean levels of arsenic in kidney (32,384 vs. 531 ppb, wet weight), liver (18,954 vs. 2532 ppb), and muscle (19,452 vs. 1343 ppb) than did sculpin. Sole also had higher mean levels of cadmium (230 vs. 63 ppb), lead (1236 vs. 48 ppb), mercury (150 vs. 107 ppb), and selenium (5215 vs. 1861 ppb) in kidney than did sculpin. There were significant correlations among weight and length measurements for both species. However, except for mercury, there were few significant correlations among tissue types for most metals. Only mercury and manganese levels were significantly correlated with size for sculpin (but not for sole). Levels of arsenic, lead, and mercury may pose a risk to predators that consume them, and arsenic and mercury may pose a risk to human consumers.« less

Push-To-Lock, Push-To-Release Mechanism

NASA Technical Reports Server (NTRS)

Lozano, Anselmo, Jr.

1991-01-01

Latch locked or unlocked with single motion of hand. No tools needed to operate it, and user easily opens or closes it with heavily gloved hand. When unlocked, stem free of main body. In locked state, dowel pins in main body hold stem. Latch equipped with lock and key so only authorized users operate it.

Index of surface-water stations in Texas, January 1984

USGS Publications Warehouse

Carrillo, E.R.; Buckner, H.D.

1984-01-01

This index shows the station number and name, latitude and longitude, type of data collected, and the office principally responsible for the data collection (table 1). An 8-digit permanent numerical designation for gaging stations has been adopted on a nationwide basis; stations are numbered and listed in downstream order. In the downstream direction along the main stem, all stations on a tributary entering above a main-stem station are listed before that station. A tributary entering between two main-stem stations is listed between them. A similar order is followed in listing stations on first rank, second rank, and other ranks of tributaries. To indicate the rank of any tributary on which a gaging station is situated and the stream to which it is an immediate tributary, each indention in the listing of gaging stations represent one rank. This downstream order and system of indention show which gaging stations are on tributaries between any two stations on a main stem and the rank of the tributary on which each gaging station is situated. On plates 1 and 2 the 8-digit station number is abbreviated because of space limitation.

Index of surface-water stations in Texas, January 1985

USGS Publications Warehouse

Carrillo, E.R.; Buckner, H.D.; Rawson, Jack

1984-01-01

This index shows the station number -and name, latitude and longitude, type of data collected, and the office principally responsible for the data collection (table 1). An 8-digit permanent numerical designation for gaging stations has been adopted on a nationwide basis; stations are numbered and listed in downstream order. In the downstream direction along the main stem, all stations on a tributary entering above a main-stem station are listed before that station. A tributary entering between two main-stem stations is listed between them. A similar order is followed in listing stations on first rank, second rank, and other ranks of tributaries. To indicate the rank of any tributary on which a gaging station is situated and the stream to which it is an immediate tributary, each indention in the listing of gaging stations represent one rank. This downstream order and system of indention show which gaging stations are on tributaries between any two stations on a main stem and the rank of the tributary on which each gaging station is situated. On plates 1 and 2, the 8-digit station number is abbreviated because of space limitation.

Index of surface-water stations in Texas, January 1987

USGS Publications Warehouse

Rawson, Jack; Carrillo, E.R.; Buckner, H.D.

1987-01-01

This index shows the station number and name, latitude and longitude, type of data collected, and the office principally responsible for the data collection (table 1). An 8-digit permanent numerical designation for gaging stations has been adopted on a nationwide basis; stations are numbered and listed in downstream order. In the downstream direction along the main stem, all stations on a tributary entering above a main-stem station are listed before that station. A tributary entering between two main-stem stations is listed between them. A similar order is followed in listing stations on first rank, second rank, and other ranks of tributaries. To indicate the rank of any tributary on which a gaging station is situated and the stream to which it is an immediate tributary, each indention in the listing of gaging stations represent one rank. This downstream order and system of indention show which gaging stations are on tributaries between any two stations on a main stem and the rank of the tributary on which each gaging station is situated. On plates 1 and 2, the 8-digit station number is abbreviated because of space limitation.

Index of surface-water stations in Texas, January 1988

USGS Publications Warehouse

Rawson, Jack; Carrillo, E.R.; Buckner, H.D.

1988-01-01

This index shows the station number and name, latitude and longitude, type of data collected, and the office principally responsible for the data collection (table 1). An 8-digit permanent numerical designation for gaging stations has been adopted on a nationwide basis; stations are numbered and listed in downstream order. In the downstream direction along the main stem, all stations on a tributary entering above a main-stem station are listed before that station. A tributary entering between two main-stem stations is listed between them. A similar order is followed in listing stations on first rank, second rank, and other ranks of tributaries. To indicate the rank of any tributary on which a gaging station is situated and the stream to which it is an immediate tributary, each indention in the listing of gaging stations represent one rank. This downstream order and system of indention show which gaging stations are on tributaries between any two stations on a main stem and the rank of the tributary on which each gaging station is situated. On plates 1 and 2, the 8-digit station number is abbreviated because of space limitation.

[Open-top Chamber for in situ Research on Response of Mercury Enrichment in Rice to the Rising Gaseous Elemental Mercury in the Atmosphere].

PubMed

Chen, Jian; Wang, Zhang-wei; Zhang, Xiao-shan; Qin, Pu-feng; Lu, Hai-jun

2015-08-01

In situ research was conducted on the response of mercury enrichment in rice organs to elevated gaseous elemental mercury (GEM) with open-top chambers (OTCs) fumigation experiment and soil Hg enriched experiment. The results showed that Hg concentrations in roots were generally correlated with soil Hg concentrations (R = 0.9988, P < 0.05) but insignificantly correlated with air Hg concentrations (P > 0.05), indicating that Hg in rice roots was mainly from soil. Hg concentrations in stems increased linearly (R(B) = 0.9646, R(U) = 0.9831, P < 0.05) with elevated GEM, and Hg concentrations in upper stems were usually higher than those in bottom stems in OTCs experiment. Hg concentrations in bottom stems were generally correlated with soil Hg concentrations (R = 0.9901, P < 0.05) and second-order polynomial (R = 0.9989, P < 0.05) was fitted for Hg concentrations in upper stems to soil Hg concentrations, and Hg concentrations in bottom stems were usually higher than those in upper stems in soil Hg enriched experiment, indicating the combining impact of Hg from air and soil on the accumulation of mercury in stems. Hg concentrations in foliage were significantly correlated (P < 0.05) with air Hg and linearly correlated with soil Hg (R = 0.9983, P = 0.0585), implying that mercury in foliage was mainly from air and some of Hg in root from soil was transferred to foliage through stem. Based on the function in these filed experiments, it was estimated that at least 60%-94% and 56%-77% of mercury in foliage and upper-stem of rice was from the atmosphere respectively, and yet only 8%-56% of mercury in bottom-stem was attributed to air. Therefore, mercury in rice aboveground biomass was mainly from the atmosphere, and these results will provide theoretical basis for the regional atmospheric mercury budgets and the model of mercury cycling.

Colorado River fish monitoring in Grand Canyon, Arizona; 2002–14 humpback chub aggregations

USGS Publications Warehouse

Persons, William R.; Van Haverbeke, David R.; Dodrill, Michael J.

2017-01-31

The humpback chub (Gila cypha) is an endangered cyprinid species endemic to the Colorado River. The largest remaining population of the species spawns and rears in the Little Colorado River in Grand Canyon. Construction and operation of Glen Canyon Dam has altered the main-stem Colorado River in Glen and Grand Canyons. Cold, clear water releases from the dam result in a river that is generally unsuitable for successful humpback chub reproduction. During the early 1990s, nine locations within the main-stem Colorado River were identified as humpback chub aggregations—areas with a consistent and disjunct group of fish with no significant exchange of individuals with other aggregations. We monitored main-stem Colorado River aggregations of humpback chub in Grand Canyon during 2010 to 2014 and compared our results to previous investigations. Relative abundance, as described by catch per unit effort (fish per hour) of adult humpback chub at most main-stem aggregations, generally increased from the 1990s to 2014. In addition, distribution of humpback chub in the main-stem Colorado River has increased since the 1990s. Movement of humpback chub between the Little Colorado River and other aggregations likely adds fish to those aggregations. There is clear evidence of reproduction near the 30-Mile aggregation, and reproduction at Middle Granite Gorge and downstream seems likely based on catches of gravid fish and captures of very young fish, especially during relatively warm water releases from Glen Canyon Dam, 2004 to 2011. Humpback chub relative abundance at Shinumo and Havasu Creek inflows increased following translocations of young humpback chub starting in 2009. In light of this information, we modify the original nine aggregations, combining two previously separate aggregations and dropping two locations to form six distinct aggregations of humpback chub. Trends in humpback chub abundance at main-stem aggregations, relative to management actions (for example, translocations) or changing environmental conditions (for example, river warming), informs management of the species across a riverscape scale within the Colorado River.

Origin, timing, and gene expression profile of adventitious rooting in Arabidopsis hypocotyls and stems.

PubMed

Welander, Margareta; Geier, Thomas; Smolka, Anders; Ahlman, Annelie; Fan, Jing; Zhu, Li-Hua

2014-02-01

Adventitious root (AR) formation is indispensable for vegetative propagation, but difficult to achieve in many crops. Understanding its molecular mechanisms is thus important for such species. Here we aimed at developing a rooting protocol for direct AR formation in stems, locating cellular AR origins in stems and exploring molecular differences underlying adventitious rooting in hypocotyls and stems. In-vitro-grown hypocotyls or stems of wild-type and transgenic ecotype Columbia (Col-0) of Arabidopsis thaliana were rooted on rooting media. Anatomy of AR formation, qRT-PCR of some rooting-related genes and in situ GUS expression were carried out during rooting from hypocotyls and stems. We developed a rooting protocol for AR formation in stems and traced back root origins in stems by anatomical and in situ expression studies. Unlike rooting in hypocotyls, rooting in stems was slower, and AR origins were mainly from lateral parenchyma of vascular bundles and neighboring starch sheath cells as well as, to a lesser extent, from phloem cap and xylem parenchyma. Transcript levels of GH3-3, LBD16, LBD29, and LRP1 in hypocotyls and stems were similar, but transcript accumulation was delayed in stems. In situ expression signals of DR5::GUS, LBD16::GUS, LBD29::GUS, and rolB::GUS reporters in stems mainly occurred at the root initiation sites, suggesting their involvement in AR formation. We have developed an efficient rooting protocol using half-strength Lepoivre medium for studying AR formation in stems, traced back the cellular AR origins in stems, and correlated expression of rooting-related genes with root initiation sites.

Cathodoluminescence in the scanning transmission electron microscope.

PubMed

Kociak, M; Zagonel, L F

2017-05-01

Cathodoluminescence (CL) is a powerful tool for the investigation of optical properties of materials. In recent years, its combination with scanning transmission electron microscopy (STEM) has demonstrated great success in unveiling new physics in the field of plasmonics and quantum emitters. Most of these results were not imaginable even twenty years ago, due to conceptual and technical limitations. The purpose of this review is to present the recent advances that broke these limitations, and the new possibilities offered by the modern STEM-CL technique. We first introduce the different STEM-CL operating modes and the technical specificities in STEM-CL instrumentation. Two main classes of optical excitations, namely the coherent one (typically plasmons) and the incoherent one (typically light emission from quantum emitters) are investigated with STEM-CL. For these two main classes, we describe both the physics of light production under electron beam irradiation and the physical basis for interpreting STEM-CL experiments. We then compare STEM-CL with its better known sister techniques: scanning electron microscope CL, photoluminescence, and electron energy-loss spectroscopy. We finish by comprehensively reviewing recent STEM-CL applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Cathodoluminescence in the scanning transmission electron microscope.

PubMed

Kociak, M; Zagonel, L F

2016-12-19

Cathodoluminescence (CL) is a powerful tool for the investigation of optical properties of materials. In recent years, its combination with scanning transmission electron microscopy (STEM) has demonstrated great success in unveiling new physics in the field of plasmonics and quantum emitters. Most of these results were not imaginable even twenty years ago, due to conceptual and technical limitations. The purpose of this review is to present the recent advances that broke these limitations, and the new possibilities offered by the modern STEM-CL technique. We first introduce the different STEM-CL operating modes and the technical specificities in STEM-CL instrumentation. Two main classes of optical excitations, namely the coherent one (typically plasmons) and the incoherent one (typically light emission from quantum emitters) are investigated with STEM-CL. For these two main classes, we describe both the physics of light production under electron beam irradiation and the physical basis for interpreting STEM-CL experiments. We then compare STEM-CL with its better known sister techniques: scanning electron microscope CL, photoluminescence, and electron energy-loss spectroscopy. We finish by comprehensively reviewing recent STEM-CL applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Volatile Constituents of Three Piper Species from Vietnam.

PubMed

Hieua, Le D; Hoic, Tran M; Thangda, Tran D; Ogunwande, Isiaka A

2015-11-01

The chemical compositions of the essential oils obtained by hydrodistillation of three Piper plants grown in Vietnam are reported. The analysis was achieved by means of gas chromatography with flame ionization detection (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). The main constituents of the leaf oil of Piper majusculum Blume were β-caryophyllene (20.7%), germacrene D (18.6%) and β-elemene (11.3%). The quantitatively significant compounds of the volatile oils of P. harmandii C. DC were sabinene (leaves, 14.5%; stems, 16.2%), benzyl benzoate (leaves, 20.0%; stems, 29.40%) and benzyl salicylate (leaves, 14.1%; stems, 24.3%). Also, α-cadinol (17.0%) was identified in large proportion in the leaf oil. However, sabinene (leaves, 17.9%; stems, 13.5%), benzyl benzoate (leaves, 20.5%; stems, 32.5%) and β-eudesmol (leaves, 13.8%; stems, 8.4%) were the main constituents of P. brevicaule C. DC. This is the first report on the volatile constituents of both P. harmandii and P. brevicaule.

Tuning of major signaling networks (TGF-β, Wnt, Notch and Hedgehog) by miRNAs in human stem cells commitment to different lineages: Possible clinical application.

PubMed

Aval, Sedigheh Fekri; Lotfi, Hajie; Sheervalilou, Roghayeh; Zarghami, Nosratollah

2017-07-01

Two distinguishing characteristics of stem cells, their continuous division in the undifferentiated state and growth into any cell types, are orchestrated by a number of cell signaling pathways. These pathways act as a niche factor in controlling variety of stem cells. The core stem cell signaling pathways include Wingless-type (Wnt), Hedgehog (HH), and Notch. Additionally, they critically regulate the self-renewal and survival of cancer stem cells. Conversely, stem cells' main properties, lineage commitment and stemness, are tightly controlled by epigenetic mechanisms such as DNA methylation, histone modifications and non-coding RNA-mediated regulatory events. MicroRNAs (miRNAs) are cellular switches that modulate stem cells outcomes in response to diverse extracellular signals. Numerous scientific evidences implicating miRNAs in major signal transduction pathways highlight new crosstalks of cellular processes. Aberrant signaling pathways and miRNAs levels result in developmental defects and diverse human pathologies. This review discusses the crosstalk between the components of main signaling networks and the miRNA machinery, which plays a role in the context of stem cells development and provides a set of examples to illustrate the extensive relevance of potential novel therapeutic targets. Copyright © 2017. Published by Elsevier Masson SAS.

Chemical quality of surface waters in the Brazos River basin in Texas

USGS Publications Warehouse

Irelan, Burdge; Mendieta, H.B.

1964-01-01

The quality of water in the lower main stem can be improved by control and disposal of brines in the upper basin. Also, the maximum concentrations in the water of the lower main stem can be lowered by dilution with water stored in reservoirs on tributaries that yield water of good quality.

Seasonal use of small tributary and main-stem habitats by juvenile steelhead, coho salmon, and Dolly Varden in a southeastern Alaska drainage basin.

Treesearch

R.G. Bramblett; M.D. Bryant; B.E. Wright; R.G. White

2002-01-01

The movement of juvenile salmonids between small tributaries and main-stem habitats in southeast Alaska watersheds is poorly understood. We observed movements of steelhead Oncorhynchus mykiss, coho salmon O. kisutch, and Dolly Varden Salvelinus malma between mainstem and tributary habitats at weirs located...

[The structure of vegetative organs, and saponins histochemical localization and content comparization in Polygala sibirica L].

PubMed

Teng, Hong Mei; Fang, Min Feng; Hu, Zheng Hai

2009-02-01

Anatomical, histochemical and phytochemistry methods were used to investigate the structure of vegetative organs, and saponins localization and dynamic changes in Polygala sibirica L. The root consisted of developed periderm and secondary vascular. The secondary phloem was thick, and mainly composed of parenchyma. There were well-developed vessels and fibers in the secondary xylem. The stem was composed of epidermis, cortex and vascular bundle. The ring of sclerenchymatous cells lied between cortex and phloem might be the apoplastic protective screen which could protect the stem from drought. The leaf was bifacial one. The root and stem possessed characteristics adapting to arid environment. Histochemical localization results showed that saponins distributed in secondary phloem and phelloderm of root, in epidermis, cortex and phloem of stem, mainly in mesophyll of leaf. It displayed that saponins accumulated mainly in parenchyma cells of vegetative organs, among of which, the secondary phloem was the main storage site. The HPLC results also showed that the saponins accumulated in all the vegetative organs of Polygala sibirica L., with higher content in roots and lower content in the aerial part that included stems and leaves. The study indicated the aerial part of Polygala sibirica L. also had medicinal value. The saponins content had dynamic variance at the developmental stage, the crude drug should be gathered at period from April to May.

A Multiple Decrement Life Table Reveals That Host Plant Resistance and Parasitism Are Major Causes of Mortality for the Wheat Stem Sawfly.

PubMed

Buteler, Micaela; Peterson, Robert K D; Hofland, Megan L; Weaver, David K

2015-12-01

This study investigated the dynamics of parasitism, host plant resistance, pathogens, and predation on the demography of wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), developing in susceptible (hollow stem) and resistant (solid stem) wheat hosts. This study is also the first to investigate the prevalence and impact of cannibalism on wheat stem sawfly mortality. Wheat stem sawflies were sampled in two commercial wheat fields over 4 yr from the egg stage through adult emergence, and multiple decrement life tables were constructed and analyzed. Cannibalism, host plant resistance, or unknown factors were the most prevalent factors causing egg mortality. Summer mortality of prediapause larvae ranged from 28 to 84%, mainly due to parasitism by Bracon cephi (Gahan) and Bracon lissogaster Muesebeck, cannibalism, and host plant resistance. Winter mortality ranged from 6 to 54% of the overwintering larvae, mainly due to unknown factors or pathogens. Cannibalism is a major cause of irreplaceable mortality because it is absolute, with only a single survivor in every multiple infested stem. Subsequent to obligate cannibalism, mortality of feeding larvae due to host plant resistance was lower in hollow stem wheat than in solid stem wheat. Mortality from host plant resistance was largely irreplaceable. Irreplaceable mortality due to parasitoids was greater in hollow stem wheat than in solid stem wheat. Host plant resistance due to stem solidness and parasitism in hollow stems cause substantial mortality in populations of actively feeding larvae responsible for all crop losses. Therefore, enhancing these mortality factors is vital to effective integrated pest management of wheat stem sawfly. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The Hidden STEM Economy

ERIC Educational Resources Information Center

Rothwell, Jonathan

2013-01-01

Workers in STEM (science, technology, engineering, and math) fields play a direct role in driving economic growth. Yet, because of how the STEM economy has been defined, policymakers have mainly focused on supporting workers with at least a bachelor's (BA) degree, overlooking a strong potential workforce of those with less than a BA. This report…

Changing the Face of STEM with Stormwater Research

ERIC Educational Resources Information Center

Musavi, Mohamad; Friess, Wilhelm A.; James, Cary; Isherwood, Jennifer C.

2018-01-01

Background: The University of Maine Stormwater Management and Research Team (SMART) program began in 2014 with the goal of creating a diverse science-technology-engineering-math (STEM) pathway with community water research. The program engages female and underrepresented minority high school students in locally relevant STEM research. It focuses…

Microhabitat use by brook trout inhabiting small tributaries and a large river main stem: Implications for stream habitat restoration in the central Appalachians

USGS Publications Warehouse

Hansbarger, Jeff L.; Petty, J. Todd; Mazik, Patricia M.

2008-01-01

Brook trout (Salvelinus fontinalis) habitat restoration is needed across a range of stream sizes; however, studies quantifying brook trout habitat preferences in streams of differing sizes are rare. We used radio-telemetry to quantify adult brook trout microhabitat use in a central Appalachian watershed, the upper Shavers Fork of the Cheat River in eastern West Virginia. Our objectives were to: 1) quantify non-random microhabitat use by adult brook trout in the Shavers Fork main stem (drainage area = 32 km2) and an adjacent tributary, Rocky Run (drainage area = 7 km2); and 2) construct stream-specific habitat suitability curves (HSCs) for four important microhabitat variables (depth, average current velocity, maximum current velocity within one meter, and distance to cover). Brook trout used a subset of available microhabitats in both the main stem and Rocky Run: trout tended to occupy microhabitats that were deeper, higher velocity, and closer to cover than expected by chance alone. Although specific microhabitat values differed between the main stem and tributary populations, the overall patterns in brook trout microhabitat use were consistent regardless of stream size. Habitat suitability curves were constructed based on brook trout microhabitat use and will be used to design and monitor the effectiveness of future habitat restoration efforts in the Shavers Fork watershed. Our results suggest that habitat enhancement projects that increase the availability of deep, high velocity microhabitats adjacent to cover would benefit brook trout in both small tributaries and larger river main stems.

The temperature-productivity squeeze: Constraints on brook trout growth along an Appalachian river continuum

USGS Publications Warehouse

Petty, J. Todd; Thorne, David; Huntsman, Brock M.; Mazik, Patricia M.

2014-01-01

We tested the hypothesis that brook trout growth rates are controlled by a complex interaction of food availability, water temperature, and competitor density. We quantified trout diet, growth, and consumption in small headwater tributaries characterized as cold with low food and high trout density, larger tributaries characterized as cold with moderate food and moderate trout density, and large main stems characterized as warm with high food and low trout density. Brook trout consumption was highest in the main stem where diets shifted from insects in headwaters to fishes and crayfish in larger streams. Despite high water temperatures, trout growth rates also were consistently highest in the main stem, likely due to competitively dominant trout monopolizing thermal refugia. Temporal changes in trout density had a direct negative effect on brook trout growth rates. Our results suggest that competition for food constrains brook trout growth in small streams, but access to thermal refugia in productive main stem habitats enables dominant trout to supplement growth at a watershed scale. Brook trout conservation in this region should seek to relieve the “temperature-productivity squeeze,” whereby brook trout productivity is constrained by access to habitats that provide both suitable water temperature and sufficient prey.

Molecular insight in gastric cancer induction: an overview of cancer stemness genes.

PubMed

Akhavan-Niaki, Haleh; Samadani, Ali Akbar

2014-04-01

Gastric cancer is one of the most outgoing human cancers in the world. Two main functional types were described: Intestinal adenocarcinoma and diffuse one. The most important purpose of this review is to analyze and investigate the main genetic factors involved in tumorogenesis of stomach and the molecular mechanism of their expression regulation alongside with the importance of cancer stem cells and their relationship with gastric cancer. It is evident that proper diagnosis of molecular case of cancer may lead to absolute treatment and at least reduction in the disease severity. However, stemness factors such as Sox2, Oct3/4, and Nanog were related with induced pluripotent stem cells, proposing a correlation between these stemness factors and cancer stem cells. Moreover, aberrant induction by Helicobacter pylori of the intestinal-specific homeobox transcription factors, CDX1 and CDX2, also plays an important role in this modification. There are some genes which are directly activated by CDX1 in gastric cancer and distinguished stemness-related reprogramming factors like SALL4 and KLF5. Correspondingly, we also aimed to present the main important epigenetic changes such as DNA methylation, histone modification, and chromatin modeling of stemness genes in disease development. Remarkably, a better understanding of molecular bases of cancer may lead to novel diagnostic, therapeutic, and preventive approaches by some genetic and epigenetic changes such as gene amplifications, gene silencing by DNA methylation, losses of imprinting, LOH, and mutations. Consequently, genome-wide searches of gene expression are widely important for surveying the proper mechanisms of cancer emergence and development. Conspicuously, this review explains an outline of the molecular mechanism and new approaches in gastric cancer.

Looking into the Future: Toward Advanced 3D Biomaterials for Stem-Cell-Based Regenerative Medicine.

PubMed

Liu, Zhongmin; Tang, Mingliang; Zhao, Jinping; Chai, Renjie; Kang, Jiuhong

2018-04-01

Stem-cell-based therapies have the potential to provide novel solutions for the treatment of a variety of diseases, but the main obstacles to such therapies lie in the uncontrolled differentiation and functional engraftment of implanted tissues. The physicochemical microenvironment controls the self-renewal and differentiation of stem cells, and the key step in mimicking the stem cell microenvironment is to construct a more physiologically relevant 3D culture system. Material-based 3D assemblies of stem cells facilitate the cellular interactions that promote morphogenesis and tissue organization in a similar manner to that which occurs during embryogenesis. Both natural and artificial materials can be used to create 3D scaffolds, and synthetic organic and inorganic porous materials are the two main kinds of artificial materials. Nanotechnology provides new opportunities to design novel advanced materials with special physicochemical properties for 3D stem cell culture and transplantation. Herein, the advances and advantages of 3D scaffold materials, especially with respect to stem-cell-based therapies, are first outlined. Second, the stem cell biology in 3D scaffold materials is reviewed. Third, the progress and basic principles of developing 3D scaffold materials for clinical applications in tissue engineering and regenerative medicine are reviewed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Environmental microbial contamination in a stem cell bank.

PubMed

Cobo, F; Concha, A

2007-04-01

The aim of this study was to evaluate the main environmental microbial contaminants of the clean rooms in our stem cell bank. We have measured the microbial air contamination by both passive and active air sampling and the microbial monitoring of surfaces by means of Rodac plates. The environmental monitoring tests were carried out in accordance with the guidelines of European Pharmacopeia and US Pharmacopeia. The micro-organisms were identified by means of an automated system (VITEK 2). During the monitoring, the clean rooms are continually under good manufacturing practices specifications. The most frequent contaminants were Gram-positive cocci. The main contaminants in our stem cell bank were coagulase-negative staphylococci and other opportunistic human pathogens. In order to assure the levels of potential contamination in both embryonic and adult stem cell lines, a continuous sampling of air particles and testing for viable microbiological contamination is necessary. This study is the first evaluation of the environmental contaminants in stem cell banks and can serve as initial evaluation for these establishments. The introduction of environmental monitoring programmes in the processing of stem cell lines could diminish the risk of contamination in stem cell cultures.

Assessing the impacts of river regulation on native bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) habitats in the upper Flathead River, Montana, USA

USGS Publications Warehouse

Muhlfeld, Clint C.; Jones, Leslie A.; Kotter, D.; Miller, William J.; Geise, Doran; Tohtz, Joel; Marotz, Brian

2012-01-01

Hungry Horse Dam on the South Fork Flathead River, Montana, USA, has modified the natural flow regimen for power generation, flood risk management and flow augmentation for anadromous fish recovery in the Columbia River. Concern over the detrimental effects of dam operations on native resident fishes prompted research to quantify the impacts of alternative flow management strategies on threatened bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) habitats. Seasonal and life‐stage specific habitat suitability criteria were combined with a two‐dimensional hydrodynamic habitat model to assess discharge effects on usable habitats. Telemetry data used to construct seasonal habitat suitability curves revealed that subadult (fish that emigrated from natal streams to the river system) bull trout move to shallow, low‐velocity shoreline areas at night, which are most sensitive to flow fluctuations. Habitat time series analyses comparing the natural flow regimen (predam, 1929–1952) with five postdam flow management strategies (1953–2008) show that the natural flow conditions optimize the critical bull trout habitats and that the current strategy best resembles the natural flow conditions of all postdam periods. Late summer flow augmentation for anadromous fish recovery, however, produces higher discharges than predam conditions, which reduces the availability of usable habitat during this critical growing season. Our results suggest that past flow management policies that created sporadic streamflow fluctuations were likely detrimental to resident salmonids and that natural flow management strategies will likely improve the chances of protecting key ecosystem processes and help to maintain and restore threatened bull trout and westslope cutthroat trout populations in the upper Columbia River Basin.

Using bioenergetics modeling to estimate consumption of native juvenile salmonids by nonnative northern pike in the Upper Flathead River System, Montana

USGS Publications Warehouse

Muhlfeld, C.C.; Bennett, D.H.; Kirk, Steinhorst R.; Marotz, B.; Boyer, M.

2008-01-01

Introductions of nonnative northern pike Esox lucius have created recreational fisheries in many waters in the United States and Canada, yet many studies have shown that introduced northern pike may alter the composition and structure of fish communities through predation. We estimated the abundance of nonnative northern pike (2002-2003) and applied food habits data (1999-2003) to estimate their annual consumption of native bull trout Salvelinus confluentus and westslope cutthroat trout Oncorhynchus clarkii lewisi juveniles in the upper Flathead River system, Montana. Population estimates were generally consistent among years and ranged from 1,200 to 1,300 individuals. Westslope cutthroat trout were present in the diet of younger (???600 mm) and older (>600 mm) northern pike during all seasons and bull trout were found only in larger northern pike during all seasons but summer. Bioenergetics modeling estimated that the northern pike population annually consumed a total of 8.0 metric tons (mt) of fish flesh; the highest biomass was composed of cyprinids (4.95 mt) followed by whitefishes Prosopium spp. (1.02 mt), bull trout (0.80 mt), westslope cutthroat trout (0.68 mt), yellow perch Perca flavescens (0.41 mt),1 and other fishes (centrarchids and cottids; 0.14 mt). Numerically, the northern pike population consumed more than 342,000 fish; cyprinids and catostomids comprised approximately 82% of prey fish (278,925), whereas over 13,000 westslope cutthroat trout and nearly 3,500 bull trout were eaten, comprising about 5% of the prey consumed. Our results suggest that predation by introduced northern pike is contributing to the lower abundance of native salmonids in the system and that a possible benefit might accrue to native salmonids by reducing these predatory interactions. ?? Copyright by the American Fisheries Society 2008.

Assessing distribution of migratory fishes and connectivity following complete and partial dam removals in a North Carolina River

USGS Publications Warehouse

Raabe, Joshua K.; Hightower, Joseph E.

2014-01-01

Fish, especially migratory species, are assumed to benefit from dam removals that restore connectivity and access to upstream habitat, but few studies have evaluated this assumption. Therefore, we assessed the movement of migratory fishes in the springs of 2008 through 2010 and surveyed available habitat in the Little River, North Carolina, a tributary to the Neuse River, after three complete dam removals and one partial (notched) dam removal. We tagged migratory fishes with PIT tags at a resistance-board weir located at a dam removal site (river kilometer [rkm] 3.7) and followed their movements with an array of PIT antennas. The river-wide distribution of fish following removals varied by species. For example, 24–31% of anadromous American Shad Alosa sapidissima, 45–49% of resident Gizzard Shad Dorosoma cepedianum, and 4–11% of nonnative Flathead CatfishPylodictis olivaris passed the dam removal site at rkm 56 in 2009 and 2010. No preremoval data were available for comparison, but reach connectivity appeared to increase as tagged individuals passed former dam sites and certain individuals moved extensively both upstream and downstream. However, 17–28% did not pass the partially removed dam at rkm 7.9, while 20–39% of those that passed remained downstream for more than a day before migrating upstream. Gizzard Shad required the deepest water to pass this notched structure, followed by American Shad then Flathead Catfish. Fish that passed the notched dam accessed more complex habitat (e.g., available substrate size-classes) in the middle and upper reaches. The results provide strong support for efforts to restore currently inaccessible habitat through complete removal of derelict dams.

Distributions of small nongame fishes in the lower Yellowstone River

USGS Publications Warehouse

Duncan, Michael B.; Bramblett, Robert G.; Zale, Alexander V.

2016-01-01

The Yellowstone River is the longest unimpounded river in the conterminous United States. It has a relatively natural flow regime, which helps maintain diverse habitats and fish assemblages uncommon in large rivers elsewhere. The lower Yellowstone River was thought to support a diverse nongame fish assemblage including several species of special concern. However, comprehensive data on the small nongame fish assemblage of the lower Yellowstone River is lacking. Therefore, we sampled the Yellowstone River downstream of its confluence with the Clark’s Fork using fyke nets and otter trawls to assess distributions and abundances of small nongame fishes. We captured 42 species (24 native and 18 nonnative) in the lower Yellowstone River with fyke nets. Native species constituted over 99% of the catch. Emerald shiners Notropis atherinoides, western silvery minnows Hybognathus argyritis, flathead chubs Platygobio gracilis, sand shiners Notropis stramineus, and longnose dace Rhinichthys cataractae composed nearly 94% of fyke net catch and were caught in every segment of the study area. We captured 24 species by otter trawling downstream of the Tongue River. Sturgeon chubs Macrhybopsis gelida, channel catfish Ictalurus punctatus, flathead chubs, stonecats Noturus flavus, and sicklefin chubs Macrhybopsis meeki composed 89% of the otter trawl catch. The upstream distributional limit of sturgeon chubs in the Yellowstone River was the Tongue River; few sicklefin chubs were captured above Intake Diversion Dam. This study not only provides biologists with baseline data for future monitoring efforts on the Yellowstone River but serves as a benchmark for management and conservation efforts in large rivers elsewhere as the Yellowstone River represents one of the best references for a naturally functioning Great Plains river.

Association of green stem disorder with agronomic traits in soybean

USDA-ARS?s Scientific Manuscript database

Green stem disorder (GSD) of soybean is the occurrence of non-senescent, fleshy green stems of plants with normal, fully mature pods and seeds. The main focus of this study was to determine the relationship between GSD incidence and agronomic traits and to determine if GSD incidence was associated w...

Developing Non-Formal Education Competences as a Complement of Formal Education for STEM Lecturers

ERIC Educational Resources Information Center

Terrazas-Marín, Roy Alonso

2018-01-01

This paper focuses on a current practice piece on professional development for university lecturers, transformative learning, dialogism and STEM (Science, Technology, Engineering and Mathematics) education. Its main goals are to identify the key characteristics that allow STEM educators to experiment with the usage of non-formal education…

Essential oils and crude extracts from Chrysanthemum trifurcatum leaves, stems and roots: chemical composition and antibacterial activity.

PubMed

Sassi, Ahlem Ben; Skhiri, Fethia Harzallah; Chraief, Imed; Bourgougnon, Nathalie; Hammami, Mohamed; Aouni, Mahjoub

2014-01-01

The essential oils from the leaves, stems and roots of Chrysanthemum trifurcatum (Desf.) Batt. and Trab. var. macrocephalum (viv.) were obtained by hydrodistillation and their chemical compositions were analysed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), in order to get insight into similarities and differences as to their active composition. A total of fifty compounds were identified, constituting 97.84%, 99.02% and 98.20% of total oil composition of the leaves, stems and roots, respectively. Monoterpene hydrocarbons were shown to be the main group of constituents of the leaves and stems parts in the ratio of 67.88% and 51.29%, respectively. But, the major group in the roots oil was found to be sesquiterpene hydrocarbons (70.30%). The main compounds in leaves oil were limonene (26.83%), γ-terpinene (19.68%), α-pinene (9.7%) and α-terpenyl acetate (7.16%). The stems oil, contains mainly limonene (32.91%), 4-terpenyl acetate (16.33%) and γ-terpinene (5.93%), whereas the main compounds in roots oil were α-calacorene (25.98%), α-cedrene (16.55%), β-bourbobene (14.91%), elemol (7.45%) and 2-hexenal (6.88%). The crude organic extracts of leaves, stems and roots, obtained by maceration with solvents of increasing polarity: petroleum ether, ethyl acetate and methanol, contained tannins, flavonoids and alkaloids. Meanwhile, essential oils and organic extracts were tested for antibacterial activities against eight Gram-positive and Gram-negative strains, using a microdilution method. The oil and methanolic extact from C. trifurcatum leaves showed a great potential of antibacterial effect against Bacillus subtilis and Staphylococcus epidermidis, with an IC50 range of 31.25-62.5 µg/ml.

Can brook trout survive climate change in large rivers? If it rains.

PubMed

Merriam, Eric R; Fernandez, Rodrigo; Petty, J Todd; Zegre, Nicolas

2017-12-31

We provide an assessment of thermal characteristics and climate change vulnerability for brook trout (Salvelinus fontinalis) habitats in the upper Shavers Fork sub-watershed, West Virginia. Spatial and temporal (2001-2015) variability in observed summer (6/1-8/31) stream temperatures was quantified in 23 (9 tributary, 14 main-stem) reaches. We developed a mixed effects model to predict site-specific mean daily stream temperature from air temperature and discharge and coupled this model with a hydrologic model to predict future (2016-2100) changes in stream temperature under low (RCP 4.5) and high (RCP 8.5) emissions scenarios. Observed mean daily stream temperature exceeded the 21°C brook trout physiological threshold in all but one main-stem site, and 3 sites exceeded proposed thermal limits for either 63- and 7-day mean stream temperature. We modeled mean daily stream temperature with a high degree of certainty (R 2 =0.93; RMSE=0.76°C). Predicted increases in mean daily stream temperature in main-stem and tributary reaches ranged from 0.2°C (RCP 4.5) to 1.2°C (RCP 8.5). Between 2091 and 2100, the average number of days with mean daily stream temperature>21°C increased within main-stem sites under the RCP 4.5 (0-1.2days) and 8.5 (0-13) scenarios; however, no site is expected to exceed 63- or 7-day thermal limits. During the warmest 10years, ≥5 main-stem sites exceeded the 63- or 7-day thermal tolerance limits under both climate emissions scenarios. Years with the greatest increases in stream temperature were characterized by low mean daily discharge. Main-stem reaches below major tributaries never exceed thermal limits, despite neighboring reaches having among the highest observed and predicted stream temperatures. Persistence of thermal refugia within upper Shavers Fork would enable persistence of metapopulation structure and life history processes. However, this will only be possible if projected increases in discharge are realized and offset expected increases in air temperature. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Streamflow and selenium loads during synoptic sampling of the Gunnison River and its tributaries near Delta, Colorado, November 2015

USGS Publications Warehouse

Stevens, Michael R.; Leib, Kenneth J.; Thomas, Judith C.; Bauch, Nancy J.; Richards, Rodney J.

2018-06-13

In response to the need for more information about selenium (Se) sources and transport, the U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board, completed a study that characterized Se loads in a reach of the Gunnison River between Delta and Grand Junction, Colo. This report identifies where possible dissolved Se loading is occurring in a study reach in the Lower Gunnison River Basin between Delta and Grand Junction on November 19, 2015.The combined Se loads from the Gunnison River at Delta (site 3) and the Uncompahgre River at Delta (site 4) were about 95 percent of the load at the furthest downstream main-stem sample location at the Gunnison River below Roubideau Creek near Delta (site 20) (31.6 and 33.4 pounds per day, respectively), indicating that about 5 percent of the total load (1.8 pounds) was potentially contributed from diffuse groundwater inflow. Main-stem streamflow accounting during November 2015 in a downstream direction was not supportive of substantial net gains or losses in the main-stem water balance.The cumulative load from measured tributary inflows downstream from the Uncompahgre River confluence only amounted to 1.2 pounds of the main-stem loads (1.8 pounds gain) from site 4 to the end of the synoptic reach at site 20. The remaining 33 percent (about 0.6 pounds) of Se load increase was not accounted for by known tributary inflow. Yet, the small changes in the streamflow mass balance in the same reach does not strongly support a net inflow explanation for the apparent gain in load.Based on the results of the loading and streamflow analysis, when errors in the loading estimates are considered, there is no conclusive evidence of an appreciable amount of Se load that is unaccounted for in the study reach of the Gunnison River as was originally hypothesized. Differences determined from comparisons of cumulative tributary loads and Gunnison River main-stem loads for this study are within error estimates of the main-stem loads.

Seasonal and diel variation in xylem CO2 concentration and sap pH in sub-Mediterranean oak stems.

PubMed

Salomón, Roberto; Valbuena-Carabaña, María; Teskey, Robert; McGuire, Mary Anne; Aubrey, Doug; González-Doncel, Inés; Gil, Luis; Rodríguez-Calcerrada, Jesús

2016-04-01

Since a substantial portion of respired CO2 remains within the stem, diel and seasonal trends in stem CO2 concentration ([CO2]) are of major interest in plant respiration and carbon budget research. However, continuous long-term stem [CO2] studies are scarce, and generally absent in Mediterranean climates. In this study, stem [CO2] was monitored every 15min together with stem and air temperature, sap flow, and soil water storage during a growing season in 16 stems of Quercus pyrenaica to elucidate the main drivers of stem [CO2] at different temporal scales. Fluctuations in sap pH were also assessed during two growing seasons to evaluate potential errors in estimates of the concentration of CO2 dissolved in xylem sap ([CO2*]) calculated using Henry's law. Stem temperature was the best predictor of stem [CO2] and explained more than 90% and 50% of the variability in stem [CO2] at diel and seasonal scales, respectively. Under dry conditions, soil water storage was the main driver of stem [CO2]. Likewise, the first rains after summer drought caused intense stem [CO2] pulses, suggesting enhanced stem and root respiration and increased resistance to radial CO2 diffusion. Sap flow played a secondary role in controlling stem [CO2] variations. We observed night-time sap pH acidification and progressive seasonal alkalinization. Thus, if the annual mean value of sap pH (measured at midday) was assumed to be constant, night-time sap [CO2*] was substantially overestimated (40%), and spring and autumn sap [CO2*] were misestimated by 25%. This work highlights that diel and seasonal variations in temperature, tree water availability, and sap pH substantially affect xylem [CO2] and sap [CO2*]. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Cord-Blood Banking

MedlinePlus

... cord blood mainly because of the promise that stem cell research holds for the future. Most of us would have little use for stem cells now, but research into using them to treat diseases is ongoing — ...

Developing equations for estimating tree component biomass for naturally regenerated shorteaf pine in southeast Oklahoma with application to biomass partitioning in thinned and unthinned stands

Treesearch

Nabin Gyawali; Thomas B. Lynch; Rodney E. Will

2013-01-01

Traditionally, the main focus of forest production has usually been to maximize allocation of biomass to merchantable stem wood. But the assessment of biomass partitioning in stands is needed to address management concerns such as stem production and allocation, carbon sequestration, wildland fire, whole tree harvesting, etc. Thinning mainly increases the bole diameter...

Comment on "A new method for treating fecal incontinence by implanting stem cells derived from human adipose tissue: preliminary findings of a randomized double-blind clinical trial".

PubMed

El-Said, Mohammed Mohammed; Emile, Sameh Hany

2018-04-25

In the study by Sarveazad et al. adipose tissue-derived stem cells were injected to reinforce anal sphincter repair. The authors came to the conclusion that injection of stem cells during repair surgery for fecal incontinence may cause replacement of fibrous tissue, which may be a key point in treatment of fecal incontinence. The authors emphasized in their "Discussion" section that the ability of stem cells to differentiate into muscle fibers, replacing the fibrous tissue at the site of repair, is their main action, which may not be accurate. We think that healing of repaired anal sphincter begins with granulation tissue formation, which then matures into fibrous tissue that becomes infiltrated by muscle fibers from the approximated cut ends of the sphincter, resulting in regain of sphincter muscle continuity. This is supported by many experimental studies that have evaluated local injection of stem cells during sphincteroplasty in rats and shown that the injected stem cells do not differentiate into muscle fibers but may induce healing by a strong fibrous tissue. Further studies are needed to determine the main mechanism of action of mesenchymal stems cells in augmenting anal sphincter repair.

WRKY13 acts in stem development in Arabidopsis thaliana.

PubMed

Li, Wei; Tian, Zhaoxia; Yu, Diqiu

2015-07-01

Stems are important for plants to grow erectly. In stems, sclerenchyma cells must develop secondary cell walls to provide plants with physical support. The secondary cell walls are mainly composed of lignin, xylan and cellulose. Deficiency of overall stem development could cause weakened stems. Here we prove that WRKY13 acts in stem development. The wrky13 mutants take on a weaker stem phenotype. The number of sclerenchyma cells, stem diameter and the number of vascular bundles were reduced in wrky13 mutants. Lignin-synthesis-related genes were repressed in wrky13 mutants. Chromatin immunoprecipitation assays proved that WRKY13 could directly bind to the promoter of NST2. Taken together, we proposed that WRKY13 affected the overall development of stem. Identification of the role of WRKY13 may help to resolve agricultural problems caused by weaker stems. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

An evaluation of the STEMS tree growth projection system.

Treesearch

Margaret R. Holdaway; Gary J. Brand

1983-01-01

STEMS (Stand and Tree Evaluation and Modeling System) is a tree growth projection system. This paper (1) compares the performance of the current version of STEMS developed for the Lake States with that of the original model and (2) reports the results of an analysis of the current model over a wide range of conditions and identifies its main strengths and weaknesses...

Flowering branches cause injuries to second-year main stems of Artemisia tridentata nutt. subspecies tridentata

Treesearch

Lance S. Evans; Angela Citta; Stewart C. Sanderson

2012-01-01

Eccentricity of stems of Artemisia tridentata Nutt. (big sagebrush) has been reported previously. Analysis of samples observed over 2 years documented that each stem terminal produces about 8-10 branches each year, and during second-year growth, 3-8 of these develop into short, flowering, determinate branches. Each flowering branch produces hundreds of seeds and then...

Middle School Science and Mathematics Teachers' Conceptions of the Nature of Science: A One-Year Study on the Effects of Explicit and Reflective Online Instruction

ERIC Educational Resources Information Center

Wong, Sissy S.; Firestone, Jonah B.; Ronduen, Lionnel G.; Bang, EunJin

2016-01-01

Science, Technology, Engineering, and Mathematics (STEM) education has become one of the main priorities in the United States. Science education communities and researchers advocate for integration of STEM disciplines throughout the teaching curriculum. This requires teacher knowledge in STEM disciplines, as well as competence in scientific…

Effects of historical land-cover changes on flooding and sedimentation, North Fish Creek, Wisconsin

USGS Publications Warehouse

Fitzpatrick, Faith A.; Knox, James C.; Whitman, Heather E.

1999-01-01

Results from hydrologic and sediment-transport modeling indicate that modern flood peaks and sediment loads in North Fish Creek may be double that expected under pre-settlement forest cover. During maximum agricultural activity in the mid-1920's to mid-1930's, flood peaks probably were about 3 times larger and sediment loads were about 5 times larger than expected under pre-settlement forest cover. These results indicate that future changes from pasture or cropland to forest will help reduce flood peaks, thereby reducing erosion and sedimentation. The addition of detention basins (to decrease flood peaks) on tributaries to North Fish Creek, or bank and instream restoration (to decrease erosion) in the upper main stem, also may help reduce the contribution of sediment from the upper main stem to the transitional section and lower main stem of the creek.

Intravascular ultrasound and angiographic demonstration of left main stem thrombus-high-risk presentation in a young adult with anabolic steroid abuse.

PubMed

Garg, Pankaj; Davis, Gershan; Wilson, John Ian; Sivananthan, Mohan

2010-01-01

We present a case of acute myocardial infarction in a young adult with a history of anabolic steroid abuse. On diagnostic coronary angiography and intravascular ultrasound, he was found to have a distal left main stem thrombus extending into the proximal left anterior descending artery and a large intermediate vessel. As he was hemodynamically stable and pain-free, he was managed conservatively with triple antiplatelet therapy (aspirin, clopidogrel, and abciximab). This was also to avoid the risk of 'wiring the vessel,' especially if there was underlying dissection. Repeat angiography a few weeks later showed complete thrombus resolution. This is the first reported case of extensive left main stem thrombus in a young patient with anabolic steroid abuse. Management of such cases is not straightforward and our case highlights one approach to both diagnosis and treatment.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whittaker, Peter A.

A brief outline of stem cells, stem cell therapy and therapeutic cloning is given. The position of therapeutic cloning with regard to other embryonic manipulations - IVF-based reproduction, embryonic stem formation from IVF embryos and reproductive cloning - is indicated. The main ethically challenging stages in therapeutic cloning are considered to be the nuclear transfer process including the source of eggs for this and the destruction of an embryo to provide stem cells for therapeutic use. The extremely polarised nature of the debate regarding the status of an early human embryo is noted, and some potential alternative strategies for preparingmore » immunocompatible pluripotent stem cells are indicated.« less

Surface- and ground-water characteristics in the Upper Truckee River and Trout Creek watersheds, South Lake Tahoe, California and Nevada, July-December 1996

USGS Publications Warehouse

Rowe, T.G.; Allander, Kip K.

2000-01-01

The Upper Truckee River and Trout Creek watersheds, South Lake Tahoe, California and Nevada, were studied from July to December 1996 to develop a better understanding of the relation between surface water and ground water. Base flows at 63 streamflow sites were measured in late September 1996 in the Upper Truckee River and Trout Creek watersheds. Most reaches of the main stem of the Upper Truckee River and Trout Creek had gaining or steady flows, with one losing reach in the mid-section of each stream. Twenty-seven of the streamflow sites measured in the Upper Truckee River watershed were on 14 tributaries to the main stem of the Upper Truckee River. Sixteen of the 40 streamflow sites measured in the Upper Truckee River watershed had no measurable flow. Streamflow in Upper Truckee River watershed ranged from 0 to 11.6 cubic feet per second (ft3/s). The discharge into Lake Tahoe from the Upper Truckee River was 11.6 ft3/s, of which, 40 percent of the flow was from ground-water discharge into the main stem, 40 percent was from tributary inflows, and the remaining 20 percent was the beginning flow. Gains from or losses to ground water along streams ranged from a 1.4 cubic feet per second per mile (ft3/s/mi) gain to a 0.5 ft3/s/mi loss along the main stem. Fourteen of the streamflow sites measured in the Trout Creek watershed were on eight tributaries to the main stem of Trout Creek. Of the 23 streamflow sites measured in the Trout Creek watershed, only one site had no flow. Flows in the Trout Creek watershed ranged from zero to 23.0 ft3/s. Discharge into Lake Tahoe from Trout Creek was 23.0 ft3/s, of which, about 5 percent of the flow was from ground-water discharge into the main stem, 75 percent was from tributary inflows, and the remaining 20 percent was the beginning flow. Ground-water seepage rates ranged from a 1.4 ft3/s/mi gain to a 0.9 ft3/s/mi loss along the main stem. Specific conductances measured during the seepage run in September 1996 increased in a downstream direction in the main stem of the Upper Truckee River and remained relatively constant in the main stem of Trout Creek. Water temperatures measured during the seepage run also increased in a downstream direction in both watersheds. Depths to ground water measured at 62 wells in the study area were used with the results of the seepage run to produce a water-level map in the Upper Truckee River and Trout Creek watersheds. Ground-water levels ranged from 1.3 to 69.8 feet below land surface. In the upper sections of the watersheds ground-water flow is generally toward the main stems of Upper Truckee River and Trout Creek, whereas in the lower sections, ground-water flow generally parallels the two streams and flows toward Lake Tahoe. The altitude of ground water between Lake Tahoe and Highway 50 was nearly the same as the lake-surface altitude from July to November 1996. This suggests ground-water discharge beneath the Upper Truckee River and Trout Creek drainages directly to Lake Tahoe was minimal and that much of the ground-water discharge was to the channels of the Upper Truckee River and Trout Creek upstream from Highway 50. Hydraulic gradients ranged from near zero to 1,400 feet per mile. Samples were collected at six surface-water-quality and eight ground-water-quality sites from July through mid-December 1996. Specific conductance of the ground-water-quality sites was higher than that of the surface-water-quality sites. Water temperature and pH median values were similar between ground-water-quality and surface-water-quality sites but ground water had greater variation in pH and surface water had greater variation in water temperature. Ground-water nutrient concentrations were generally higher than those in streams except for bioreactive iron.

Generalized sediment budgets of the Lower Missouri River, 1968–2014

USGS Publications Warehouse

Heimann, David C.

2016-09-13

Sediment budgets of the Lower Missouri River were developed in a study led by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers. The scope of the study included the development of a long-term (post-impoundment, 1968–2014) average annual sediment budget and selected annual, monthly, and daily sediment budgets for a reach and period that adequate data were available. Included in the analyses were 31 main-stem and tributary stations of the Lower Missouri River and two Mississippi River stations—the Mississippi River below Grafton, Illinois, and the Mississippi River at St. Louis, Missouri.Long-term average annual suspended-sediment loads of Missouri River main-stem stations ranged from 0.33 million tons at the Missouri River at Yankton, South Dakota, station to 71.2 million tons at Missouri River at Hermann, Mo., station. Gaged tributary gains accounted for 9–36 percent of the local reach budgets and cumulative gaged tributary contributions accounted for 84 percent of the long-term average suspended-sediment load of the Missouri River at Hermann, Mo., station. Although the sediment budgets for seven defined main-stem reaches generally were incomplete—missing bedload, reach storage, and ungaged tributary contributions—the budget residuals (net result of sediment inputs and outputs) for six of the seven reaches ranged from -7.0 to 1.7 million tons, or from -9.2 to 4.0 percent of the reach output suspended-sediment load, and were within the 10 percent reported measurement error of annual suspended-sediment loads for large rivers. The remaining reach, downstream from Gavin’s Point Dam, extended from Yankton, S. Dak., to Sioux City, Iowa, and had a budget residual of -9.8 million tons, which was -88 percent of the suspended-sediment load at Sioux City.The Lower Missouri River reach from Omaha, Nebraska, to Nebraska City, Nebr., had periods of concurrent sediment data for each primary budget component with which to analyze and determine a suspended-sediment budget for selected annual, monthly, and daily time increments. The temporal changes in the cumulative annual budget residuals were poorly correlated with the comparatively steady 1968–2011 annual stage trends at the Missouri River at Nebraska City, Nebr., station. An accurate total sediment budget is developed by having concurrent data available for all primary suspended and bedload components for a reach of interest throughout a period. Such a complete budget, with concurrent record for suspended-sediment load and bedload components, is unavailable for any reach and period in the Lower Missouri River. The primary data gaps are in bedload data, and also in suspended-sediment gains and losses including ungaged tributary inputs and sediment storage. Bedload data gaps in the Missouri River Basin are much more prevalent than suspended-sediment data gaps, and the first step in the development of reach bedload budgets is the establishment of a standardized bedload monitoring program at main-stem stations.The temporal changes in flow-adjusted suspended-sediment concentrations analyzed at main-stem Missouri River stations indicated an overall downward change in concentrations between 1968 and 2014. Temporary declines in flow-adjusted suspended-sediment concentrations during and following large floods were evident but generally returned to near pre-flood values within about 6 months.Data uncertainties associated with the development of a sediment budget include uncertainties associated with the collection of suspended-sediment and bedload data and the computation of suspended-sediment loads. These uncertainties vary depending on the frequency of data collection, the variability of conditions being represented by the discrete samples, and the statistical approach to suspended-sediment load computations. The coefficients of variation of suspended-sediment loads of Missouri River tributary stations for 1968–2014 were greater, 75.0 percent, than the main-stem stations, 47.1 percent. The lower coefficient of variation at main-stem stations compared to tributaries, primarily is the result of the lower variability in streamflow and sediment discharge identified at main-stem stations. To obtain similar accuracy between suspended-sediment loads at main-stem and tributary stations, a longer period of record is required of the tributary stations. During 1968–2014, however, the Missouri River main-stem station record was much more complete (87 percent) than the tributary station record (28 percent).

Pathogenic bacteria and microbial-source tracking markers in Brandywine Creek Basin, Pennsylvania and Delaware, 2009-10

USGS Publications Warehouse

Duris, Joseph W.; Reif, Andrew G.; Olson, Leif E.; Johnson, Heather E.

2011-01-01

The City of Wilmington, Delaware, is in the downstream part of the Brandywine Creek Basin, on the main stem of Brandywine Creek. Wilmington uses this stream, which drains a mixed-land-use area upstream, for its main drinking-water supply. Because the stream is used for drinking water, Wilmington is in need of information about the occurrence and distribution of specific fecally derived pathogenic bacteria (disease-causing bacteria) and their relations to commonly measured fecal-indicator bacteria (FIB), as well as information regarding the potential sources of the fecal pollution and pathogens in the basin. This study focused on five routinely sampled sites within the basin, one each on the West Branch and the East Branch of Brandywine Creek and at three on the main stem below the confluence of the West and East Branches. These sites were sampled monthly for 1 year. Targeted event samples were collected on two occasions during high flow and two occasions during normal flow. On the basis of this study, high flows in the Brandywine Creek Basin were related to increases in FIB densities, and in the frequency of selected pathogen and source markers, in the West Branch and main stem of Brandywine Creek, but not in the East Branch. Water exceeding the moderate fullbody-contact single-sample recreational water-quality criteria (RWQC) for Escherichia coli (E. coli) was more likely to contain selected markers for pathogenic E. coli (eaeA,stx1, and rfbO157 gene markers) and bovine fecal sources (E. hirae and LTIIa gene markers), whereas samples exceeding the enterococci RWQC were more likely to contain the same pathogenic markers but also were more likely to carry a marker indicative of human source (esp gene marker). On four sample dates, during high flow between October and March, the West Branch was the only observed potential contributor of selected pathogen and bovine source markers to the main stem of Brandywine Creek. Indeed, the stx2 marker, which indicates a highly virulent type of pathogenic E. coli, was found only in the West Branch and main stem at high flow but was not found in the East Branch under similar conditions. However, it must be noted that throughout the entire year of sampling there were occasions, during both high and normal flows, when both the East and West Branches were potential contributors of pathogen and microbial-source tracking markers to the main stem. Therefore, this study indicates that under selected conditions (high flow, October through March), West Branch Brandywine Creek Basin was the most likely source of elevated FIB densities in the main stem. These elevated densities are associated with more frequent detection of selected pathogenic E. coli markers (rfbO157 stx1) and are associated with MST markers of bovine source. However, during other times of the year, both the West Branch and East Branch Basins are acting as potential sources of FIB and fecally derived pathogens.

Multipotent Stem Cell and Reproduction.

PubMed

Khanlarkhani, Neda; Baazm, Maryam; Mohammadzadeh, Farzaneh; Najafi, Atefeh; Mehdinejadiani, Shayesteh; Sobhani, Aligholi

Stem cells are self-renewing and undifferentiated cell types that can be differentiate into functional cells. Stem cells can be classified into two main types based on their source of origin: Embryonic and Adult stem cells. Stem cells also classified based on the range of differentiation potentials into Totipotent, Pluripotent, Multipotent, and Unipotent. Multipotent stem cells have the ability to differentiate into all cell types within one particular lineage. There are plentiful advantages and usages for multipotent stem cells. Multipotent Stem cells act as a significant key in procedure of development, tissue repair, and protection. The accessibility and adaptability of these amazing cells create them a great therapeutic choice for different part of medical approaches, and it becomes interesting topic in the scientific researches to found obvious method for the most advantageous use of MSC-based therapies. Recent studies in the field of stem cell biology have provided new perspectives and opportunities for the treatment of infertility disorders.

Determining Sediment Sources in the Anacostia River Watershed

NASA Astrophysics Data System (ADS)

Devereux, O. H.; Needelman, B. A.; Prestegaard, K. L.; Gellis, A. C.; Ritchie, J. C.

2005-12-01

Suspended sediment is a water-quality problem in the Chesapeake Bay. This project is designed to identify sediment sources in an urban watershed, the Northeast Branch of the Anacostia River (in Washington, D.C. and Maryland - drainage area = 188.5 km2), which delivers sediment directly to the Bay. This watershed spans two physiographic regions - the Piedmont and Coastal Plain. Bank sediment and suspended-sediment deposits were characterized using the following techniques: radionuclide (Cs-137) analysis by gamma ray spectrometry, trace-element analysis by ICP-MS, clay mineralogy by XRD, and particle-size analysis by use of a laser particle-size analyzer. Sampling of bank and suspended sediment was designed to: a) characterize tributary inputs from both Piedmont and Coastal Plain sources, and b) differentiate tributary inputs from bank erosion along the main stem of the Northeast Branch. Thirteen sample sites were chosen that represent tributary source areas of each physiographic region and the main stem where mixing occurs. Surface samples of the banks were compared to overbank deposits from a ten year storm (a proxy for the suspended sediments). Fingerprint components are selected from these data. Cesium-137 concentrations were analyzed for bank and overbank deposits for each physiographic region. No clear differences were seen between the two physiographic regions. Significant differences were observed between upland tributaries and the main stem of the Anacostia River. The average activity of Cs-137 for the tributaries was 5.4 bq/kg and the average for the main stem was 1.1 bq/kg. This suggests that there is significant erosion and storage of sediment in the tributaries. The low activity from Cs-137 in the main stem suggests a lack of storage of sediment along the main stem of the river. For the trace-element data, we focused on elements that showed significant variation among the sites. For the bank sediment, these elements include: Sr, V, Y, Ce, and Nd. For the overbank deposits, Zr, V, Ba, Ce, and Cu showed significant variability. In both physiographic regions, Pb is primarily found in bank deposits, while Cu is found in higher concentrations in overbank deposits. The Cs-137 data clearly showed the erosion and storage of sediment patterns in the watershed. The trace-element data indicate that stream banks may be differentiated from overbank deposits.

SU-E-I-39: Molecular Image Guided Cancer Stem Cells Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abdollahi, H

Purpose: Cancer stem cells resistance to radiation is a problematic issue that has caused a big fail in cancer treatment. Methods: As a primary work, molecular imaging can indicate the main mechanisms of radiation resistance of cancer stem cells. By developing and commissioning new probes and nanomolecules and biomarkers, radiation scientist will able to identify the essential pathways of radiation resistance of cancer stem cells. As the second solution, molecular imaging is a best way to find biological target volume and delineate cancer stem cell tissues. In the other hand, by molecular imaging techniques one can image the treatment responsemore » in tumor and also in normal tissue. In this issue, the response of cancer stem cells to radiation during therapy course can be imaged, also the main mechanisms of radiation resistance and finding the best radiation modifiers (sensitizers) can be achieved by molecular imaging modalities. In adaptive radiotherapy the molecular imaging plays a vital role to have higher tumor control probability by delivering high radiation doses to cancer stem cells in any time of treatment. The outcome of a feasible treatment is dependent to high cancer stem cells response to radiation and removing all of which, so a good imaging modality can show this issue and preventing of tumor recurrence and metastasis. Results: Our results are dependent to use of molecular imaging as a new modality in the clinic. We propose molecular imaging as a new radiobiological technique to solve radiation therapy problems due to cancer stem cells. Conclusion: Molecular imaging guided cancer stem cell diagnosis and therapy is a new approach in the field of cancer treatment. This new radiobiological imaging technique should be developed in all clinics as a feasible tool that is more biological than physical imaging.« less

19. DETAIL VIEW OF SKIFF BOW WITH OAK STEM AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. DETAIL VIEW OF SKIFF BOW WITH OAK STEM AND FRAMES PLANKED IN CEDAR USING COPPER CLINCH NAILS. TRANSOM OF SECOND SKIFF CAN BE SEEN BACKGROUND. - Lowell's Boat Shop, 459 Main Street, Amesbury, Essex County, MA

National Hematopoietic Stem Cells Transplant Registry in Poland: Nationwide Internet Reporting System and Results.

PubMed

Łęczycka, A; Dudkiewicz, M; Czerwiński, J; Malanowski, P; Żalikowska-Hołoweńko, J; Danielewicz, R

2016-06-01

History of hematopoietic stem cell transplantations in Poland begins in early 1980s; the 1st bone marrow allotransplantation was performed in 1983 in the Central Clinical Hospital of the Military Medical Academy in Warsaw. Following years brought the 1st autologous stem cell transplantations. Ten years later, unrelated bone marrow transplantation was performed for the 1st time by the team of the Hematology and Blood and Marrow Transplantation Unit in Katowice. Since then, hematopoietic stem cell transplantation developed to be standard procedure and one of the most important therapies applied in leukemia treatment. The number of allotransplantations in Poland has grown significantly in the past 2 decades, which generated new needs and problems. In 2005, based on a new Transplant Law, a National Transplants Registry was created. Its main role is to collect data (registration of procedures and follow-up data) related to every transplantation case for stem cells and tissues as well as for organs. We present statistics concerning stem cell transplantations performed in Poland, as collected in the National Transplants Registry in the years 2006-2014. There are 18 centers transplanting hematopoietic stem cells in Poland. The total number of hematopoietic stem cell transplantations performed in 2006-2014 was 3,537, with allotransplantations from relatives accounted for 1,491 and from unrelated donors for 2,046. The main indication for allotransplantation in past years was acute leukemia. Copyright © 2016 Elsevier Inc. All rights reserved.

Historical early stem development of northern white-cedar (Thuja occidentalis L.) in Maine

Treesearch

Philip V. Hofmeyer; Laura S. Kenefic; Robert S. Seymour

2010-01-01

We used stem analysis to quantify early height and diameter growth rates of 80 northern white-cedar trees (17.4-55.0 cm dbh) harvested in 2005 and 2006 in central and northern Maine. It took an average of 42 years (range, 9-86 years) for sampled trees to grow from stump height to sapling size, 96 years to grow to pole size (range, 28-171), 140 years to grow to...

Promises and challenges of stem cell research for regenerative medicine.

PubMed

Power, Carl; Rasko, John E J

2011-11-15

In recent years, stem cells have generated increasing excitement, with frequent claims that they are revolutionizing medicine. For those not directly involved in stem cell research, however, it can be difficult to separate fact from fiction or realistic expectation from wishful thinking. This article aims to provide internists with a clear and concise introduction to the field. While recounting some scientific and medical milestones, the authors discuss the 3 main varieties of stem cells-adult, embryonic, and induced pluripotent-comparing their advantages and disadvantages for clinical medicine. The authors have sought to avoid the moral and political debates surrounding stem cell research, focusing instead on scientific and medical issues.

Morphometry of the coronary ostia and the structure of coronary arteries in the shorthair domestic cat

PubMed Central

Barszcz, Karolina; Kupczyńska, Marta; Klećkowska-Nawrot, Joanna; Janeczek, Maciej; Goździewska-Harłajczuk, Karolina; Dzierzęcka, Małgorzata; Janczyk, Paweł

2017-01-01

The aim of this study was to measure the area of the coronary ostia, assess their localization in the coronary sinuses and to determine the morphology of the stem of the left and right coronary arteries in the domestic shorthair cat. The study was conducted on 100 hearts of domestic shorthair cats of both sexes, aged 2–18 years, with an average body weight of 4.05 kg. A morphometric analysis of the coronary ostia was carried out on 52 hearts. The remaining 48 hearts were injected with a casting material in order to carry out a morphological assessment of the left and right coronary arteries. In all the studied animals, the surface of the left coronary artery ostium was larger than the surface of the right coronary artery ostium. There were four types of the left main coronary artery: type I (23 animals, 49%)–double-branched left main stem (giving off the left circumflex branch and the interventricular paraconal branch, which in turn gave off the septal branch), type II (12 animals, 26%)–double-branched left main stem (giving off the left circumflex branch and the interventricular paraconal branch without the septal branch), type III (11 animals, 23%)–triple-branched left main stem (giving off the left circumflex branch, interventricular branch and the septal branch, type IV (1 animal, 2%)–double-branched left main stem (giving off the interventricular paraconal branch and the left circumflex branch, which in turn gave off the septal branch). The left coronary artery ostium is greater than the right one. There is considerable diversity in the branches of proximal segment of the left coronary artery, while the right coronary artery is more conservative. These results can be useful in defining the optimal strategies in the endovascular procedures involving the coronary arteries or the aortic valve in the domestic shorthair cat. PMID:29020103

Impacts of the Columbia River hydroelectric system on main-stem habitats of fall chinook salmon

USGS Publications Warehouse

Dauble, D.D.; Hanrahan, T.P.; Geist, D.R.; Parsley, M.J.

2003-01-01

Salmonid habitats in main-stem reaches of the Columbia and Snake rivers have changed dramatically during the past 60 years because of hydroelectric development and operation. Only about 13% and 58% of riverine habitats in the Columbia and Snake rivers, respectively, remain. Most riverine habitat is found in the upper Snake River; however, it is upstream of Hells Canyon Dam and not accessible to anadromous salmonids. We determined that approximately 661 and 805 km of the Columbia and Snake rivers, respectively, were once used by fall chinook salmon Oncorhynchus tshawytscha for spawning. Fall chinook salmon currently use only about 85 km of the main-stem Columbia River and 163 km of the main-stem Snake River for spawning. We used a geomorphic model to identify three river reaches downstream of present migration barriers with high potential for restoration of riverine processes: the Columbia River upstream of John Day Dam, the Columbia-Snake-Yakima River confluence, and the lower Snake River upstream of Little Goose Dam. Our analysis substantiated the assertion that historic spawning areas for fall chinook salmon occurred primarily within wide alluvial floodplains, which were once common in the mainstem Columbia and Snake rivers. These areas possessed more unconsolidated sediment and more bars and islands and had lower water surface slopes than did less extensively used areas. Because flows in the main stem are now highly regulated, the predevelopment alluvial river ecosystem is not expected to be restored simply by operational modification of one or more dams. Establishing more normative flow regimes - specifically, sustained peak flows for scouring - is essential to restoring the functional characteristics of existing, altered habitats. Restoring production of fall chinook salmon to any of these reaches also requires that population genetics and viability of potential seed populations (i.e., from tributaries, tailrace spawning areas, and hatcheries) be considered.

The Emerging Role of PEDF in Stem Cell Biology

PubMed Central

Elahy, Mina; Baindur-Hudson, Swati; Dass, Crispin R.

2012-01-01

Encoded by a single gene, PEDF is a 50 kDa glycoprotein that is highly conserved and is widely expressed among many tissues. Most secreted PEDF deposits within the extracellular matrix, with cell-type-specific functions. While traditionally PEDF is known as a strong antiangiogenic factor, more recently, as this paper highlights, PEDF has been linked with stem cell biology, and there is now accumulating evidence demonstrating the effects of PEDF in a variety of stem cells, mainly in supporting stem cell survival and maintaining multipotency. PMID:22675247

Plant stem cell niches.

PubMed

Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

2012-01-01

Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis.

Nuclear Mechanics and Stem Cell Differentiation.

PubMed

Mao, Xinjian; Gavara, Nuria; Song, Guanbin

2015-12-01

Stem cells are characterized by their self-renewal and multi-lineage differentiation potential. Stem cell differentiation is a prerequisite for the application of stem cells in regenerative medicine and clinical therapy. In addition to chemical stimulation, mechanical cues play a significant role in regulating stem cell differentiation. The integrity of mechanical sensors is necessary for the ability of cells to respond to mechanical signals. The nucleus, the largest and stiffest cellular organelle, interacts with the cytoskeleton as a key mediator of cell mechanics. Nuclear mechanics are involved in the complicated interactions of lamins, chromatin and nucleoskeleton-related proteins. Thus, stem cell differentiation is intimately associated with nuclear mechanics due to its indispensable role in mechanotransduction and mechanical response. This paper reviews several main contributions of nuclear mechanics, highlights the hallmarks of the nuclear mechanics of stem cells, and provides insight into the relationship between nuclear mechanics and stem cell differentiation, which may guide clinical applications in the future.

GREAT I: A Study of the Upper Mississippi River. Volume 1. Main Report

DTIC Science & Technology

1980-09-01

management of the river system and its interrelated Ensure necessary capability to components within the river corridor . maintain the total river...stem corridor will is a complex resource. It means many probably directly modify many or all things to many people. To call it a other components of the...resource in the "resource" implies that it is some- main stem corridor , Any description thing which man can draw on to satisfy of the Upper

Skin Stem Cells: At the Frontier Between the Laboratory and Clinical Practice. Part 1: Epidermal Stem Cells.

PubMed

Pastushenko, I; Prieto-Torres, L; Gilaberte, Y; Blanpain, C

2015-11-01

Stem cells are characterized by their ability to self-renew and differentiate into the different cell lineages of their tissue of origin. The discovery of stem cells in adult tissues, together with the description of specific markers for their isolation, has opened up new lines of investigation, expanding the horizons of biomedical research and raising new hope in the treatment of many diseases. In this article, we review in detail the main characteristics of the stem cells that produce the specialized cells of the skin (epidermal, mesenchymal, and melanocyte stem cells) and their potential implications and applications in diseases affecting the skin. Part I deals with the principal characteristics and potential applications of epidermal stem cells in dermatology. Copyright © 2015 Elsevier España, S.L.U. and AEDV. All rights reserved.

Vertical gradients and seasonal variation in stem CO2 efflux within a Norway spruce stand.

PubMed

Tarvainen, Lasse; Räntfors, Mats; Wallin, Göran

2014-05-01

Stem CO2 efflux is known to vary seasonally and vertically along tree stems. However, annual tree- and stand-scale efflux estimates are commonly based on measurements made only a few times a year, during daytime and at breast height. In this study, the effect of these simplifying assumptions on annual efflux estimates and their influence on the estimates of the importance of stems in stand-scale carbon cycling are evaluated. In order to assess the strength of seasonal, diurnal and along-stem variability in CO2 efflux, half-hourly measurements were carried out at three heights on three mature Norway spruce (Picea abies (L.) Karst.) trees over a period of 3 years. Making the common assumption of breast height efflux rates being representative of the entire stem was found to result in underestimations of 10-17% in the annual tree-scale CO2 efflux. Upscaling using only daytime measurements from breast height increased the underestimation to 15-20%. Furthermore, the results show that the strength of the vertical gradient varies seasonally, being strongest in the early summer and non-existent during the cool months. The observed seasonality in the vertical CO2 efflux gradient could not be explained by variation in stem temperature, temperature response of the CO2 efflux (Q10), outer-bark permeability, CO2 transport in the xylem or CO2 release from the phloem. However, the estimated CO2 concentration immediately beneath the bark was considerably higher in the upper stem during the main period of diameter growth, coinciding with the strongest vertical efflux gradient. These results suggest that higher growth rates in the upper stem are the main cause for the observed vertical variation in the stem CO2 effluxes. Furthermore, the results indicate that accounting for the vertical efflux variation is essential for assessments of the importance of stems in stand-scale carbon cycling. © The Author 2014. Published by Oxford University Press. All rights reserved.

Evidence for circulating cancer stem-like cells and epithelial-mesenchymal transition phenotype in the pleurospheres derived from lung adenocarcinoma using liquid biopsy.

PubMed

Mirza, Sheefa; Jain, Nayan; Rawal, Rakesh

2017-03-01

Lung cancer stem cells are supposed to be the main drivers of tumor initiation, maintenance, drug resistance, and relapse of the disease. Hence, identification of the cellular and molecular aspects of these cells is a prerequisite for targeted therapy of lung cancer. Currently, analysis of circulating tumor cells has the potential to become the main diagnostic technique to monitor disease progression or therapeutic response as it is non-invasive. However, accurate detection of circulating tumor cells has remained a challenge, as epithelial cell markers used so far are not always trustworthy for detecting circulating tumor cells, especially during epithelial-mesenchymal transition. As cancer stem cells are the only culprit to initiate metastatic tumors, our aim was to isolate and characterize circulating tumor stem cells rather than circulating tumor cells from the peripheral blood of NSCLC adenocarcinoma as limited data are available addressing the gene expression profiling of lung cancer stem cells. Here, we reveal that CD44(+)/CD24(-) population in circulation not only exhibit stem cell-related genes but also possess epithelial-mesenchymal transition characteristics. In conclusion, the use of one or more cancer stem cell markers along with epithelial, mesenchymal and epithelial mesenchymal transition markers will prospectively provide the most precise assessment of the threat for recurrence and metastatic disease and has a great potential for forthcoming applications in harvesting circulating tumor stem cells and their downstream applications. Our results will aid in developing diagnostic and prognostic modalities and personalized treatment regimens like dendritic cell-based immunotherapy that can be utilized for targeting and eliminating circulating tumor stem cells, to significantly reduce the possibility of relapse and improve clinical outcomes.

Stem cells’ guided gene therapy of cancer: New frontier in personalized and targeted therapy

PubMed Central

Mavroudi, Maria; Zarogoulidis, Paul; Porpodis, Konstantinos; Kioumis, Ioannis; Lampaki, Sofia; Yarmus, Lonny; Malecki, Raf; Zarogoulidis, Konstantinos; Malecki, Marek

2014-01-01

Introduction Diagnosis and therapy of cancer remain to be the greatest challenges for all physicians working in clinical oncology and molecular medicine. The statistics speak for themselves with the grim reports of 1,638,910 men and women diagnosed with cancer and nearly 577,190 patients passed away due to cancer in the USA in 2012. For practicing clinicians, who treat patients suffering from advanced cancers with contemporary systemic therapies, the main challenge is to attain therapeutic efficacy, while minimizing side effects. Unfortunately, all contemporary systemic therapies cause side effects. In treated patients, these side effects may range from nausea to damaged tissues. In cancer survivors, the iatrogenic outcomes of systemic therapies may include genomic mutations and their consequences. Therefore, there is an urgent need for personalized and targeted therapies. Recently, we reviewed the current status of suicide gene therapy for cancer. Herein, we discuss the novel strategy: genetically engineered stem cells’ guided gene therapy. Review of therapeutic strategies in preclinical and clinical trials Stem cells have the unique potential for self renewal and differentiation. This potential is the primary reason for introducing them into medicine to regenerate injured or degenerated organs, as well as to rejuvenate aging tissues. Recent advances in genetic engineering and stem cell research have created the foundations for genetic engineering of stem cells as the vectors for delivery of therapeutic transgenes. Specifically in oncology, the stem cells are genetically engineered to deliver the cell suicide inducing genes selectively to the cancer cells only. Expression of the transgenes kills the cancer cells, while leaving healthy cells unaffected. Herein, we present various strategies to bioengineer suicide inducing genes and stem cell vectors. Moreover, we review results of the main preclinical studies and clinical trials. However, the main risk for therapeutic use of stem cells is their cancerous transformation. Therefore, we discuss various strategies to safeguard stem cell guided gene therapy against iatrogenic cancerogenesis. Perspectives Defining cancer biomarkers to facilitate early diagnosis, elucidating cancer genomics and proteomics with modern tools of next generation sequencing, and analyzing patients’ gene expression profiles provide essential data to elucidate molecular dynamics of cancer and to consider them for crafting pharmacogenomics-based personalized therapies. Streamlining of these data into genetic engineering of stem cells facilitates their use as the vectors delivering therapeutic genes into specific cancer cells. In this realm, stem cells guided gene therapy becomes a promising new frontier in personalized and targeted therapy of cancer. PMID:24860662

Index of stations; surface-water data-collections network of Texas, September 1993

USGS Publications Warehouse

Gandara, S.C.; Jones, R.E.

1995-01-01

Table 1 shows the station number and name, latitude and longitude, type of station, and the office principally responsible for collection of the data. An 8-digit permanent numerical designation for all gaging stations has been adopted on a nationwide basis; stations are numbered and listed in downstream order. In the downstream direction along the main stem, all stations on a tributary entering between two main-stem stations are listed between them. A similar order is followed in listing stations by first rank, second rank, and other ranks of tributaries. The rank of any tributary with respect to the stream to which it is an immediate tributary is indicated by an indention in the table. Each indention represents one rank. This downstream order and system of indention shows which gaging stations are on tributaries between any two stations on a main stem and the rank of the tributary on which each gaging station is situated.

Index of stations: surface-water data-collection network of Texas, September 1995

USGS Publications Warehouse

Gandara, S.C.; Jones, R.E.

1996-01-01

Table 1 shows the station number and name, latitude and longitude, type of station, and the office responsible for the collection of the data and the record. An 8-digit permanent numerical designation for all gaging stations has been adopted on a nationwide basis; stations are numbered and listed in downstream order. In the downstream direction along the main stem, all stations on a tributary entering between two main-stem stations are listed between them. A similar order is followed in listing stations by first rank, second rank, and other ranks of tributaries. The rank of any tributary with respect to the stream to which it is an immediate tributary is indicated by an indention in the table. Each indention represents one rank. This downstream order and system of indention shows which gaging stations are on tributaries between any two stations on a main stem and the rank of the tributary on which each gaging station is situated.

Evaluation of Musa (Paradisiaca Linn. cultivar)--"Puttubale" stem juice for antilithiatic activity in albino rats.

PubMed

Prasad, K V; Bharathi, K; Srinivasan, K K

1993-10-01

The fresh juice of Musa stem (Puttubale) was tested for its antilithiatic activity. Zinc discs were implanted in the urinary bladder of albino rats to induce urolithiasis. The stones formed were mainly of magnesium ammonium phosphate with traces of calcium oxalate. Musa stem juice (3 mL/rat/day orally) was found to be effective in reducing the formation and also in dissolving the pre-formed stones.

Regulation of correlative inhibition of axillary bud outgrowth by basal branches varies with growth stage in Trifolium repens

PubMed Central

Thomas, Roderick G.; Hay, Michael J. M.

2015-01-01

In Trifolium repens the decline in bud outgrowth that occurs with distance from basal root systems is due to correlative inhibition by the first-formed basal branches. The apical and axillary buds on these basal branches are the source of the inhibitory effect, but their mode of action is unclear. Inhibition might occur via basal branches being a sink for xylem-transported branching stimulants or alternatively by providing a source of inhibitory signals, or by both mechanisms. To distinguish between these mechanisms, four experiments were conducted on plants varying in initial growth stage from 10 to 19 nodes along their main stems to determine any variation in the relative importance of the operative mechanisms of correlative inhibition. Inhibitory signal exported into the main stem, detected as a branching response to girdling of basal branches, was relatively more significant in smaller (initially with 10–15 nodes on the main stem) than in larger (>19 nodes on main stem) plants. This signal was shown not to involve auxin fluxes, and is unidentified. However, across all stages of growth, the predominant mechanism driving correlative inhibition was the action of axillary and apical buds of basal branches as sinks for the stimulatory signal. This study indicates that the relative importance of the mechanisms regulating bud outgrowth in T. repens varies with growth stage and that, during intermediate stages, regulation has some similarity to that in Pisum. PMID:25922495

Trichome density of main stem is tightly linked to PepMoV resistance in chili pepper (Capsicum annuum L.).

PubMed

Kim, Hyun Jung; Han, Jung-Heon; Kim, Seungill; Lee, Heung Ryul; Shin, Jun-Sung; Kim, Jeong-Ho; Cho, Juok; Kim, Young Ho; Lee, Hee Jae; Kim, Byung-Dong; Choi, Doil

2011-04-01

A relationship between pepper trichome and pepper mottle virus (PepMoV) resistance was examined. In an intraspecific F(2) mapping population from the cross between Capsicum annuum CM334 (trichome-bearing and PepMoV resistant) and Chilsungcho (glabrous and PepMoV susceptible), major QTLs for both traits were identified by composite interval mapping in linkage group (LG) 24 corresponding a telomere region on pepper chromosome 10. Ptel1 of putative trichome enhancing locus was a common major QTL for trichome density on the main stem and calyx. Ptel1 apart from HpmsE031 at a 1.03 cM interval was specifically associated to the trichome density on the main stem, whereas Ptel2 near m104 marker on LG2 was specific for the calyx trichome. Epistatic analysis indicated that Ptel1 engaged in controlling the trichome density by mutual interactions with the organ-specific QTLs. For PepMoV resistance, two QTLs (Pep1 and Pep2) were identified on the LG 24. Pep1 was located with Ptel1 in the R-gene cluster (RGC) for potyvirus resistance including Pvr4 with broad spectrum resistance to potyviruses. Pep1 flanking TG420 marker seemed to be the major factors determining correlation with PepMoV resistance. These results indicate that the level of trichome density on pepper main stem can be used as a morphological marker for Pvr4 in pepper breeding.

The Core of Sibling Stem Cell Donation - A Grounded Theory Study.

PubMed

Kisch, Annika M; Forsberg, Anna

2017-01-01

There is a lack of theoretical framework supporting stem cell transplant nurses in their assessment, judgment and caring interventions of sibling stem cell donors. The purpose of this study was to explore sibling stem cell donors' main concerns and how they deal with them before and after donation. Ten healthy sibling donors, 5 men and 5 women, with a median age of 54 years were included in this study when they were due to donate stem cells to a brother or sister. Data were collected prospectively on three occasions (before the donation and three and twelve months after it) through in-depth interviews, which were recorded and transcribed verbatim for analysis by the Grounded Theory method according to Charmaz. This study describes the efforts of the ten donors to fulfil their duty as a sibling by doing what they considered necessary in order to help. Their efforts were summarised in a process wherein the grounded theory generated three main categories; Prepare, Promote and Preserve. A clear path of transition leading to fulfilment is evident, starting before the donation and continuing for one year afterwards. Being a sibling stem cell donor means doing what you have to do to fulfil your duty and if possible, saving the life of a seriously ill brother or sister. The relationship between the siblings is strengthened by the donation process. Sibling stem cell donation appears to be about fulfilment and the theoretical framework may support clinicians in their evaluation and support of donors.

Silencing of ATP11B by RNAi-Induced Changes in Neural Stem Cell Morphology.

PubMed

Wang, Jiao; Wang, Qian; Zhou, Fangfang; Wang, Dong; Wen, Tieqiao

2017-01-01

RNA interference (RNAi) technology is one of the main research tools in many studies of neural stem cells. This study describes effects of ATP11B on the morphology change of neural stem cells by using RNAi. ATP11B belongs to P4-ATPases family, which is preferential translocate phosphatidylserine of cell membrane. Although it exists in neural stem cells, its physiological function is poorly understood. By using RNAi technology to downregulate expression of ATP11B, we found distinct morphological changes in neural stem cells. More important, psiRNA-ATP11B-transfected cells displayed short neurite outgrowth compared to the control cells. These data strongly suggest that ATP11B plays a key role in the morphological change of neural stem cells.

Characters related to higher starch accumulation in cassava storage roots

PubMed Central

Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

2016-01-01

Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed. PMID:26892156

Characters related to higher starch accumulation in cassava storage roots.

PubMed

Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

2016-02-19

Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed.

How Mockups, a Key Engineering Tool, Help to Promote Science, Technology, Engineering, and Mathematics Education

NASA Technical Reports Server (NTRS)

McDonald, Harry E.

2010-01-01

The United States ranking among the world in science, technology, engineering, and mathematics (STEM) education is decreasing. To counteract this problem NASA has made it part of its mission to promote STEM education among the nation s youth. Mockups can serve as a great tool when promoting STEM education in America. The Orion Cockpit Working Group has created a new program called Students Shaping America s Next Space Craft (SSANS) to outfit the Medium Fidelity Orion Mockup. SSANS will challenge the students to come up with unique designs to represent the flight design hardware. There are two main types of project packages created by SSANS, those for high school students and those for university students. The high school projects will challenge wood shop, metal shop and pre-engineering classes. The university projects are created mainly for senior design projects and will require the students to perform finite element analysis. These projects will also challenge the undergraduate students in material selection and safety requirements. The SSANS program will help NASA in its mission to promote STEM education, and will help to shape our nations youth into the next generation of STEM leaders.

Modeling the leaf angle dynamics in rice plant.

PubMed

Zhang, Yonghui; Tang, Liang; Liu, Xiaojun; Liu, Leilei; Cao, Weixing; Zhu, Yan

2017-01-01

The leaf angle between stem and sheath (SSA) is an important rice morphological trait. The objective of this study was to develop and validate a dynamic SSA model under different nitrogen (N) rates for selected rice cultivars. The time-course data of SSA were collected in three years, and a dynamic SSA model was developed for different main stem leaf ranks under different N rates for two selected rice cultivars. SSA increased with tiller age. The SSA of the same leaf rank increased with increase in N rate. The maximum SSA increased with leaf rank from the first to the third leaf, then decreased from the third to the final leaf. The relationship between the maximum SSA and leaf rank on main stem could be described with a linear piecewise function. The change of SSA with thermal time (TT) was described by a logistic equation. A variety parameter (the maximum SSA of the 3rd leaf on main stem) and a nitrogen factor were introduced to quantify the effect of cultivar and N rate on SSA. The model was validated against data collected from both pot and field experiments. The relative root mean square error (RRMSE) was 11.56% and 14.05%, respectively. The resulting models could be used for virtual rice plant modeling and plant-type design.

Stem CO2 efflux in six co-occurring tree species: underlying factors and ecological implications.

PubMed

Rodríguez-Calcerrada, Jesús; López, Rosana; Salomón, Roberto; Gordaliza, Guillermo G; Valbuena-Carabaña, María; Oleksyn, Jacek; Gil, Luis

2015-06-01

Stem respiration plays a role in species coexistence and forest dynamics. Here we examined the intra- and inter-specific variability of stem CO2 efflux (E) in dominant and suppressed trees of six deciduous species in a mixed forest stand: Fagus sylvatica L., Quercus petraea [Matt.] Liebl, Quercus pyrenaica Willd., Prunus avium L., Sorbus aucuparia L. and Crataegus monogyna Jacq. We conducted measurements in late autumn. Within species, dominants had higher E per unit stem surface area (Es ) mainly because sapwood depth was higher than in suppressed trees. Across species, however, differences in Es corresponded with differences in the proportion of living parenchyma in sapwood and concentration of non-structural carbohydrates (NSC). Across species, Es was strongly and NSC marginally positively related with an index of drought tolerance, suggesting that slow growth of drought-tolerant trees is related to higher NSC concentration and Es . We conclude that, during the leafless period, E is indicative of maintenance respiration and is related with some ecological characteristics of the species, such as drought resistance; that sapwood depth is the main factor explaining variability in Es within species; and that the proportion of NSC in the sapwood is the main factor behind variability in Es among species. © 2014 John Wiley & Sons Ltd.

Aging, metabolism and stem cells: Spotlight on muscle stem cells.

PubMed

García-Prat, Laura; Muñoz-Cánoves, Pura

2017-04-15

All tissues and organs undergo a progressive regenerative decline as they age. This decline has been mainly attributed to loss of stem cell number and/or function, and both stem cell-intrinsic changes and alterations in local niches and/or systemic environment over time are known to contribute to the stem cell aging phenotype. Advancing in the molecular understanding of the deterioration of stem cell cells with aging is key for targeting the specific causes of tissue regenerative dysfunction at advanced stages of life. Here, we revise exciting recent findings on why stem cells age and the consequences on tissue regeneration, with a special focus on regeneration of skeletal muscle. We also highlight newly identified common molecular pathways affecting diverse types of aging stem cells, such as altered proteostasis, metabolism, or senescence entry, and discuss the questions raised by these findings. Finally, we comment on emerging stem cell rejuvenation strategies, principally emanating from studies on muscle stem cells, which will surely burst tissue regeneration research for future benefit of the increasing human aging population. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Would Increasing Engineering Literacies Enable Untapped Opportunities for STEM Education?

ERIC Educational Resources Information Center

Redman, Christine

2017-01-01

The main focus here is to examine the benefits of defining and developing an engineering curriculum for elementary schools. Like many other international educational systems, Australian educational settings have been seeking to effectively implement science, technology, engineering, and mathematics (STEM) education. However, current assumptions…

Stem cells - biological update and cell therapy progress

PubMed Central

GIRLOVANU, MIHAI; SUSMAN, SERGIU; SORITAU, OLGA; RUS-CIUCA, DAN; MELINCOVICI, CARMEN; CONSTANTIN, ANNE-MARIE; MIHU, CARMEN MIHAELA

2015-01-01

In recent years, the advances in stem cell research have suggested that the human body may have a higher plasticity than it was originally expected. Until now, four categories of stem cells were isolated and cultured in vivo: embryonic stem cells, fetal stem cells, adult stem cells and induced pluripotent stem cells (hiPSCs). Although multiple studies were published, several issues concerning the stem cells are still debated, such as: the molecular mechanisms of differentiation, the methods to prevent teratoma formation or the ethical and religious issues regarding especially the embryonic stem cell research. The direct differentiation of stem cells into specialized cells: cardiac myocytes, neural cells, pancreatic islets cells, may represent an option in treating incurable diseases such as: neurodegenerative diseases, type I diabetes, hematologic or cardiac diseases. Nevertheless, stem cell-based therapies, based on stem cell transplantation, remain mainly at the experimental stages and their major limitation is the development of teratoma and cancer after transplantation. The induced pluripotent stem cells (hiPSCs) represent a prime candidate for future cell therapy research because of their significant self-renewal and differentiation potential and the lack of ethical issues. This article presents an overview of the biological advances in the study of stem cells and the current progress made in the field of regenerative medicine. PMID:26609255

Larval feeding behavior and ant association in frosted elfin, Callophrys irus (Lycaenidae)

USGS Publications Warehouse

Albanese, G.; Nelson, M.W.; Vickery, P.D.; Sievert, P.R.

2007-01-01

Callophrys irus is a rare and declining lycaenid found in the eastern U.S., inhabiting xeric and open habitats maintained by disturbance. Populations are localized and monophagous. We document a previously undescribed larval feeding behavior in both field and lab reared larvae in which late instar larvae girdled the main stem of the host plant. Girdled stems provide a unique feeding sign that was useful in detecting the presence of larvae in the field. We also observed frequent association of field larvae with several species of ants and provide a list of ant species. We suggest two hypotheses on the potential benefits of stem-girdling to C. irus larvae: 1) Stem girdling provides phloem sap as a larval food source and increases the leaf nutrient concentration, increasing larval growth rates and providing high quality honeydew for attending ants; 2) Stem girdling reduces stem toxicity by inhibiting transport of toxins from roots to the stem.

Global fit concept in revision hip arthroplasty for cementless press-fit femoral stems.

PubMed

Canovas, F; LeBeguec, P; Batard, J; Gaillard, F; Dagneaux, L

2017-06-01

A revision stem may be required after a femoral extended trochanteric osteotomy (ETO) is made during revision hip arthroplasty. The two main complications of straight cementless femoral stems are subsidence due to inadequate osteointegration and stress-shielding. We will describe an original revision method with ETO that uses a straight cementless stem. The goal of this method was to achieve the most extensive press-fit possible during stem implantation to improve the transmission of stresses to the bone and to prevent reduction in bone density. The intramedullary preparation was done after closure and fixation of the ETO, which allows impaction of the revision stem with metaphyseal and diaphyseal press-fit. We report encouraging results with preservation of periprosthetic bone stock and good osteointegration of these revision stems at the final follow-up. Pronounced sagittal curvature or large bone defects are contraindications for this technique. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Survival of Atlantic salmon Salmo salar smolts through a hydropower complex.

PubMed

Stich, D S; Bailey, M M; Zydlewski, J D

2014-10-01

This study evaluated Atlantic salmon Salmo salar smolt survival through the lower Penobscot River, Maine, U.S.A., and characterized relative differences in proportional use and survival through the main-stem of the river and an alternative migration route, the Stillwater Branch. The work was conducted prior to removal of two main-stem dams and operational changes in hydropower facilities in the Stillwater Branch. Survival and proportional use of migration routes in the lower Penobscot were estimated from multistate (MS) models based on 6 years of acoustic telemetry data from 1669 smolts and 2 years of radio-telemetry data from 190 fish. A small proportion (0·12, 95% c.i. = 0·06-0·25) of smolts used the Stillwater Branch, and mean survival through the two operational dams in this part of the river was relatively high (1·00 and 0·97). Survival at Milford Dam, the dam that will remain in the main-stem of the Penobscot River, was relatively low (0·91), whereas survival through two dams that were removed was relatively high (0·99 and 0·98). Smolt survival could decrease in the Stillwater Branch with the addition of two new powerhouses while continuing to meet fish passage standards. The effects of removing two dams in the main-stem are expected to be negligible for smolt survival based on high survival observed from 2005 to 2012 at those locations. Survival through Milford Dam was been well below current regulatory standards, and thus improvement of passage at this location offers the best opportunity for improving overall smolt survival in the lower river. © 2014 The Fisheries Society of the British Isles.

Survival of Atlantic salmon Salmo salar smolts through a hydropower complex

USGS Publications Warehouse

Stich, D.S.; Bailey, M.M.; Zydlewski, Joseph D.

2014-01-01

This study evaluated Atlantic salmon Salmo salar smolt survival through the lower Penobscot River, Maine, U.S.A., and characterized relative differences in proportional use and survival through the main-stem of the river and an alternative migration route, the Stillwater Branch. The work was conducted prior to removal of two main-stem dams and operational changes in hydropower facilities in the Stillwater Branch. Survival and proportional use of migration routes in the lower Penobscot were estimated from multistate (MS) models based on 6 years of acoustic telemetry data from 1669 smolts and 2 years of radio-telemetry data from 190 fish. A small proportion (0·12, 95% c.i. = 0·06–0·25) of smolts used the Stillwater Branch, and mean survival through the two operational dams in this part of the river was relatively high (1·00 and 0·97). Survival at Milford Dam, the dam that will remain in the main-stem of the Penobscot River, was relatively low (0·91), whereas survival through two dams that were removed was relatively high (0·99 and 0·98). Smolt survival could decrease in the Stillwater Branch with the addition of two new powerhouses while continuing to meet fish passage standards. The effects of removing two dams in the main-stem are expected to be negligible for smolt survival based on high survival observed from 2005 to 2012 at those locations. Survival through Milford Dam was been well below current regulatory standards, and thus improvement of passage at this location offers the best opportunity for improving overall smolt survival in the lower river.

Assessment of resource selection models to predict occurrence of five juvenile flatfish species (Pleuronectidae) over the continental shelf in the western Gulf of Alaska

NASA Astrophysics Data System (ADS)

Wilson, Matthew T.; Mier, Kathryn L.; Cooper, Dan W.

2016-05-01

According to the nursery size hypothesis, flatfish recruitment is constrained by nursery area. Thus, if resource selection models can be shown to accurately predict the location and geographic extent of flatfish nursery areas, they will become important tools in the management and study of flatfish population dynamics. We demonstrate that some resource selection models derived previously to predict the presence and absence of juvenile flatfishes near shore were applicable to the broader continental shelf. For other age-species groups, derivation of new models for the continental shelf was necessary. Our study was conducted in the western Gulf of Alaska (GoA) during October 2011 on four groups of age-0 juvenile flatfishes: Pacific halibut (Hippoglossus stenolepis), arrowtooth flounder (Atheresthes stomias), northern rock sole (Lepidopsetta polyxystra), and flathead sole (Hippoglossoides elassodon); and three groups of age-1 juvenile flatfishes: northern rock sole, flathead sole, and yellowfin sole (Limanda aspera). Sampling occurred at 33 sites across the continental shelf. Fish were collected using a 3-m beam trawl, and a midwater trawl. Environmental data were collected on sediment composition and water temperature and depth. Many of the age-species groups co-occurred in the Shumagin and Barnabus sea valleys; however, age-0 arrowtooth flounder occurred at more locations than other juveniles, perhaps due to a relatively broad tolerance of environmental conditions and to the utilization of midwater habitat. Thus, the large nursery area of arrowtooth flounder may be one reason why they are currently the most abundant GoA flatfish. In fact, among all species, mean recruitment at age 3 increased with the percent occurrence of age-0 juveniles at the 33 sites, a proxy for relative nursery area, in accordance with the nursery size hypothesis, suggesting that mean recruitment among GoA flatfishes is structured by nursery size.

Flathead River Basin Hydrologic Observatory, Northern Rocky Mountains

NASA Astrophysics Data System (ADS)

Woessner, W. W.; Running, S. W.; Potts, D. F.; Kimball, J. S.; Deluca, T. H.; Fagre, D. B.; Makepeace, S.; Hendrix, M. S.; Lorang, M. S.; Ellis, B. K.; Lafave, J.; Harper, J.

2004-12-01

We are proposing the 22, 515 km2 glacially-sculpted Flathead River Basin located in Montana and British Columbia as a Hydrologic Observatory. This hydrologic landscape is diverse and includes large pristine watersheds, rapidly developing intermountain valleys, and a 95 km2 regulated reservoir and 510 km2 lake. The basin has a topographic gradient of over 2,339 m, and spans high alpine to arid climatic zones and a range of biomes. Stream flows are snow-melt dominated and underpinned by groundwater baseflow. The site headwaters contain 37 glaciers and thousands of square kilometers of watersheds in which fire and disease are the only disturbances. In contrast, the HO also contains watersheds at multiple scales that were dominated by glaciers within the last 100 years but are now glacier free, impacted by timber harvests and fires of varying ages to varying degrees, modified by water management practices including irrigation diversion and dams, and altered by development for homes, cities and agriculture. This Observatory provides a sensitive monitor of historic and future climatic shifts, air shed influences and impacts, and the consequences of land and water management practices on the hydrologic system. The HO watersheds are some of the only pristine watersheds left in the contiguous U.S.. They provide critical habitat for key species including the native threaten bull trout and lynx, and the listed western cutthroat trout, bald eagle, gray wolf and the grizzly bear. For the last several thousand years this system has been dominated by snow-melt runoff and moderated by large quantities of water stored in glacial ice. However, the timing and magnitude of droughts and summer flows have changed dramatically. With the information that can be gleaned from sediment cores and landscape records at different scales, this HO provides scientists with opportunities to establish baseline watershed conditions and data on natural hydrologic variability within the system. Such a context frames the current and further observations and assists with translating measured changes into links with the varied HO ecosystems.

Modelling environment contamination with heavy metals in flathead grey mullet Mugil cephalus and upper sediments from north African coasts of the Mediterranean Sea.

PubMed

Ouali, Naouel; Belabed, Bourhane-Eddine; Chenchouni, Haroun

2018-05-18

Heavy metals are a serious hazard for aquatic ecosystems and human health. They negatively affect aquatic life functioning through accumulation resulting physiological/growth disturbances in aquatic lifeforms. This survey focused on the assessment of heavy metal pollution in the Gulf of Annaba (northeastern Algeria), the largest and most diversified industrial hub in Africa, using a multi-compartment approach (water-sediment-biota). The study aims to characterize the spatiotemporal variation of trace metal (TM) contamination and its effects on the growth of the Flathead grey mullet (Mugil cephalus). It reviewed TM concentrations in upper sediments and organs of M. cephalus from various hydrosystems worldwide. Five sites distributed along the Gulf were sampled to determine water physicochemical parameters as well as the contamination of surficial sediments and muscles of M. cephalus by zinc, copper, lead, cadmium and mercury. The spatiotemporal variations of the measured parameters were tested and discussed following the synergetic effects of water, sediment and muscle variables on fish biometrics. The sediments at the Port, Joinoville and Sidi-Salem sites were classified as heavily polluted by lead, copper, zinc and cadmium, whereas only at the Port by mercury. Muscular lead concentrations exceeded international standard values in Joinoville and Port, and zinc in Port. The increase of water dissolved oxygen induced a significant decrease in sediment TM. The increase of sediment TM caused a significant increase in muscle TM levels. The S-shaped logistic models indicated that muscle contaminations reached a saturation plateaus following the current sediment pollution. TM concentrations in fish muscles negatively affected fish weight, but only copper and cadmium significantly influenced fish length. The consumption of fish from the Port, Joinoville and Sidi-Salem can be dangerous because concentrations of lead, zinc and cadmium exceeded the international standards. This study validates the effectiveness of biomonitoring using M. cephalus as bioindicator in polluted coasts. Copyright © 2018 Elsevier B.V. All rights reserved.

Grapevine petioles are more sensitive to drought induced embolism than stems: evidence from in vivo MRI and microcomputed tomography observations of hydraulic vulnerability segmentation.

PubMed

Hochberg, Uri; Albuquerque, Caetano; Rachmilevitch, Shimon; Cochard, Herve; David-Schwartz, Rakefet; Brodersen, Craig R; McElrone, Andrew; Windt, Carel W

2016-09-01

The 'hydraulic vulnerability segmentation' hypothesis predicts that expendable distal organs are more susceptible to water stress-induced embolism than the main stem of the plant. In the current work, we present the first in vivo visualization of this phenomenon. In two separate experiments, using magnetic resonance imaging or synchrotron-based microcomputed tomography, grapevines (Vitis vinifera) were dehydrated while simultaneously scanning the main stems and petioles for the occurrence of emboli at different xylem pressures (Ψx ). Magnetic resonance imaging revealed that 50% of the conductive xylem area of the petioles was embolized at a Ψx of -1.54 MPa, whereas the stems did not reach similar losses until -1.9 MPa. Microcomputed tomography confirmed these findings, showing that approximately half the vessels in the petioles were embolized at a Ψx of -1.6 MPa, whereas only few were embolized in the stems. Petioles were shown to be more resistant to water stress-induced embolism than previously measured with invasive hydraulic methods. The results provide the first direct evidence for the hydraulic vulnerability segmentation hypothesis and highlight its importance in grapevine responses to severe water stress. Additionally, these data suggest that air entry through the petiole into the stem is unlikely in grapevines during drought. © 2015 John Wiley & Sons Ltd.

An Overview of Lipid Droplets in Cancer and Cancer Stem Cells

PubMed Central

Seco, J.

2017-01-01

For decades, lipid droplets have been considered as the main cellular organelles involved in the fat storage, because of their lipid composition. However, in recent years, some new and totally unexpected roles have been discovered for them: (i) they are active sites for synthesis and storage of inflammatory mediators, and (ii) they are key players in cancer cells and tissues, especially in cancer stem cells. In this review, we summarize the main concepts related to the lipid droplet structure and function and their involvement in inflammatory and cancer processes. PMID:28883835

Stem cells in clinical practice: applications and warnings.

PubMed

Lodi, Daniele; Iannitti, Tommaso; Palmieri, Beniamino

2011-01-17

Stem cells are a relevant source of information about cellular differentiation, molecular processes and tissue homeostasis, but also one of the most putative biological tools to treat degenerative diseases. This review focuses on human stem cells clinical and experimental applications. Our aim is to take a correct view of the available stem cell subtypes and their rational use in the medical area, with a specific focus on their therapeutic benefits and side effects. We have reviewed the main clinical trials dividing them basing on their clinical applications, and taking into account the ethical issue associated with the stem cell therapy. We have searched Pubmed/Medline for clinical trials, involving the use of human stem cells, using the key words "stem cells" combined with the key words "transplantation", "pathology", "guidelines", "properties" and "risks". All the relevant clinical trials have been included. The results have been divided into different categories, basing on the way stem cells have been employed in different pathological conditions.

Therapeutic microparticles functionalized with biomimetic cardiac stem cell membranes and secretome

PubMed Central

Tang, Junnan; Shen, Deliang; Caranasos, Thomas George; Wang, Zegen; Vandergriff, Adam C.; Allen, Tyler A.; Hensley, Michael Taylor; Dinh, Phuong-Uyen; Cores, Jhon; Li, Tao-Sheng; Zhang, Jinying; Kan, Quancheng; Cheng, Ke

2017-01-01

Stem cell therapy represents a promising strategy in regenerative medicine. However, cells need to be carefully preserved and processed before usage. In addition, cell transplantation carries immunogenicity and/or tumourigenicity risks. Mounting lines of evidence indicate that stem cells exert their beneficial effects mainly through secretion (of regenerative factors) and membrane-based cell–cell interaction with the injured cells. Here, we fabricate a synthetic cell-mimicking microparticle (CMMP) that recapitulates stem cell functions in tissue repair. CMMPs carry similar secreted proteins and membranes as genuine cardiac stem cells do. In a mouse model of myocardial infarction, injection of CMMPs leads to the preservation of viable myocardium and augmentation of cardiac functions similar to cardiac stem cell therapy. CMMPs (derived from human cells) do not stimulate T-cell infiltration in immuno-competent mice. In conclusion, CMMPs act as ‘synthetic stem cells’ which mimic the paracrine and biointerfacing activities of natural stem cells in therapeutic cardiac regeneration. PMID:28045024

7 CFR 52.1844 - Definition of terms.

Code of Federal Regulations, 2012 CFR

2012-01-01

... branches of the bunch. (b) A piece of stem means a portion of the branch or main stem. (c) Seeds refers to whole, fully developed seeds which have not been removed during the processing of seeded raisins with seeds. (d) Damaged raisins means raisins affected by sunburn, scars, insect injury, mechanical injury...

7 CFR 52.1844 - Definition of terms.

Code of Federal Regulations, 2011 CFR

2011-01-01

... branches of the bunch. (b) A piece of stem means a portion of the branch or main stem. (c) Seeds refers to whole, fully developed seeds which have not been removed during the processing of seeded raisins with seeds. (d) Damaged raisins means raisins affected by sunburn, scars, insect injury, mechanical injury...

Paratachardina pseudolobata (Cocccoidea: Kerriidae): bionomics in Florida

USDA-ARS?s Scientific Manuscript database

Observations on the bionomics of lobate lac scale, Paratachardina pseudolobata Kondo & Gullan in Florida are reported. Lobate lac scale infests primarily the branches and main stems of <2 cm in dia; rarely were they found on stems larger than 4 cm in dia or on leaves and never on roots. They produce...

The Porter Stemming Algorithm: Then and Now

ERIC Educational Resources Information Center

Willett, Peter

2006-01-01

Purpose: In 1980, Porter presented a simple algorithm for stemming English language words. This paper summarises the main features of the algorithm, and highlights its role not just in modern information retrieval research, but also in a range of related subject domains. Design/methodology/approach: Review of literature and research involving use…

Expression of novel, putative stem cell markers in prepubertal and lactating mammary glands of bovine

USDA-ARS?s Scientific Manuscript database

Mammary stem cells (MaSC) are essential for growth and maintenance of the mammary epithelium. Two main phases of mammary growth include ductal elongation prior to puberty and lobulo-alveolar growth and development during pregnancy. Some studies have utilized morphological characteristics and retenti...

Differences in students' perceived classroom experiences by instructor gender, student gender, and persistence in STEM courses

NASA Astrophysics Data System (ADS)

Fowlkes, Carol

Science, technology, engineering, and mathematics (STEM) fields are growing and have lucrative job opportunities for college graduates. However, the number of students in STEM majors and the number of those who persist in those majors is declining; there is also a growing gender gap in STEM graduates. This study investigated three perceived classroom experiences in STEM courses and the nature of differences in these experiences by student gender, instructor gender, and by those who persisted or did not persist in STEM majors. A factorial MANOVA was the statistical method by which the differences were explored. The statistical analysis revealed non-significant mean differences in three-way interaction, all two-way interactions, and all main effects. There were not gendered differences in students' perceptions of the opportunities for hands-on learning, the instructor cares about students' success, and the instructor encourages students' contributions. Further research is proposed to continue examination of this topic with a larger data set that is consistent with the literature regarding the population of STEM students and the number of STEM persisters, and the male-gendered nature of STEM fields.

Therapeutic application of stem cells in gastroenterology: an up-date.

PubMed

Burra, Patrizia; Bizzaro, Debora; Ciccocioppo, Rachele; Marra, Fabio; Piscaglia, Anna Chiara; Porretti, Laura; Gasbarrini, Antonio; Russo, Francesco Paolo

2011-09-14

Adult stem cells represent the self-renewing progenitors of numerous body tissues, and they are currently classified according to their origin and differentiation ability. In recent years, the research on stem cells has expanded enormously and holds therapeutic promises for many patients suffering from currently disabling diseases. This paper focuses on the possible use of stem cells in the two main clinical settings in gastroenterology, i.e., hepatic and intestinal diseases, which have a strong impact on public health worldwide. Despite encouraging results obtained in both regenerative medicine and immune-mediated conditions, further studies are needed to fully understand the biology of stem cells and carefully assess their putative oncogenic properties. Moreover, the research on stem cells arouses fervent ethical, social and political debate. The Italian Society of Gastroenterology sponsored a workshop on stem cells held in Verona during the XVI Congress of the Federation of Italian Societies of Digestive Diseases (March 6-9, 2010). Here, we report on the issues discussed, including liver and intestinal diseases that may benefit from stem cell therapy, the biology of hepatic and intestinal tissue repair, and stem cell usage in clinical trials.

Composition and antioxidant activity of the essential oils of Xylopia aethiopica (Dun) A. Rich. (Annonaceae) leaves, stem bark, root bark, and fresh and dried fruits, growing in Ghana.

PubMed

Karioti, Anastasia; Hadjipavlou-Litina, Dimitra; Mensah, Merlin L K; Fleischer, Theophilus C; Skaltsa, Helen

2004-12-29

The chemical composition of the essential oils obtained from the leaves, the barks of the stem and the root, as well as from the fresh and dried fruits of Xylopia aethiopica, growing in Ghana, was investigated by gas chromatography/mass spectrometry analyses. Kovats indices, mass spectra, and standard compounds were used to identify a total of 93 individual compounds. The monoterpene hydrocarbons formed the main portion in all studied samples. beta-Pinene was predominant in all cases, while trans-m-mentha-1(7),8-diene was the main compound in the essential oils of the leaves and the barks of roots and stems. Their potential antioxidant activity was also investigated and found to be significant in scavenging superoxide anion radical.

The technology of obtaining multipotent spheroids from limbal mesenchymal stromal cells for reparation of injured eye tissues.

PubMed

Kosheleva, N V; Saburina, I N; Zurina, I M; Gorkun, A A; Borzenok, S A; Nikishin, D A; Kolokoltsova, T D; Ustinova, E E; Repin, V S

2016-01-01

It is known that stem and progenitor cells open new possibilities for restoring injured eye tissues. Limbal eye zone, formed mainly by derivatives of neural crest, is the main source of stem cells for regeneration. The current study considers development of innovative technology for obtaining 3D spheroids from L-MMSC. It was shown that under 3D conditions L-MMSC due to compactization and mesenchymal-epithelial transition self-organize into cellular reparative modules. Formed L-MMSC spheroids retain and promote undifferentiated population of stem and progenitor limbal cells, as supported by expression of pluripotency markers - Oct4, Sox2, Nanog. Extracellular matrix synthetized by cells in spheroids allows retaining the functional potential of L-MMSC that are involved in regeneration of both anterior and, probably, posterior eye segment.

The Core of Sibling Stem Cell Donation – A Grounded Theory Study

PubMed Central

Kisch, Annika M; Forsberg, Anna

2017-01-01

Background: There is a lack of theoretical framework supporting stem cell transplant nurses in their assessment, judgment and caring interventions of sibling stem cell donors. Objective: The purpose of this study was to explore sibling stem cell donors’ main concerns and how they deal with them before and after donation. Method: Ten healthy sibling donors, 5 men and 5 women, with a median age of 54 years were included in this study when they were due to donate stem cells to a brother or sister. Data were collected prospectively on three occasions (before the donation and three and twelve months after it) through in-depth interviews, which were recorded and transcribed verbatim for analysis by the Grounded Theory method according to Charmaz. Results: This study describes the efforts of the ten donors to fulfil their duty as a sibling by doing what they considered necessary in order to help. Their efforts were summarised in a process wherein the grounded theory generated three main categories; Prepare, Promote and Preserve. A clear path of transition leading to fulfilment is evident, starting before the donation and continuing for one year afterwards. Conclusions: Being a sibling stem cell donor means doing what you have to do to fulfil your duty and if possible, saving the life of a seriously ill brother or sister. The relationship between the siblings is strengthened by the donation process. Sibling stem cell donation appears to be about fulfilment and the theoretical framework may support clinicians in their evaluation and support of donors. PMID:28839511

Sources and transport of algae and nutrients in a Californian river in a semi-arid climate

USGS Publications Warehouse

Ohte, N.; Dahlgren, R.A.; Silva, S.R.; Kendall, C.; Kratzer, C.R.; Doctor, D.H.

2007-01-01

1. To elucidate factors contributing to dissolved oxygen (DO) depletion in the Stockton Deep Water Ship Channel in the lower San Joaquin River, spatial and temporal changes in algae and nutrient concentrations were investigated in relation to flow regime under the semiarid climate conditions. 2. Chlorophyll-a (chl-a) concentration and loads indicated that most algal biomass was generated by in-stream growth in the main stem of the river. The addition of algae from tributaries and drains was small (c.15% of total chl-a load), even though high concentrations of chl-a were measured in some source waters. 3. Nitrate and soluble-reactive phosphorus (SRP) were available in excess as a nutrient source for algae. Although nitrate and SRP from upstream tributaries contributed (16.9% of total nitrate load and 10.8% of total SRP load), nutrients derived from agriculture and other sources in the middle and lower river reaches were mostly responsible (20.2% for nitrate and 48.0% for SRP) for maintaining high nitrate and SRP concentrations in the main stem. 4. A reduction in nutrient discharge would attenuate the algal blooms that accelerate DO depletion in the Stockton Deep Water Ship Channel. The N : P ratio, in the main stem suggests that SRP reduction would be a more viable option for algae reduction than nitrogen reduction. 5. Very high algal growth rates in the main stem suggest that reducing the algal seed source in upstream areas would also be an effective strategy. ?? 2007 Blackwell Publishing Ltd.

A Research Experience for Undergraduates on Sustainable Land and Water Resources

NASA Astrophysics Data System (ADS)

Dalbotten, D. M.; Berthelote, A. R.; Myrbo, A.; Ito, E.; Howes, T.

2011-12-01

A new research experience for undergraduates is being piloted which supports student involvement in management of land and water resources with sustainability as the major focus. Working on two Native American reservations (Fond du Lac Band of Lake Superior Chippewa, and Confederated Salish and Kootenai Tribes of Flathead Reservation) and in conjunction with local tribal colleges, we particularly focus on management of tribal land and water resources. In this way we work to both increase the involvement of Native American students in the geosciences and support ethical partnerships for research on Native lands. Students also have the opportunity to work experimentally at the St. Anthony Falls Laboratory in conjunction with the National Center for Earth-surface Dynamics.

A reconnaissance study of halogenated organic compounds in catfish from the lower Mississippi river and its major tributaries

USGS Publications Warehouse

Leiker, T.J.; Rostad, C.E.; Barnes, C.R.; Pereira, W.E.

1991-01-01

Blue catfish, (Ictarurus furcatus), black bullhead catfish, (Ictalurus melas), channel catfish (Ictalurus punctatus), and flathead catfish (Pylodictus olivaris), were collected along a 1200 mile river reach of the Mississippi River and its major tributaries. Tissue samples were extracted and analyzed by fused silica capillary gas chromatography/mass spectrometry (GC/MS) to determine the concentrations of hydrophobic organic halogenated contaminants that have bioconcentrated within the tissues. The compounds identified in the tissue include chlordane, polychlorinated biphenyls (PCBs), DDT and its metabolites along with several other chlorinated pesticides. The data indicates that the southern reach of the river system appears to be more contaminated than the middle and upper reaches of the study area.

Wildlife Loss Estimates and Summary of Previous Mitigation Related to Hydroelectric Projects in Montana, Volume Three, Hungry Horse Project.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Casey, Daniel

1984-10-01

This assessment addresses the impacts to the wildlife populations and wildlife habitats due to the Hungry Horse Dam project on the South Fork of the Flathead River and previous mitigation of theses losses. In order to develop and focus mitigation efforts, it was first necessary to estimate wildlife and wildlife hatitat losses attributable to the construction and operation of the project. The purpose of this report was to document the best available information concerning the degree of impacts to target wildlife species. Indirect benefits to wildlife species not listed will be identified during the development of alternative mitigation measures. Wildlifemore » species incurring positive impacts attributable to the project were identified.« less

The regulatory sciences for stem cell-based medicinal products.

PubMed

Yuan, Bao-Zhu; Wang, Junzhi

2014-06-01

Over the past few years, several new achievements have been made from stem cell studies, many of which have moved up from preclinical stages to early, or from early to middle or late, stages thanks to relatively safe profile and preliminary evidence of effectiveness. Moreover, some stem cell-based products have been approved for marketing by different national regulatory authorities. However, many critical issues associated mainly with incomplete understanding of stem cell biology and the relevant risk factors, and lack of effective regulations still exist and need to be urgently addressed, especially in countries where establishment of appropriate regulatory system just commenced. More relevantly, the stem cell regulatory sciences need to be established or improved to more effectively evaluate quality, safety and efficacy of stem cell products, and for building up the appropriate regulatory framework. In this review, we summarize some new achievements in stem cell studies, especially the preclinical and clinical studies, the existing regulations, and the associated challenges, and we then propose some considerations for improving stem cell regulatory sciences with a goal of promoting the steadfast growth of the well-regulated stem cell therapies abreast of evolvement of stem cell sciences and technologies.

BRANCH JUNCTIONS AND THE FLOW OF WATER THROUGH XYLEM IN DOUGLAS-FIR AND PONDEROSA PINE STEMS

EPA Science Inventory

Water flowing through the xylem of most plants from the roots to the leaves must pass through junctions where branches have developed from the main stem. These junctions have been studied as both flow constrictions and components of a hydraulic segmentation mechanism to protect ...

A Computer-Based Simulation for Teaching Heat Transfer across a Woody Stem

ERIC Educational Resources Information Center

Maixner, Michael R.; Noyd, Robert K.; Krueger, Jerome A.

2010-01-01

To assist student understanding of heat transfer through woody stems, we developed an instructional package that included an Excel-based, one-dimensional simulation model and a companion instructional worksheet. Guiding undergraduate botany students to applying principles of thermodynamics to plants in nature is fraught with two main obstacles:…

Exploring Teacher Design Team Endeavors While Creating an Elementary-Focused STEM-Integrated Curriculum

ERIC Educational Resources Information Center

McFadden, Justin R.; Roehrig, Gillian H.

2017-01-01

Background: This study presents two teacher design teams (TDTs) during a professional development experience centered on science, technology, engineering, and mathematics (STEM)-integrated curriculum development. The main activity of the study, curriculum design, was framed as a design problem in order to better understand how teachers engaged…

Scotblood 2007: Tackling local and global issues in transfusion medicine - donor recruitment, effective use of blood, stem cell plasticity, and vCJD.

PubMed

Bessos, Hagop; Fraser, Robin; Seghatchian, Jerard

2008-02-01

This commentary briefly highlights some of the local and the global contemporary issues affecting transfusion medicine worldwide. The main areas of focus addressed this year were: donor recruitment, stem cell plasticity, the effective use of blood, and vCJD.

Applied Induced Pluripotent Stem Cells in Combination With Biomaterials in Bone Tissue Engineering.

PubMed

Ardeshirylajimi, Abdolreza

2017-10-01

Due to increasing of the orthopedic lesions and fractures in the world and limitation of current treatment methods, researchers, and surgeons paid attention to the new treatment ways especially to tissue engineering and regenerative medicine. Innovation in stem cells and biomaterials accelerate during the last decade as two main important parts of the tissue engineering. Recently, induced pluripotent stem cells (iPSCs) introduced as cells with highly proliferation and differentiation potentials that hold great promising features for used in tissue engineering and regenerative medicine. As another main part of tissue engineering, synthetic, and natural polymers have been shown daily grow up in number to increase and improve the grade of biopolymers that could be used as scaffold with or without stem cells for implantation. One of the developed areas of tissue engineering is bone tissue engineering; the aim of this review is present studies were done in the field of bone tissue engineering while used iPSCs in combination with natural and synthetic biomaterials. J. Cell. Biochem. 118: 3034-3042, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Purification, characterization and immunomodulatory activity of polysaccharides from stem lettuce.

PubMed

Nie, Chenzhipeng; Zhu, Peilei; Ma, Shuping; Wang, Mingchun; Hu, Youdong

2018-05-15

Stem lettuce has a long history of cultivation in China and possesses high nutritional and medicinal value. In our previous studies, extraction optimization, characterization, and bioactivities of stem lettuce polysaccharides (SLP) were investigated. In this study, SLP were further separated into two purified polysaccharides, SLP-1 and SLP-2, by anion exchange chromatography followed by size exclusion chromatography. SLP-1, with a molecular weight of 90 KDa, was mainly composed of galacturonic acid, galactose and arabinose in a molar ratio of 17.6:41.7:33.9. SLP-2, with a molecular weight of 44 KDa, was mainly composed of mannose, galacturonic acid, galactose and arabinose in a molar ratio of 11.5:69.5:9.3:8.2. In addition, both purified polysaccharides contain sulphate radicals, have triple helical structures and can promote macrophage proliferation without cytotoxicity. SLP-2 was better able to stimulate phagocytic and nitric oxide production than SLP-1. The results suggest that polysaccharides from stem lettuce could be explored as immunomodulatory agents in the field of pharmaceuticals and functional foods. Copyright © 2018 Elsevier Ltd. All rights reserved.

Investigation of cell wall composition related to stem lodging resistance in wheat (Triticum aestivum L.) by FTIR spectroscopy.

PubMed

Wang, Jian; Zhu, Jinmao; Huang, RuZhu; Yang, YuSheng

2012-07-01

We explored the rapid qualitative analysis of wheat cultivars with good lodging resistances by Fourier transform infrared resonance (FTIR) spectroscopy and multivariate statistical analysis. FTIR imaging showing that wheat stem cell walls were mainly composed of cellulose, pectin, protein, and lignin. Principal components analysis (PCA) was used to eliminate multicollinearity among multiple peak absorptions. PCA revealed the developmental internodes of wheat stems could be distributed from low to high along the load of the second principal component, which was consistent with the corresponding bands of cellulose in the FTIR spectra of the cell walls. Furthermore, four distinct stem populations could also be identified by spectral features related to their corresponding mechanical properties via PCA and cluster analysis. Histochemical staining of four types of wheat stems with various abilities to resist lodging revealed that cellulose contributed more than lignin to the ability to resist lodging. These results strongly suggested that the main cell wall component responsible for these differences was cellulose. Therefore, the combination of multivariate analysis and FTIR could rapidly screen wheat cultivars with good lodging resistance. Furthermore, the application of these methods to a much wider range of cultivars of unknown mechanical properties promises to be of interest.

Stem Cells for Osteochondral Regeneration.

PubMed

Canadas, Raphaël F; Pirraco, Rogério P; Oliveira, J Miguel; Reis, Rui L; Marques, Alexandra P

2018-01-01

Stem cell research plays a central role in the future of medicine, which is mainly dependent on the advances on regenerative medicine (RM), specifically in the disciplines of tissue engineering (TE) and cellular therapeutics. All RM strategies depend upon the harnessing, stimulation, or guidance of endogenous developmental or repair processes in which cells have an important role. Among the most clinically challenging disorders, cartilage degeneration, which also affects subchondral bone becoming an osteochondral (OC) defect, is one of the most demanding. Although primary cells have been clinically applied, stem cells are currently seen as the promising tool of RM-related research because of its availability, in vitro proliferation ability, pluri- or multipotency, and immunosuppressive features. Being the OC unit, a transition from the bone to cartilage, mesenchymal stem cells (MSCs) are the main focus for OC regeneration. Promising alternatives, which can also be obtained from the patient or at banks and have great differentiation potential toward a wide range of specific cell types, have been reported. Still, ethical concerns and tumorigenic risk are currently under discussion and assessment. In this book chapter, we revise the existing stem cell-based approaches for engineering bone and cartilage, focusing on cell therapy and TE. Furthermore, 3D OC composites based on cell co-cultures are described. Finally, future directions and challenges still to be faced are critically discussed.

Evaluating the conservation potential of tributaries for native fishes in the Upper Colorado River Basin

USGS Publications Warehouse

Laub, Brian G.; Thiede, Gary P.; Macfarlane, William W.; Budy, Phaedra

2018-01-01

We explored the conservation potential of tributaries in the upper Colorado River basin by modeling native fish species richness as a function of river discharge, temperature, barrier‐free length, and distance to nearest free‐flowing main‐stem section. We investigated a historic period prior to large‐scale water development and a contemporary period. In the historic period, species richness was log‐linearly correlated to variables capturing flow magnitude, particularly mean annual discharge. In the contemporary period, the log‐linear relationship between discharge and species richness was still evident but weaker. Tributaries with lower average temperature and separated from free‐flowing main‐stem sections often had fewer native species compared to tributaries with similar discharge but with warmer temperature and directly connected to free‐flowing main stems. Thus, tributaries containing only a small proportion of main‐stem discharge, especially those at lower elevations with warmer temperatures and connected to free‐flowing main stems, can support a relatively high species richness. Tributaries can help maintain viable populations by providing ecological processes disrupted on large regulated rivers, such as natural flow and temperature regimes, and may present unique conservation opportunities. Efforts to improve fish passage, secure environmental flows, and restore habitat in these tributaries could greatly contribute to conservation of native fish richness throughout the watershed.

Effect of calcium sprays on mechanical strength and cell wall fractions of herbaceous peony (Paeonia lactiflora pall.) inflorescence stems.

PubMed

Li, Chengzhong; Tao, Jun; Zhao, Daqiu; You, Chao; Ge, Jintao

2012-01-01

Calcium is an essential element and imparts significant structural rigidity to the plant cell walls, which provide the main mechanical support to the entire plant. In order to increase the mechanical strength of the inflorescence stems of herbaceous peony, the stems are treated with calcium chloride. The results shows that preharvest sprays with 4% (w/v) calcium chloride three times after bud emergence are the best at strengthening "Da Fugui" peonies' stems. Calcium sprays increased the concentrations of endogenous calcium, total pectin content as well as cell wall fractions in herbaceous peonies stems, and significantly increased the contents of them in the top segment. Correlation analysis showed that the breaking force of the top segment of peonies' stems was positively correlated with the ratio of water insoluble pectin to water soluble pectin (R = 0.673) as well as lignin contents (R = 0.926) after calcium applications.

Stem Cells Transplantation in the Treatment of Patients with Liver Failure.

PubMed

Tao, Ya-Chao; Wang, Meng-Lan; Chen, En-Qiang; Tang, Hong

2018-02-23

Liver failure is a life-threatening liver disease encompassing severe acute deterioration of liver function. Emergency liver transplantation is the only curative treatment for liver failure, but is restricted by the severe shortage of organ donors. Stem cell, including embroyonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, hematopoietic stem cells and hepatic progenitor cells, have capacity to proliferate and differentiate and could be used in a variety of liver diseases including hereditary liver diseases, cirrhosis and liver failure. We summarized the basic experimental and clinical advances of stem cell transplantation in liver failure treatment, and also discussed the advantages and disadvantage of different stem cells subtype in this field, aiming to provide a perspective on the stem cell-based therapy for liver failure. Stem cells, especially mesenchymal stem cells (mainly low immunogenicity and paracrine characteristics) and induced pluripotent stem cells (generation of desired cell type from somatic cell), are feasible candidates for cell therapy in the treatment of liver failure, but there are some drawbacks remaining to be resolved, such as low engraftment, cryotpreservation methods and tumorigenesis. Stem cell transplantation is a promising but challenging strategy and paves a new way for curing liver failure. But more efforts need to be made to overcome problems before this new strategy could be safely and effectively applied to humans. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Shoot development in grapevine (Vitis vinifera) is affected by the modular branching pattern of the stem and intra- and inter-shoot trophic competition.

PubMed

Lebon, Eric; Pellegrino, Anne; Tardieu, Francois; Lecoeur, Jeremie

2004-03-01

Shoot architecture variability in grapevine (Vitis vinifera) was analysed using a generic modelling approach based on thermal time developed for annual herbaceous species. The analysis of shoot architecture was based on various levels of shoot organization, including pre-existing and newly formed parts of the stem, and on the modular structure of the stem, which consists of a repeated succession of three phytomers (P0-P1-P2). Four experiments were carried out using the cultivar 'Grenache N': two on potted vines (one of which was carried out in a glasshouse) and two on mature vines in a vineyard. These experiments resulted in a broad diversity of environmental conditions, but none of the plants experienced soil water deficit. Development of the main axis was highly dependent on air temperature, being linearly related to thermal time for all stages of leaf development from budbreak to veraison. The stable progression of developmental stages along the main stem resulted in a thermal-time based programme of leaf development. Leaf expansion rate varied with trophic competition (shoot and cluster loads) and environmental conditions (solar radiation, VPD), accounting for differences in final leaf area. Branching pattern was highly variable. Classification of the branches according to ternary modular structure increased the accuracy of the quantitative analysis of branch development. The rate and duration of leaf production were higher for branches derived from P0 phytomers than for branches derived from P1 or P2 phytomers. Rates of leaf production, expressed as a -function of thermal time, were not stable and depended on trophic competition and environmental conditions such as solar radiation or VPD. The application to grapevine of a generic model developed in annual plants made it possible to identify constants in main stem development and to determine the hierarchical structure of branches with respect to the modular structure of the stem in response to intra- and inter-shoot trophic competition.

Stem Cell-Based Therapies for Polyglutamine Diseases.

PubMed

Mendonça, Liliana S; Onofre, Isabel; Miranda, Catarina Oliveira; Perfeito, Rita; Nóbrega, Clévio; de Almeida, Luís Pereira

2018-01-01

Polyglutamine (polyQ) diseases are a family of neurodegenerative disorders with very heterogeneous clinical presentations, although with common features such as progressive neuronal death. Thus, at the time of diagnosis patients might present an extensive and irreversible neuronal death demanding cell replacement or support provided by cell-based therapies. For this purpose stem cells, which include diverse populations ranging from embryonic stem cells (ESCs), to fetal stem cells, mesenchymal stromal cells (MSCs) or induced pluripotent stem cells (iPSCs) have remarkable potential to promote extensive brain regeneration and recovery in neurodegenerative disorders. This regenerative potential has been demonstrated in exciting pre and clinical assays. However, despite these promising results, several drawbacks are hampering their successful clinical implementation. Problems related to ethical issues, quality control of the cells used and the lack of reliable models for the efficacy assessment of human stem cells. In this chapter the main advantages and disadvantages of the available sources of stem cells as well as their efficacy and potential to improve disease outcomes are discussed.

[Effect of different organic fertilizers on bioavailability of soil Cd and Zn].

PubMed

Xie, Yun-he; Ji, Xiong-hui; Wu, Jia-mei; Huang, Juan; Guan, Di; Zhu, Jian

2015-03-01

The active effect of soil Cd and Zn and their interaction was studied in typical paddy field in south China by monitoring the contents of Cd and Zn in soil and rice in rice fields applied with pig manure, chicken manure or rice straw for 4 years continuously. The results showed that applying pig manure, chicken manure or rice straw had no significant impact on the soil total Cd content, soil available Cd content and soil Cd activity, but tended to increase the soil total Cd content and increased the soil total Zn content, soil available Zn content and Zn activity significantly. Applications of pig manure, chicken manure and rice straw all reduced the Cd content of brown rice, in order of pig manure > chicken manure > rice straw. The Cd contents of brown rice, stem and leaf in the treatment applied with pig manure were lower than in the control by 37.5%, 44.0% and 36.4%, respectively; the Cd contents of brown rice, stem and leaf in the treatment applied with chicken manure were lower than in the control by 22.5%, 33.8%, and 22.7%, respectively; the Cd content of brown rice in the treatment applied with rice straw was lower than in the control by 7.5% but its contents in stem and leaf increased by 8.2% and 22.7% , respectively. The reduction in the brown rice Cd content was mainly due to the reduction of Cd enrichment from soil to brown rice after application of pig or chicken manure, but mainly due to the reduction of Cd transportation from stem to brown rice after straw application. Applications of pig manure, chicken manure and rice straw increased Zn contents in rice stem by 53.4%, 53.4% and 13.9%, respectively, but all had no significant effect on brown rice and leaf' s Zn contents. Zn and Cd had the significant antagonistic effects in the soil and rice stem. The increase of Zn content in soil and rice stem inhibited the adsorption and accumulation of Cd in the brown rice, stem and leaf significantly, and with the increase of the proportion of Zn/Cd, the competitive absorption between Cd and Zn by rice was the main control factor affecting the Cd absorption by rice than their competitive adsorption by soil.

Cellular sequestration of cadmium in the hyperaccumulator plant species Sedum alfredii.

PubMed

Tian, Shengke; Lu, Lingli; Labavitch, John; Yang, Xiaoe; He, Zhenli; Hu, Hening; Sarangi, Ritimukta; Newville, Matt; Commisso, Joel; Brown, Patrick

2011-12-01

Spatial imaging of cadmium (Cd) in the hyperaccumulator Sedum alfredii was investigated in vivo by laser ablation inductively coupled plasma mass spectrometry and x-ray microfluorescence imaging. Preferential Cd accumulation in the pith and cortex was observed in stems of the Cd hyperaccumulating ecotype (HE), whereas Cd was restricted to the vascular bundles in its contrasting nonhyperaccumulating ecotype. Cd concentrations of up to 15,000 μg g(-1) were measured in the pith cells, which was many fold higher than the concentrations in the stem epidermis and vascular bundles in the HE plants. In the leaves of the HE, Cd was mainly localized to the mesophyll and vascular cells rather than the epidermis. The distribution pattern of Cd in both stems and leaves of the HE was very similar to calcium but not zinc, irrespective of Cd exposure levels. Extended x-ray absorption fine structure spectroscopy analysis showed that Cd in the stems and leaves of the HE was mainly associated with oxygen ligands, and a larger proportion (about 70% in leaves and 47% in stems) of Cd was bound with malic acid, which was the major organic acid in the shoots of the plants. These results indicate that a majority of Cd in HE accumulates in the parenchyma cells, especially in stems, and is likely associated with calcium pathways and bound with organic acid (malate), which is indicative of a critical role of vacuolar sequestration of Cd in the HE S. alfredii.

Anticarcinogenic activity of polyphenolic extracts from grape stems against breast, colon, renal and thyroid cancer cells.

PubMed

Sahpazidou, Despina; Geromichalos, George D; Stagos, Dimitrios; Apostolou, Anna; Haroutounian, Serkos A; Tsatsakis, Aristidis M; Tzanakakis, George N; Hayes, A Wallace; Kouretas, Dimitrios

2014-10-15

A major part of the wineries' wastes is composed of grape stems which are discarded mainly in open fields and cause environmental problems due mainly to their high polyphenolic content. The grape stem extracts' use as a source of high added value polyphenols presents great interest because this combines a profitable venture with environmental protection close to wine-producing zones. In the present study, at first, the Total Polyphenolic Content (TPC) and the polyphenolic composition of grape stem extracts from four different Greek Vitis vinifera varieties were determined by HPLC methods. Afterwards, the grape stem extracts were examined for their ability to inhibit growth of colon (HT29), breast (MCF-7 and MDA-MB-23), renal (786-0 and Caki-1) and thyroid (K1) cancer cells. The cancer cells were exposed to the extracts for 72 h and the effects on cell growth were evaluated using the SRB assay. The results indicated that all extracts inhibited cell proliferation, with IC₅₀ values of 121-230 μg/ml (MCF-7), 121-184 μg/ml (MDA-MD-23), 175-309 μg/ml (HT29), 159-314 μg/ml (K1), 180-225 μg/ml (786-0) and 134->400 μg/ml (Caki-1). This is the first study presenting the inhibitory activity of grape stem extracts against growth of colon, breast, renal and thyroid cancer cells. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

A Survey of Italian Physicians' Opinion about Stem Cells Research: What Doctors Prefer and What the Law Requires

PubMed Central

Frati, Paola; Pacchiarotti, Arianna; D'Errico, Stefano

2014-01-01

To evaluate the Italian physicians' knowledge/information level about the therapeutic potential of stem cells, the research choice between embryonic and cordonal stem cells, and the preference between autologous and heterologous storage of cordonal stem cells, we performed a national survey. The questionnaire—distributed to 3361 physicians—involved physicians of different religious orientations and of different medical specialities. Most of the physicians involved (67%) were Catholics, and the majority were gynaecologists and paediatricians (43%) who are mainly in charge to inform future mothers about the possibility of cordonal stem cells conservation. The majority of the physicians interviewed do not have specific knowledge about stem cells (59%), most of them having only generic information (92%). The largest part of physicians prefer to use umbilical cord blood cells rather than embryonic stem cells. Nevertheless, a large percentage of physicians were in favour of embryo research, especially when embryos are supernumerary (44% versus 34%). Eighty-seven % of the physicians interviewed proved to have a general knowledge about stem cells and believe in their therapeutic potential. They prefer research on cordonal stem cells rather than on embryo stem cells. Although they are in favour of heterologous stem cells donation, they still prefer cryopreservation for personal use. PMID:24877099

Advances in translational inner ear stem cell research.

PubMed

Warnecke, Athanasia; Mellott, Adam J; Römer, Ariane; Lenarz, Thomas; Staecker, Hinrich

2017-09-01

Stem cell research is expanding our understanding of developmental biology as well as promising the development of new therapies for a range of different diseases. Within hearing research, the use of stem cells has focused mainly on cell replacement. Stem cells however have a broad range of other potential applications that are just beginning to be explored in the ear. Mesenchymal stem cells are an adult derived stem cell population that have been shown to produce growth factors, modulate the immune system and can differentiate into a wide variety of tissue types. Potential advantages of mesenchymal/adult stem cells are that they have no ethical constraints on their use. However, appropriate regulatory oversight seems necessary in order to protect patients from side effects. Disadvantages may be the lack of efficacy in many preclinical studies. But if proven safe and efficacious, they are easily translatable to clinical trials. The current review will focus on the potential application on mesenchymal stem cells for the treatment of inner ear disorders. Copyright © 2017 Elsevier B.V. All rights reserved.

Are there endogenous stem cells in the spinal cord?

PubMed

Ferrucci, Michela; Ryskalin, Larisa; Busceti, Carla L; Gaglione, Anderson; Biagioni, Francesca; Fornai, Francesco

2017-12-01

Neural progenitor cells (NPC) represent the stem-like niche of the central nervous system that maintains a regenerative potential also in the adult life. Despite NPC in the brain are well documented, the presence of NPC in the spinal cord has been controversial for a long time. This is due to a scarce activity of NPC within spinal cord, which also makes difficult their identification. The present review recapitulates the main experimental studies, which provided evidence for the occurrence of NPC within spinal cord, with a special emphasis on spinal cord injury and amyotrophic lateral sclerosis. By using experimental models, here we analyse the site-specificity, the phenotype and the main triggers of spinal cord NPC. Moreover, data are reported on the effect of specific neurogenic stimuli on these spinal cord NPC in an effort to comprehend the endogenous neurogenic potential of this stem cell niche.

A Study of Creativity in CaC[subscript 2] Steamship-Derived STEM Project-Based Learning

ERIC Educational Resources Information Center

Lou, Shi-Jer; Chou, Yung-Chieh; Shih, Ru-Chu; Chung, Chih-Chao

2017-01-01

This study mainly aimed to explore the effects of project-based learning (PBL) integrated into science, technology, engineering and mathematics (STEM) activities and to analyze the creativity displayed by junior high school students while performing these activities. With a quasi-experimental design, 60 ninth-grade students from a junior high…

The NSL chromatin-modifying complex subunit KANSL2 regulates cancer stem-like properties in glioblastoma that contribute to tumorigenesis

PubMed Central

Ferreyra-Solari, Nazarena; Belforte, Fiorella S.; Canedo, Lucía; Videla-Richardson, Guillermo A.; Espinosa, Joaquín M.; Rossi, Mario; Serna, Eva; Riudavets, Miguel A.; Martinetto, Horacio; Sevlever, Gustavo; Perez-Castro, Carolina

2016-01-01

KANSL2 is an integral subunit of the Non-Specific Lethal (NSL) chromatin-modifying complex which contributes to epigenetic programs in embryonic stem cells. In this study, we report a role for KANSL2 in regulation of stemness in glioblastoma (GBM), which is characterized by heterogeneous tumor stem-like cells associated with therapy resistance and disease relapse. KANSL2 expression is upregulated in cancer cells, mainly at perivascular regions of tumors. RNAi-mediated silencing of KANSL2 in GBM cells impairs their tumorigenic capacity in mouse xenograft models. In clinical specimens, we found that expression levels of KANSL2 correlate with stemness markers in GBM stem-like cell populations. Mechanistic investigations showed that KANSL2 regulates cell self-renewal, which correlates with effects on expression of the stemness transcription factor POU5F1. RNAi-mediated silencing of POU5F1 reduced KANSL2 levels, linking these two genes to stemness control in GBM cells. Together, our findings indicate that KANSL2 acts to regulate the stem cell population in GBM, defining it as a candidate GBM biomarker for clinical use. PMID:27406830

Therapeutic application of stem cells in gastroenterology: An up-date

PubMed Central

Burra, Patrizia; Bizzaro, Debora; Ciccocioppo, Rachele; Marra, Fabio; Piscaglia, Anna Chiara; Porretti, Laura; Gasbarrini, Antonio; Russo, Francesco Paolo

2011-01-01

Adult stem cells represent the self-renewing progenitors of numerous body tissues, and they are currently classified according to their origin and differentiation ability. In recent years, the research on stem cells has expanded enormously and holds therapeutic promises for many patients suffering from currently disabling diseases. This paper focuses on the possible use of stem cells in the two main clinical settings in gastroenterology, i.e., hepatic and intestinal diseases, which have a strong impact on public health worldwide. Despite encouraging results obtained in both regenerative medicine and immune-mediated conditions, further studies are needed to fully understand the biology of stem cells and carefully assess their putative oncogenic properties. Moreover, the research on stem cells arouses fervent ethical, social and political debate. The Italian Society of Gastroenterology sponsored a workshop on stem cells held in Verona during the XVI Congress of the Federation of Italian Societies of Digestive Diseases (March 6-9, 2010). Here, we report on the issues discussed, including liver and intestinal diseases that may benefit from stem cell therapy, the biology of hepatic and intestinal tissue repair, and stem cell usage in clinical trials. PMID:22025875

Predicting the decomposition of Scots pine, Norway spruce, and birch stems in Finland.

PubMed

Mäkinen, Harri; Hynynen, Jari; Siitonen, Juha; Sievänen, Risto

2006-10-01

Models were developed for predicting the decomposition of dead wood for the main tree species in Finland, based on data collected from long-term thinning experiments in southern and central Finland. The decomposition rates were strongly related to the number of years after tree death. In contrast to previous studies, which have used the first-order exponential model, we found that the decomposition rate was not constant. Therefore, the Gompertz and Chapman-Richard's functions were fitted to the data. The slow initial decomposition period was mainly due to the fact that most dead trees remained standing as snags after their death. The initial period was followed by a period of rapid decomposition and, finally, by a period of moderately slow decomposition. Birch stems decomposed more rapidly than Scots pine and Norway spruce stems. Decomposition rates of Norway spruce stems were somewhat lower than those of Scots pine. Because the carbon concentration of decaying boles was relatively stable (about 50%) the rate of carbon loss follows that of mass loss. Models were also developed for the probability that a dead tree remains standing as a snag. During the first years after death, the probability was high. Thereafter, it decreased rapidly, the decrease being faster for birch stems than for Scots pine and Norway spruce stems. Almost all stems had fallen down within 40 years after their death. In Scots pine and Norway spruce, most snags remained hard and belonged to decay class 1. In birch, a higher proportion of snags belonged to the more advanced decay classes. The models provide a framework for predicting dead wood dynamics in managed as well as dense unthinned stands. The models can be incorporated into forest management planning systems, thereby facilitating estimates of carbon dynamics.

Analyzing Genetic Diversity for Virulence and Resistance Phenotypes in Populations of Stem Rust (Puccinia graminis f. sp. secalis) and Winter Rye (Secale cereale).

PubMed

Miedaner, Thomas; Schmitt, Ann-Kristin; Klocke, Bettina; Schmiedchen, Brigitta; Wilde, Peer; Spieß, Hartmut; Szabo, Lilla; Koch, Silvia; Flath, Kerstin

2016-11-01

Stem rust (Puccinia graminis f. sp. secalis) leads to considerable yield losses in rye-growing areas with continental climate, from Eastern Germany to Siberia. For implementing resistance breeding, it is of utmost importance to (i) analyze the diversity of stem rust populations in terms of pathotypes (= virulence combinations) and (ii) identify resistance sources in winter rye populations. We analyzed 323 single-uredinial isolates mainly collected from German rye-growing areas across 3 years for their avirulence/virulence on 15 rye inbred differentials. Out of these, 226 pathotypes were detected and only 56 pathotypes occurred more than once. This high diversity was confirmed by a Simpson index of 1.0, a high Shannon index (5.27), and an evenness index of 0.97. In parallel, we investigated stem rust resistance among and within 121 heterogeneous rye populations originating mainly from Russia, Poland, Austria, and the United States across 3 to 15 environments (location-year combinations). While German rye populations had an average stem rust severity of 49.7%, 23 nonadapted populations were significantly (P < 0.01) more resistant with a stem rust severity ranging from 3 to 40%. Out of these, two modern Russian breeding populations and two old Austrian landraces were the best harboring 32 to 70% fully resistant plants across 8 to 10 environments. These populations with the lowest disease severity in adult-plant stage in the field also displayed resistance in leaf segment tests. In conclusion, stem rust populations are highly diverse and the majority of resistances in rye populations seems to be race specific.

Metabolic enzymes: key modulators of functionality in cancer stem-like cells

PubMed Central

Dong, Bo-Wen; Qin, Guang-Ming; Luo, Yan; Mao, Jian-Shan

2017-01-01

Cancer Stem-like Cells (CSCs) are a subpopulation of cancer cells with self-renewal capacity and are important for the initiation, progression and recurrence of cancer diseases. The metabolic profile of CSCs is consistent with their stem-like properties. Studies have indicated that enzymes, the main regulators of cellular metabolism, dictate functionalities of CSCs in both catalysis-dependent and catalysis-independent manners. This paper reviews diverse studies of metabolic enzymes, and describes the effects of these enzymes on metabolic adaptation, gene transcription and signal transduction, in CSCs. PMID:28009990

Metabolic enzymes: key modulators of functionality in cancer stem-like cells.

PubMed

Dong, Bo-Wen; Qin, Guang-Ming; Luo, Yan; Mao, Jian-Shan

2017-02-21

Cancer Stem-like Cells (CSCs) are a subpopulation of cancer cells with self-renewal capacity and are important for the initiation, progression and recurrence of cancer diseases. The metabolic profile of CSCs is consistent with their stem-like properties. Studies have indicated that enzymes, the main regulators of cellular metabolism, dictate functionalities of CSCs in both catalysis-dependent and catalysis-independent manners. This paper reviews diverse studies of metabolic enzymes, and describes the effects of these enzymes on metabolic adaptation, gene transcription and signal transduction, in CSCs.

Idiopathic aplastic anemia: diagnosis and classification.

PubMed

Dolberg, Osnat Jarchowsky; Levy, Yair

2014-01-01

Aplastic anemia (AA) is a disease characterized by pancytopenia and hypoplastic bone marrow caused by the decrease of hematopoietic stem cells. The pathogenesis of AA is complex and involves an abnormal hematopoietic microenvironment, hematopoietic stem cell/progenitor cell deficiencies and immunity disorders. Survival in severe aplastic anemia (SAA) has markedly improved in the past 4 decades because of advances in hematopoietic stem cell transplantation, immunosuppressive and biologic drugs, and supportive care. Herein, we will update the main issues concern AA according to our literature review. Copyright © 2014 Elsevier B.V. All rights reserved.

A model to forecast short-term snowmelt runoff using synoptic observations of streamflow, temperature, and precipitation

USGS Publications Warehouse

Tangborn, Wendell V.

1980-01-01

Snowmelt runoff is forecast with a statistical model that utilizes daily values of stream discharge, gaged precipitation, and maximum and minimum observations of air temperature. Synoptic observations of these variables are made at existing low- and medium-altitude weather stations, thus eliminating the difficulties and expense of new, high-altitude installations. Four model development steps are used to demonstrate the influence on prediction accuracy of basin storage, a preforecast test season, air temperature (to estimate ablation), and a prediction based on storage. Daily ablation is determined by a technique that employs both mean temperature and a radiative index. Radiation (both long- and short-wave components) is approximated by using the range in daily temperature, which is shown to be closely related to mean cloud cover. A technique based on the relationship between prediction error and prediction season weather utilizes short-term forecasts of precipitation and temperature to improve the final prediction. Verification of the model is accomplished by a split sampling technique for the 1960–1977 period. Short- term (5–15 days) predictions of runoff throughout the main snowmelt season are demonstrated for mountain drainages in western Washington, south-central Arizona, western Montana, and central California. The coefficient of prediction (Cp) based on actual, short-term predictions for 18 years is for Thunder Creek (Washington), 0.69; for South Fork Flathead River (Montana), 0.45; for the Black River (Arizona), 0.80; and for the Kings River (California), 0.80.

Strong effects of predation by fishes on an invasive macroinvertebrate in a large floodplain river

USGS Publications Warehouse

Bartsch, M.R.; Bartsch, L.A.; Gutreuter, S.

2005-01-01

We assessed the effects of fish predation on zebra mussels (Dreissena polymorpha) in Navigation Pool 8 of the Upper Mississippi River from 13 May to 5 October, 1998. Concrete-block samplers were deployed at 18 randomly chosen sites in the main-channel border, with 6 sites in the upper, middle, and lower segments of the pool. Two blocks, 1 of which was enclosed in a cage to exclude large predatory fishes, were deployed at each site. After 145 d, blocks were retrieved from 12 of the 18 sites, and zebra mussels were found on all blocks. Densities of zebra mussels were higher on caged blocks than uncaged blocks, and the magnitudes of the differences varied spatially. Mean mussel densities on uncaged blocks were reduced by 66%, 86%, and 20% compared to caged blocks in the upper, middle, and lower pool segments, respectively, over the 145-d interval. Mean daily instantaneous zebra mussel mortality rates from large predators ranged from 0.0016 to 0.0138. Similarly, biomass of zebra mussels was higher on caged than uncaged blocks. Mean mussel biomass on uncaged blocks was reduced by 64% pool-wide, relative to biomass on caged blocks. Zebra mussels were consumed by at least 6 fish taxa including redhorse stickers (Moxostoma spp.), common carp (Cyprinus carpio), bluegill (Lepomis macrochirus), quillback carpsucker (Carpiodes cyprinus), flathead catfish (Pylodictis olivaris), and freshwater drum (Aplodinotus grunniens). Fish predation had an important moderating effect on zebra mussel demography in Pool 8.

RFLP-facilitated investigation of the quantitative resistance of rice to brown planthopper ( Nilaparvata lugens).

PubMed

Xu, X. F.; Mei, H. W.; Luo, L. J.; Cheng, X. N.; Li, Z. K.

2002-02-01

Quantitative trait loci (QTLs), conferring quantitative resistance to rice brown planthopper (BPH), were investigated using 160 F(11) recombinant inbred lines (RILs) from the Lemont/Teqing cross, a complete RFLP map, and replicated phenotyping of seedbox inoculation. The paternal indica parent, Teqing, was more-resistant to BPH than the maternal japonica parent, Lemont. The RILs showed transgressive segregation for resistance to BPH. Seven main-effect QTLs and many epistatic QTL pairs were identified and mapped on the 12 rice chromosomes. Collectively, the main-effect and epistatic QTLs accounted for over 70% of the total variation in damage scores. Teqing has the resistance allele at four main-effect QTLs, and the Lemont allele resulted in resistance at the other three. Of the main-effect QTLs identified, QBphr5b was mapped to the vicinity of gl1, a major gene controlling leaf and stem pubescence. The Teqing allele controlling leaf and stem pubescence was associated with resistance, while the Lemont allele for glabrous stem and leaves was associated with susceptibility, indicating that this gene may have contributed to resistance through antixenosis. Similar to the reported BPH resistance genes, the other six detected main-effect QTLs were all mapped to regions where major disease resistance genes locate, suggesting they might have contributed either to antibiosis or tolerance. Our results indicated that marker-aided pyramiding of major resistance genes and QTLs should provide effective and stable control over this devastating pest.

Photosynthesis and yield reductions from wheat stem sawfly (Hymenoptera: Cephidae): interactions with wheat solidness, water stress, and phosphorus deficiency.

PubMed

Delaney, Kevin J; Weaver, David K; Peterson, Robert K D

2010-04-01

The impact of herbivory on plants is variable and influenced by several factors. The current study examined causes of variation in the impact of larval stem mining by the wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), on spring wheat, Triticum aestivum L. We performed greenhouse experiments over 2 yr to (1) study whether biotic (hollow versus solid stemmed host wheat) and abiotic (water, phosphorus stress) factors interact with C. cinctus stem mining to influence degree of mined stem physiological (photosynthesis) and yield (grain weight) reductions; and (2) determine whether whole plant yield compensatory responses occur to offset stem-mining reductions. Flag leaf photosynthetic reduction was not detected 16-20 d after infestation, but were detected at 40-42 d and doubled from water or phosphorus stresses. Main stem grain weight decreased from 10 to 25% from stem mining, largely due to reductions in grain size, with greater reductions under low phosphorus and/or water levels. Phosphorus-deficient plants without water stress were most susceptible to C. cinctus, more than doubling the grain weight reduction due to larval feeding relative to other water and phosphorus treatments. Two solid stemmed varieties with stem mining had less grain weight loss than a hollow stemmed variety, so greater internal mechanical resistance may reduce larval stem mining and plant yield reductions. Our results emphasize the importance of sufficient water and macronutrients for plants grown in regions impacted by C. cinctus. Also, solid stemmed varieties not only reduce wheat lodging from C. cinctus, they may reduce harvested grain losses from infested stems.

Biomechanical differences in the stem straightening process among Pinus pinaster provenances. A new approach for early selection of stem straightness.

PubMed

Sierra-de-Grado, Rosario; Pando, Valentín; Martínez-Zurimendi, Pablo; Peñalvo, Alejandro; Báscones, Esther; Moulia, Bruno

2008-06-01

Stem straightness is an important selection trait in Pinus pinaster Ait. breeding programs. Despite the stability of stem straightness rankings in provenance trials, the efficiency of breeding programs based on a quantitative index of stem straightness remains low. An alternative approach is to analyze biomechanical processes that underlie stem form. The rationale for this selection method is that genetic differences in the biomechanical processes that maintain stem straightness in young plants will continue to control stem form throughout the life of the tree. We analyzed the components contributing most to genetic differences among provenances in stem straightening processes by kinetic analysis and with a biomechanical model defining the interactions between the variables involved (Fournier's model). This framework was tested on three P. pinaster provenances differing in adult stem straightness and growth. One-year-old plants were tilted at 45 degrees, and individual stem positions and sizes were recorded weekly for 5 months. We measured the radial extension of reaction wood and the anatomical features of wood cells in serial stem cross sections. The integral effect of reaction wood on stem leaning was computed with Fournier's model. Responses driven by both primary and secondary growth were involved in the stem straightening process, but secondary-growth-driven responses accounted for most differences among provenances. Plants from the straight-stemmed provenance showed a greater capacity for stem straightening than plants from the sinuous provenances mainly because of (1) more efficient reaction wood (higher maturation strains) and (2) more pronounced secondary-growth-driven autotropic decurving. These two process-based traits are thus good candidates for early selection of stem straightness, but additional tests on a greater number of genotypes over a longer period are required.

A history of scanning electron microscopy developments: towards "wet-STEM" imaging.

PubMed

Bogner, A; Jouneau, P-H; Thollet, G; Basset, D; Gauthier, C

2007-01-01

A recently developed imaging mode called "wet-STEM" and new developments in environmental scanning electron microscopy (ESEM) allows the observation of nano-objects suspended in a liquid phase, with a few manometers resolution and a good signal to noise ratio. The idea behind this technique is simply to perform STEM-in-SEM, that is SEM in transmission mode, in an environmental SEM. The purpose of the present contribution is to highlight the main advances that contributed to development of the wet-STEM technique. Although simple in principle, the wet-STEM imaging mode would have been limited before high brightness electron sources became available, and needed some progresses and improvements in ESEM. This new technique extends the scope of SEM as a high-resolution microscope, relatively cheap and widely available imaging tool, for a wider variety of samples.

Therapeutics with SPION-labeled stem cells for the main diseases related to brain aging: a systematic review.

PubMed

Alvarim, Larissa T; Nucci, Leopoldo P; Mamani, Javier B; Marti, Luciana C; Aguiar, Marina F; Silva, Helio R; Silva, Gisele S; Nucci-da-Silva, Mariana P; DelBel, Elaine A; Gamarra, Lionel F

2014-01-01

The increase in clinical trials assessing the efficacy of cell therapy for structural and functional regeneration of the nervous system in diseases related to the aging brain is well known. However, the results are inconclusive as to the best cell type to be used or the best methodology for the homing of these stem cells. This systematic review analyzed published data on SPION (superparamagnetic iron oxide nanoparticle)-labeled stem cells as a therapy for brain diseases, such as ischemic stroke, Parkinson's disease, amyotrophic lateral sclerosis, and dementia. This review highlights the therapeutic role of stem cells in reversing the aging process and the pathophysiology of brain aging, as well as emphasizing nanotechnology as an important tool to monitor stem cell migration in affected regions of the brain.

Metformin repositioning as antitumoral agent: selective antiproliferative effects in human glioblastoma stem cells, via inhibition of CLIC1-mediated ion current

PubMed Central

Barbieri, Federica; Peretti, Marta; Pizzi, Erika; Pattarozzi, Alessandra; Carra, Elisa; Sirito, Rodolfo; Daga, Antonio; Curmi, Paul M.G.; Mazzanti, Michele; Florio, Tullio

2014-01-01

Epidemiological and preclinical studies propose that metformin, a first-line drug for type-2 diabetes, exerts direct antitumor activity. Although several clinical trials are ongoing, the molecular mechanisms of this effect are unknown. Here we show that chloride intracellular channel-1 (CLIC1) is a direct target of metformin in human glioblastoma cells. Metformin exposure induces antiproliferative effects in cancer stem cell-enriched cultures, isolated from three individual WHO grade IV human glioblastomas. These effects phenocopy metformin-mediated inhibition of a chloride current specifically dependent on CLIC1 functional activity. CLIC1 ion channel is preferentially active during the G1-S transition via transient membrane insertion. Metformin inhibition of CLIC1 activity induces G1 arrest of glioblastoma stem cells. This effect was time-dependent, and prolonged treatments caused antiproliferative effects also for low, clinically significant, metformin concentrations. Furthermore, substitution of Arg29 in the putative CLIC1 pore region impairs metformin modulation of channel activity. The lack of drugs affecting cancer stem cell viability is the main cause of therapy failure and tumor relapse. We identified CLIC1 not only as a modulator of cell cycle progression in human glioblastoma stem cells but also as the main target of metformin's antiproliferative activity, paving the way for novel and needed pharmacological approaches to glioblastoma treatment. PMID:25361004

Metformin repositioning as antitumoral agent: selective antiproliferative effects in human glioblastoma stem cells, via inhibition of CLIC1-mediated ion current.

PubMed

Gritti, Marta; Würth, Roberto; Angelini, Marina; Barbieri, Federica; Peretti, Marta; Pizzi, Erika; Pattarozzi, Alessandra; Carra, Elisa; Sirito, Rodolfo; Daga, Antonio; Curmi, Paul M G; Mazzanti, Michele; Florio, Tullio

2014-11-30

Epidemiological and preclinical studies propose that metformin, a first-line drug for type-2 diabetes, exerts direct antitumor activity. Although several clinical trials are ongoing, the molecular mechanisms of this effect are unknown. Here we show that chloride intracellular channel-1 (CLIC1) is a direct target of metformin in human glioblastoma cells. Metformin exposure induces antiproliferative effects in cancer stem cell-enriched cultures, isolated from three individual WHO grade IV human glioblastomas. These effects phenocopy metformin-mediated inhibition of a chloride current specifically dependent on CLIC1 functional activity. CLIC1 ion channel is preferentially active during the G1-S transition via transient membrane insertion. Metformin inhibition of CLIC1 activity induces G1 arrest of glioblastoma stem cells. This effect was time-dependent, and prolonged treatments caused antiproliferative effects also for low, clinically significant, metformin concentrations. Furthermore, substitution of Arg29 in the putative CLIC1 pore region impairs metformin modulation of channel activity. The lack of drugs affecting cancer stem cell viability is the main cause of therapy failure and tumor relapse. We identified CLIC1 not only as a modulator of cell cycle progression in human glioblastoma stem cells but also as the main target of metformin's antiproliferative activity, paving the way for novel and needed pharmacological approaches to glioblastoma treatment.

Building Relationships, Sharing Resources, and Opening Opportunities: A STEM Learning Community Builds Social Capital for Students with Disabilities

ERIC Educational Resources Information Center

Whitney, Jean; Langley-Turnbaugh, Samantha; Lovewell, Lynn; Moeller, Babette

2012-01-01

This article describes a learning community designed for university students with disabilities in science, technology, engineering, and math (STEM) majors at the University of Southern Maine. The Learning Community (LC) seminar is a credit-bearing class and part of a pipeline of supports and services for high school and college students with…

[Studies on extraction process of the main saponin constituents from the stem bark of Kalopanax septemlobus in Guangxi].

PubMed

Yang, Yue; Yang, Xin-ping; Liu, Xiao-fu; Jiang, Xiao-jun

2009-09-01

Using orthogonal experiment design, the total saponin constituents were obtained by refluxing extraction with alcohol and separated by macroporous adsorption resin and n-Butyl alcohol from the stem bark of Kalopanax septemlobus. According to the purity analysis and the yield, the extraction process was optimized. The results showed that the main saponin constituents were gained with a yield of 1.32% by using macroporous adsorption resin but 1.05% by using n-Butyl alcohol. The former was more efficient than the latter on both yield and color. The optimal process with isolation by macroporous adsorption resin is cheap, simple and practical.

Geomorphic characteristics and classification of Duluth-area streams, Minnesota

USGS Publications Warehouse

Fitzpatrick, Faith A.; Peppler, Marie C.; DePhilip, Michele M.; Lee, Kathy E.

2006-01-01

In 2003 and 2004, a geomorphic assessment of streams in 20 watersheds in the Duluth, Minn., area was conducted to identify and summarize geomorphic characteristics, processes, disturbance mechanisms, and potential responses to disturbance. Methods used to assess the streams included watershed characterization, descriptions of segment slopes and valley types, historical aerial photograph interpretation, and rapid field assessments and intensive field surveys of stream reaches. Geomorphic conditions were summarized into a segment-scale classification with 15 categories mainly based on drainage-network position and slope, and, secondarily, based on geologic setting, valley type, and dominant geomorphic processes. Main causes of geomorphic disturbance included historical logging and agriculture, and ongoing urban development, human-caused channel alterations, road and storm sewer drainage, ditching, hiking trails, and gravel pits or quarries. Geomorphic responses to these disturbances are dependent on a combination of drainage-network position, slope, and geologic setting. Geologic setting is related to drainage-network position because the geologic deposits parallel the Lake Superior shoreline. Headwater streams in large watersheds flow over glacial deposits above altitudes of about 1,200 feet (ft). Headwater tributaries and upper main stems have ditch-like channels with gentle slopes and no valleys. Urban development and road drainage cause increased runoff and flood peaks in these segments resulting in channel widening. Below about 1,200 ft, main-stem segments generally are affected by bedrock type and structure and have steep slopes and confined or entrenched valleys. Increases in flood peaks do not cause incision or widening in the bedrock-controlled valleys; instead, the flow and scour areas are expanded. Feeder tributaries to these main stems have steep, confined valleys and may be sources for sediment from urban areas, road runoff, or storm sewer outfalls. Main-stem segments near the glacial deposits/surficial bedrock contact (1,000–1,200 ft) have the most potential for response to disturbance because they tend to have narrow valleys with sandy glacial lakeshore deposits and moderate slopes. Increases in flood peaks (from upstream increases in runoff) increase the potential for landslides and mass wasting from valley sides as well as channel widening.

Stem phototropism of trees: a possible significant factor in determining stem inclination on forest slopes.

PubMed

Matsuzaki, Jun; Masumori, Masaya; Tange, Takeshi

2006-09-01

The main stems of trees on forest slopes incline down the slope to various extents that are characteristic of the species. The inclination has been explained as an active response to a horizontally asymmetrical light environment, but the contributing physiological mechanisms are unknown. The present study tested the hypothesis that stem phototropism, gravitropism, or a combination of the two determines the inclination of tree stems on forest slopes. Cryptomeria japonica, Pinus densiflora, Quercus myrsinaefolia and Q. serrata were studied. Measurements were made of stem inclination of mature trees on forest slopes in uniform plantations of each species, and changes in stem inclination of potted seedlings in response to illumination treatments (unilateral or overhead) and inclination treatments (artificially inclined or erect). Indices of phototropic and gravitropic responsiveness were evaluated for each species, calculated from the change in stem inclination in response to artificial inclination with unilateral or overhead illumination. Stem inclination on forest slopes varied significantly among species: Q. serrata inclined most in the down-slope direction, C. japonica inclined the least, and P. densiflora and Q. myrsinaefolia were intermediate. The change in stem inclination of seedlings in each treatment varied significantly among species. One-year-old stems of Q. serrata and 2-year-old stems of Q. myrsinaefolia bent toward the light source. Interspecific variation in the change in stem inclination in response to the unilateral illumination or that in the index of phototropic responsiveness was strongly correlated with the variation in stem inclination on forest slopes. The orientation of woody stems that have finished elongation can be actively controlled by phototropism. Interspecific variation in phototropic responsiveness of trees is a possible significant determinant of interspecific variation in stem inclination on forest slopes.

Stem Phototropism of Trees: A Possible Significant Factor in Determining Stem Inclination on Forest Slopes

PubMed Central

MATSUZAKI, JUN; MASUMORI, MASAYA; TANGE, TAKESHI

2006-01-01

• Background and Aims The main stems of trees on forest slopes incline down the slope to various extents that are characteristic of the species. The inclination has been explained as an active response to a horizontally asymmetrical light environment, but the contributing physiological mechanisms are unknown. The present study tested the hypothesis that stem phototropism, gravitropism, or a combination of the two determines the inclination of tree stems on forest slopes. • Methods Cryptomeria japonica, Pinus densiflora, Quercus myrsinaefolia and Q. serrata were studied. Measurements were made of stem inclination of mature trees on forest slopes in uniform plantations of each species, and changes in stem inclination of potted seedlings in response to illumination treatments (unilateral or overhead) and inclination treatments (artificially inclined or erect). Indices of phototropic and gravitropic responsiveness were evaluated for each species, calculated from the change in stem inclination in response to artificial inclination with unilateral or overhead illumination. • Key Results Stem inclination on forest slopes varied significantly among species: Q. serrata inclined most in the down-slope direction, C. japonica inclined the least, and P. densiflora and Q. myrsinaefolia were intermediate. The change in stem inclination of seedlings in each treatment varied significantly among species. One-year-old stems of Q. serrata and 2-year-old stems of Q. myrsinaefolia bent toward the light source. Interspecific variation in the change in stem inclination in response to the unilateral illumination or that in the index of phototropic responsiveness was strongly correlated with the variation in stem inclination on forest slopes. • Conclusions The orientation of woody stems that have finished elongation can be actively controlled by phototropism. Interspecific variation in phototropic responsiveness of trees is a possible significant determinant of interspecific variation in stem inclination on forest slopes. PMID:16790467

[Stem sap flow and water consumption of Tamarix ramosissima in hinterland of Taklimakan Desert].

PubMed

Xu, Hao; Zhang, Xi-Ming; Yan, Hai-Long; Yao, Shi-Jun

2007-04-01

From April to November 2005, the stem sap flow and water consumption of Tamarix ramosissima in the hinterland of Taklimakan Desert was measured by Flow-32 System. The results showed that, in the extremely arid hinterland of Taklimakan Desert and under enough water supply, the average daily water consumption of T. ramosissima with a stem diameter of 3.5 cm and 2.0 cm was 6.322 kg and 1.179 kg, respectively in one growth season. The stem sap flow of T. ramosissima presented a single-peaked curve, with an obvious day and night variation rhythm and fluctuated with environment factors. Under enough water supply, the environmenal factors such as total radiation, wind speed and air temperature were the main factors affecting the stem sap flow, and the dynamics of stem sap flow could be predicted by the liner regression model based on total radiation and wind speed. Because of the extremely arid environment and enough water supply, T. ramosissima had a relatively higher stem sap flow rate and a great water consumption.

[Embryonic stem cells - a scientific by-product of the assisted reproduction technology?].

PubMed

Sterthaus, Oliver; Zhang, Hong; De Geyter, Christian

2009-12-01

The differentiation potential of embryonic stem (ES) cells seems to be higher when compared to adult stem cells, which mainly differentiate into certain tissue types only. ES cells have the potential to play an important role in regenerative medicine as demonstrated with murine ES cells. However, with human embryonic stem cells (hESC) several obstacles still have to be overcome, when these are to be used in clinical applications. The expansion of hESC, safety issues as well as the immune-tolerance after transplantation are all problems that still have to be solved. Since 2005 the derivation of hESC lines from super-numerous embryos has become permitted in Switzerland, albeit under strictly restrictive guidelines. In 2008 the Basler hESC laboratory was successful in derivating the first hESC line with a normal chromosome complement in Switzerland (CHES2). Now, new applications allow the personalized establishment of immune-tolerant stem cells, which lead to the replacement of therapeutic cloning by induced pluripotent stem cells (iPS).

Co-combustion characteristics and blending optimization of tobacco stem and high-sulfur bituminous coal based on thermogravimetric and mass spectrometry analyses.

PubMed

Zhang, Kaihua; Zhang, Kai; Cao, Yan; Pan, Wei-ping

2013-03-01

Despite much research on co-combustion of tobacco stem and high-sulfur coal, their blending optimization has not been effectively found. This study investigated the combustion profiles of tobacco stem, high-sulfur bituminous coal and their blends by thermogravimetric analysis. Ignition and burnout performances, heat release performances, and gaseous pollutant emissions were also studied by thermogravimetric and mass spectrometry analyses. The results indicated that combustion of tobacco stem was more complicated than that of high-sulfur bituminous coal, mainly shown as fixed carbon in it was divided into two portions with one early burning and the other delay burning. Ignition and burnout performances, heat release performances, and gaseous pollutant emissions of the blends present variable trends with the increase of tobacco stem content. Taking into account the above three factors, a blending ratio of 0–20% tobacco stem content is conservatively proposed as optimum amount for blending. Copyright © 2012 Elsevier Ltd. All rights reserved.

The Decay of Stem Cell Nourishment at the Niche

PubMed Central

de Mora, Jaime Font

2013-01-01

Abstract One of the main features of human aging is the loss of adult stem cell homeostasis. Organs that are very dependent on adult stem cells show increased susceptibility to aging, particularly organs that present a vascular stem cell niche. Reduced regenerative capacity in tissues correlates with reduced stem cell function, which parallels a loss of microvascular density (rarefraction) and plasticity. Moreover, the age-related loss of microvascular plasticity and rarefaction has significance beyond metabolic support for tissues because stem cell niches are regulated co-ordinately with the vascular cells. In addition, microvascular rarefaction is related to increased inflammatory signals that may negatively regulate the stem cell population. Thus, the processes of microvascular rarefaction, adult stem cell dysfunction, and inflammation underlie the cycle of physiological decline that we call aging. Observations from new mouse models and humans are discussed here to support the vascular aging theory. We develop a novel theory to explain the complexity of aging in mammals and perhaps in other organisms. The connection between vascular endothelial tissue and organismal aging provides a potential evolutionary conserved mechanism that is an ideal target for the development of therapies to prevent or delay age-related processes in humans. PMID:23937078

Properties of skin stem cells and their potential clinical applications in modern dermatology.

PubMed

Niezgoda, Anna; Niezgoda, Piotr; Nowowiejska, Laura; Białecka, Agnieszka; Męcińska-Jundziłł, Kaja; Adamska, Urszula; Czajkowski, Rafał

2017-06-01

Stem cells play an important role in medical science, and scientists are investing large sums in order to perform sophisticated studies designed to establish potential clinical applications of stem cells. Growing experience has enabled researchers to determine the precise nature of stem cell division. Although the properties of this particular population of cells have been known and used for some time, mainly with regards to bone marrow-derived mesenchymal stem cell transplantation, we now face a significant challenge in implementing the practical use of skin-derived precursors, making it possible to avoid the necessity for patients to undergo invasive procedures in order to obtain stem cells from bone marrow. Multiple trials have so far been performed, bringing hope for the treatment of disorders previously considered untreatable. Patients suffering from a number of dermatological diseases, including malignant melanoma, systemic lupus erythematosus, vitiligo, alopecia or junctional epidermolysis bullosa, may benefit from treatment based on stem cells. The aim of this review is to summarize available data on stem cells and their potential applications in the treatment of dermatological disorders. The work described is based on data published up to the end of September 2016.

Stem cell regenerative potential for plastic and reconstructive surgery.

PubMed

Boháč, Martin; Csöbönyeiová, Mária; Kupcová, Ida; Zamborský, Radoslav; Fedeleš, Jozef; Koller, Ján

2016-12-01

Stem cells represent heterogeneous population of undifferentiated cells with unique characteristics of long term self renewal and plasticity. Moreover, they are capable of active migration to diseased tissues, secretion of different bioactive molecules, and they have immunosuppressive potential as well. They occur in all tissues through life and are involved in process of embryogenesis and regeneration. During last decades stem cells attracted significant attention in each field of medicine, including plastic and reconstructive surgery. The main goal of the present review article is to present and discuss the potential of stem cells and to provide information about their safe utilization in chronic wounds and fistulae healing, scar management, breast reconstruction, as well as in bone, tendon and peripheral nerve regeneration.

Flood of April 2-4, 2005, Delaware River Main Stem from Port Jervis, New York, to Cinnaminson, New Jersey

USGS Publications Warehouse

Reed, Timothy J.; Protz, Amy R.

2007-01-01

Several conditions, including saturated soils, snowmelt, and heavy rains, caused flooding on the Delaware River on April 2-4, 2005. The event occurred 50 years after the historic 1955 Delaware River flood, and only six months after a smaller but equally notable flood on September 18-19, 2004. The Delaware River flooded for a third time in 22 months in June, 2006. The peak flows and elevations of the 2005 flood were similar to those on June 28-29, 2006. The following report describes the April 2-4, 2005, Delaware River flood, and includes the associated precipitation amounts, peak flows and elevations, and flood frequencies. A comparison of historic Delaware River floods also is presented. The appendix of the report contains detailed information for 156 high-water mark elevations obtained on the main stem of the Delaware River from Port Jervis, New York, to Cinnaminson, New Jersey, for the April 2-4, 2005 flood. The April 2005 event originated with frequent precipitation from December 2004 to March 2005 which saturated the soils in the upper Delaware River Basin. The cold winter froze some of the soils and left a snowpack at higher elevations equivalent to as much as 10 inches of water in some areas. Temperatures rose above freezing, and heavy rains averaging 1 to 3 inches on March 27, 2005, melted some of the snow, causing the Delaware River to rise; however, peak elevations were still 2 to 7 feet below flood stage. Another round of rainfall averaging 2-5 inches in the basin on April 2, 2005, melted the remaining snowpack. The combination of snowmelt and runoff from the two storms produced flood conditions along the main stem of the Delaware River. Flood frequencies of flows at selected tributaries to the Delaware River did not exceed the 35-year recurrence intervals. The Delaware River main stem peak-flow recurrence intervals ranged from 40 to 80 years; flows were approximately 20 percent less than those from the peak of record in 1955. Peak elevations exceeded National Weather Service flood stages defined at continuous-record streamflow-gaging stations by 5 to 7 feet, but were on average 3 to 5 feet lower than the peak of record in August 1955. Peak elevations determined at 48 sites along the main stem of the Delaware River defined the flood profile between the gaging stations. The peak elevation in the tide-effected portion of the Delaware (downstream of Trenton, New Jersey), occurred on April 2, 2 days before the riverine peak, as a result of water pushed into the bay by a low-pressure system situated just off the coast. Every county located along the main stem of the Delaware River was declared a Federal disaster area. Property damage estimates in Pennsylvania, New York, and New Jersey exceeded $200 million.

The NSL Chromatin-Modifying Complex Subunit KANSL2 Regulates Cancer Stem-like Properties in Glioblastoma That Contribute to Tumorigenesis.

PubMed

Ferreyra Solari, Nazarena E; Belforte, Fiorella S; Canedo, Lucía; Videla-Richardson, Guillermo A; Espinosa, Joaquín M; Rossi, Mario; Serna, Eva; Riudavets, Miguel A; Martinetto, Horacio; Sevlever, Gustavo; Perez-Castro, Carolina

2016-09-15

KANSL2 is an integral subunit of the nonspecific lethal (NSL) chromatin-modifying complex that contributes to epigenetic programs in embryonic stem cells. In this study, we report a role for KANSL2 in regulation of stemness in glioblastoma (GBM), which is characterized by heterogeneous tumor stem-like cells associated with therapy resistance and disease relapse. KANSL2 expression is upregulated in cancer cells, mainly at perivascular regions of tumors. RNAi-mediated silencing of KANSL2 in GBM cells impairs their tumorigenic capacity in mouse xenograft models. In clinical specimens, we found that expression levels of KANSL2 correlate with stemness markers in GBM stem-like cell populations. Mechanistic investigations showed that KANSL2 regulates cell self-renewal, which correlates with effects on expression of the stemness transcription factor POU5F1. RNAi-mediated silencing of POU5F1 reduced KANSL2 levels, linking these two genes to stemness control in GBM cells. Together, our findings indicate that KANSL2 acts to regulate the stem cell population in GBM, defining it as a candidate GBM biomarker for clinical use. Cancer Res; 76(18); 5383-94. ©2016 AACR. ©2016 American Association for Cancer Research.

Pluripotent Stem Cells and Gene Therapy

PubMed Central

Simara, Pavel; Motl, Jason A.; Kaufman, Dan S.

2013-01-01

Human pluripotent stem cells represent an accessible cell source for novel cell-based clinical research and therapies. With the realization of induced pluripotent stem cells (iPSCs), it is possible to produce almost any desired cell type from any patient's cells. Current developments in gene modification methods have opened the possibility for creating genetically corrected human iPSCs for certain genetic diseases that could be used later in autologous transplantation. Promising preclinical studies have demonstrated correction of disease-causing mutations in a number of hematological, neuronal and muscular disorders. This review aims to summarize these recent advances with a focus on iPSC generation techniques, as well as gene modification methods. We will then further discuss some of the main obstacles remaining to be overcome before successful application of human pluripotent stem cell-based therapy arrives in the clinic and what the future of stem cell research may look like. PMID:23353080

Thyroid hormone regulation of adult intestinal stem cells: Implications on intestinal development and homeostasis.

PubMed

Sun, Guihong; Roediger, Julia; Shi, Yun-Bo

2016-12-01

Organ-specific adult stem cells are essential for organ homeostasis, tissue repair and regeneration. The formation of such stem cells often takes place during postembryonic development, a period around birth in mammals when plasma thyroid hormone concentration is high. The life-long self-renewal of the intestinal epithelium has made mammalian intestine a valuable model to study the function and regulation and adult stem cells. On the other hand, much less is known about how the adult intestinal stem cells are formed during vertebrate development. Here, we will review some recent progresses on this subject, focusing mainly on the formation of the adult intestine during Xenopus metamorphosis. We will discuss the role of thyroid hormone signaling pathway in the process and potential molecular conservations between amphibians and mammals as well as the implications in organ homeostasis and human diseases.

Could metabolic syndrome, lipodystrophy, and aging be mesenchymal stem cell exhaustion syndromes?

PubMed

Mansilla, Eduardo; Díaz Aquino, Vanina; Zambón, Daniel; Marin, Gustavo Horacio; Mártire, Karina; Roque, Gustavo; Ichim, Thomas; Riordan, Neil H; Patel, Amit; Sturla, Flavio; Larsen, Gustavo; Spretz, Rubén; Núñez, Luis; Soratti, Carlos; Ibar, Ricardo; van Leeuwen, Michiel; Tau, José María; Drago, Hugo; Maceira, Alberto

2011-01-01

One of the most important and complex diseases of modern society is metabolic syndrome. This syndrome has not been completely understood, and therefore an effective treatment is not available yet. We propose a possible stem cell mechanism involved in the development of metabolic syndrome. This way of thinking lets us consider also other significant pathologies that could have similar etiopathogenic pathways, like lipodystrophic syndromes, progeria, and aging. All these clinical situations could be the consequence of a progressive and persistent stem cell exhaustion syndrome (SCES). The main outcome of this SCES would be an irreversible loss of the effective regenerative mesenchymal stem cells (MSCs) pools. In this way, the normal repairing capacities of the organism could become inefficient. Our point of view could open the possibility for a new strategy of treatment in metabolic syndrome, lipodystrophic syndromes, progeria, and even aging: stem cell therapies.

Could Metabolic Syndrome, Lipodystrophy, and Aging Be Mesenchymal Stem Cell Exhaustion Syndromes?

PubMed Central

Mansilla, Eduardo; Díaz Aquino, Vanina; Zambón, Daniel; Marin, Gustavo Horacio; Mártire, Karina; Roque, Gustavo; Ichim, Thomas; Riordan, Neil H.; Patel, Amit; Sturla, Flavio; Larsen, Gustavo; Spretz, Rubén; Núñez, Luis; Soratti, Carlos; Ibar, Ricardo; van Leeuwen, Michiel; Tau, José María; Drago, Hugo; Maceira, Alberto

2011-01-01

One of the most important and complex diseases of modern society is metabolic syndrome. This syndrome has not been completely understood, and therefore an effective treatment is not available yet. We propose a possible stem cell mechanism involved in the development of metabolic syndrome. This way of thinking lets us consider also other significant pathologies that could have similar etiopathogenic pathways, like lipodystrophic syndromes, progeria, and aging. All these clinical situations could be the consequence of a progressive and persistent stem cell exhaustion syndrome (SCES). The main outcome of this SCES would be an irreversible loss of the effective regenerative mesenchymal stem cells (MSCs) pools. In this way, the normal repairing capacities of the organism could become inefficient. Our point of view could open the possibility for a new strategy of treatment in metabolic syndrome, lipodystrophic syndromes, progeria, and even aging: stem cell therapies. PMID:21716667

Anti-Cancer Phytometabolites Targeting Cancer Stem Cells

PubMed Central

Torquato, Heron F.V.; Goettert, Márcia I.; Justo, Giselle Z.; Paredes-Gamero, Edgar J.

2017-01-01

Medicinal plants are a plentiful source of bioactive molecules with much structural diversity. In cancer treatment, molecules obtained from plants represent an attractive alternative to other treatments because several plant-derived compounds have exhibited lower toxicity and higher selectivity against cancer cells. In this review, we focus on the possible application of bioactive molecules obtained from plants against more primitive cell populations in cancers, cancer stem cells. Cancer stem cells are present in several kinds of tumors and are responsible for recurrences and metastases. Common anti-cancer drugs exhibit lower effectiveness against cancer stem cells because of their biological features. However, recently discovered natural phytometabolites exert cytotoxic effects on this rare population of cells in cancers. Therefore, this review presents the latest research on promising compounds from plants that can act as antitumor drugs and that mainly affect stem cell populations in cancers. PMID:28367074

Fucosylation of xyloglucan: localization of the transferase in dictyosomes of pea stem cells. [Pisum sativum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Camirand, A.; Brummell, D.; MacLachlan, G.

1987-07-01

Microsomal membranes from elongating regions of etiolated Pisum sativum stems were separated by rate-zonal centrifugation on Renografin gradients. The transfer of labeled fucose and xylose from GDP-(/sup 14/C) fucose and UDP-(/sup 14/C)xylose to xyloglucan occurred mainly in dictyosome-enriched fractions. No transferase activity was detected in secretory vesicle fractions. Pulse-chase experiments using pea stem slices incubated with (/sup 3/H)fucose suggest that xyloglucan chains are fucosylated and their structure completed within the dictyosomes, before being transported to the cell wall by secretory vesicles.

Fragmentation, Cost and Environmental Effects of Plaster Stemming Method for Blasting at A Basalt Quarry

NASA Astrophysics Data System (ADS)

Cevizci, Halim

2014-10-01

In this study, the plaster stemming application for blasting at a basalt quarry is studied. Drill cuttings are generally used in open pits and quarries as the most common stemming material since these are most readily available at blast sites. However, dry drill cuttings eject very easily from blastholes without offering much resistance to blast energy. The plaster stemming method has been found to be better than the drill cuttings stemming method due to increased confinement inside the hole and better utilization of blast explosive energy in the rock. The main advantage of the new stemming method is the reduction in the cost of blasting. At a basalt quarry, blasting costs per unit volume of rock were reduced to 15% by increasing burden and spacing distances. In addition, better fragmentation was obtained by using the plaster stemming method. Blast trials showed that plaster stemming produced finer material. In the same blast tests, +30 cm size fragments were reduced to 47.3% of the total, compared to 32.6% in the conventional method of drill cuttings stemming. With this method of stemming, vibration and air shock values increased slightly due to more blast energy being available for rock breakage but generally these increased values were small and stayed under the permitted limit for blast damage criteria unless measuring distance is too close.

Concise Review: Challenges in Regenerating the Diabetic Heart: A Comprehensive Review.

PubMed

Satthenapalli, Venkata R; Lamberts, Regis R; Katare, Rajesh G

2017-09-01

Stem cell therapy is one of the promising regenerative strategies developed to improve cardiac function in patients with ischemic heart diseases (IHD). However, this approach is limited in IHD patients with diabetes due to a progressive decline in the regenerative capacity of stem cells. This decline is mainly attributed to the metabolic memory incurred by diabetes on stem cell niche and their systemic cues. Understanding the molecular pathways involved in the diabetes-induced deterioration of stem cell function will be critical for developing new cardiac regeneration therapies. In this review, we first discuss the most common molecular alterations occurring in the diabetic stem cells/progenitor cells. Next, we highlight the key signaling pathways that can be dysregulated in a diabetic environment and impair the mobilization of stem/progenitor cells, which is essential for the transplanted/endogenous stem cells to reach the site of injury. We further discuss the possible methods of preconditioning the diabetic cardiac progenitor cell (CPC) with an aim to enrich the availability of efficient stem cells to regenerate the diseased diabetic heart. Finally, we propose new modalities for enriching the diabetic CPC through genetic or tissue engineering that would aid in developing autologous therapeutic strategies, improving the proliferative, angiogenic, and cardiogenic properties of diabetic stem/progenitor cells. Stem Cells 2017;35:2009-2026. © 2017 AlphaMed Press.

Therapeutic Potential, Challenges and Future Perspective of Cancer Stem Cells in Translational Oncology: A Critical Review.

PubMed

Shukla, Gaurav; Khera, Harvinder Kour; Srivastava, Amit Kumar; Khare, Piush; Patidar, Rahul; Saxena, Rajiv

2017-01-01

Stem cell research is a rapidly developing field that offers effective treatment for a variety of malignant and non-malignant diseases. Stem cell is a regenerative medicine associated with the replacement, repair, and restoration of injured tissue. Stem cell research is a promising field having maximum therapeutic potential. Cancer stem cells (CSCs) are the cells within the tumor that posses capacity of selfrenewal and have a root cause for the failure of traditional therapies leading to re-occurrence of cancer. CSCs have been identified in blood, breast, brain, and colon cancer. Traditional therapies target only fast growing tumor mass, but not slow-dividing cancer stem cells. It has been shown that embryonic pathways such as Wnt, Hedgehog and Notch, control self-renewal capacity and involved in cancer stem cell maintenance. Targeting of these pathways may be effective in eradicating cancer stem cells and preventing chemotherapy and radiotherapy resistance. Targeting CSCs has become one of the most effective approaches to improve the cancer survival by eradicating the main root cause of cancer. The present review will address, in brief, the importance of cancer stem cells in targeting cancer as better and effective treatment along with a concluding outlook on the scope and challenges in the implication of cancer stem cells in translational oncology. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Structural response of Caribbean dry forests to hurricane winds: a case study from Guanica Forest, Puerto Rico.

Treesearch

Skip J. Van Bloem; Ariel E. Lugo; Peter G. Murphy

2006-01-01

Tropical dry forests in the Caribbean have an uniquely short, shrubby structure with a high proportion of multiple-stemmed trees compared to dry forests elsewhere in the Neotropics. Previous studies have shown that this structure can arise without the loss of main stems from cutting, grazing, or other human intervention. The Caribbean has a high frequency of hurricanes...

Grapevines petioles are more sensitive to drought induced embolism than stems: evidence from in vivo MRI and microCT observations of hydraulic vulnerability segmentation

USDA-ARS?s Scientific Manuscript database

The concept ‘‘hydraulic vulnerability segmentation’’ represents a mechanism in which expendable distal organs (e.g. leaves attached to a woody shoot) are more susceptible to water-stress induced cavitation than the main stem of the plant. In the present work we present the first in-vivo observation ...

Health Status of Sand Flathead (Platycephalus bassensis), Inhabiting an Industrialised and Urbanised Embayment, Port Phillip Bay, Victoria as Measured by Biomarkers of Exposure and Effects

PubMed Central

Baker, Jarrad K.; Long, Sara M.; Hassell, Kathryn L.; Pettigrove, Vincent J.

2016-01-01

Port Phillip Bay, Australia, is a large semi-closed bay with over four million people living in its catchment basin. The Bay receives waters from the Yarra River which drains the city of Melbourne, as well as receiving the discharges of sewage treatment plants and petrochemical and agricultural chemicals. A 1999 study demonstrated that fish inhabiting Port Phillip Bay showed signs of effects related to pollutant exposure despite pollution management practices having been implemented for over a decade. To assess the current health status of the fish inhabiting the Bay, a follow up survey was conducted in 2015. A suite of biomarkers of exposure and effects were measured to determine the health status of Port Phillip Bay sand flathead (Platycephalus bassensis), namely ethoxyresorufin-O-deethylase (EROD) activity, polycyclic aromatic hydrocarbons (PAH) biliary metabolites, carboxylesterase activity (CbE) and DNA damage (8-oxo-dG). The reduction in EROD activity in the present study suggests a decline in the presence of EROD activity-inducing chemicals within the Bay since the 1990s. Fish collected in the most industrialised/urbanised sites did not display higher PAH metabolite levels than those in less developed areas of the Bay. Ratios of PAH biliary metabolite types were used to indicate PAH contaminant origin. Ratios indicated fish collected at Corio Bay and Hobsons Bay were subjected to increased low molecular weight hydrocarbons of petrogenic origin, likely attributed to the close proximity of these sites to oil refineries, compared to PAH biliary metabolites in fish from Geelong Arm and Mordialloc. Quantification of DNA damage indicated a localised effect of exposure to pollutants, with a 10-fold higher DNA damage level in fish sampled from the industrial site of Corio Bay relative to the less developed site of Sorrento. Overall, integration of biomarkers by multivariate analysis indicated that the health of fish collected in industrialised areas was compromised, with biologically significant biomarkers of effects (LSI, CF and DNA damage) discriminating between individuals collected in industrialised areas from observations made in fish collected in less developed areas of the Bay. PMID:27711198

Health Status of Sand Flathead (Platycephalus bassensis), Inhabiting an Industrialised and Urbanised Embayment, Port Phillip Bay, Victoria as Measured by Biomarkers of Exposure and Effects.

PubMed

Baker, Jarrad K; Long, Sara M; Hassell, Kathryn L; Pettigrove, Vincent J; Gagnon, Marthe M

2016-01-01

Port Phillip Bay, Australia, is a large semi-closed bay with over four million people living in its catchment basin. The Bay receives waters from the Yarra River which drains the city of Melbourne, as well as receiving the discharges of sewage treatment plants and petrochemical and agricultural chemicals. A 1999 study demonstrated that fish inhabiting Port Phillip Bay showed signs of effects related to pollutant exposure despite pollution management practices having been implemented for over a decade. To assess the current health status of the fish inhabiting the Bay, a follow up survey was conducted in 2015. A suite of biomarkers of exposure and effects were measured to determine the health status of Port Phillip Bay sand flathead (Platycephalus bassensis), namely ethoxyresorufin-O-deethylase (EROD) activity, polycyclic aromatic hydrocarbons (PAH) biliary metabolites, carboxylesterase activity (CbE) and DNA damage (8-oxo-dG). The reduction in EROD activity in the present study suggests a decline in the presence of EROD activity-inducing chemicals within the Bay since the 1990s. Fish collected in the most industrialised/urbanised sites did not display higher PAH metabolite levels than those in less developed areas of the Bay. Ratios of PAH biliary metabolite types were used to indicate PAH contaminant origin. Ratios indicated fish collected at Corio Bay and Hobsons Bay were subjected to increased low molecular weight hydrocarbons of petrogenic origin, likely attributed to the close proximity of these sites to oil refineries, compared to PAH biliary metabolites in fish from Geelong Arm and Mordialloc. Quantification of DNA damage indicated a localised effect of exposure to pollutants, with a 10-fold higher DNA damage level in fish sampled from the industrial site of Corio Bay relative to the less developed site of Sorrento. Overall, integration of biomarkers by multivariate analysis indicated that the health of fish collected in industrialised areas was compromised, with biologically significant biomarkers of effects (LSI, CF and DNA damage) discriminating between individuals collected in industrialised areas from observations made in fish collected in less developed areas of the Bay.

Tuning stochastic matrix models with hydrologic data to predict the population dynamics of a riverine fish.

PubMed

Sakaris, Peter C; Irwin, Elise R

2010-03-01

We developed stochastic matrix models to evaluate the effects of hydrologic alteration and variable mortality on the population dynamics of a lotic fish in a regulated river system. Models were applied to a representative lotic fish species, the flathead catfish (Pylodictis olivaris), for which two populations were examined: a native population from a regulated reach of the Coosa River (Alabama, USA) and an introduced population from an unregulated section of the Ocmulgee River (Georgia, USA). Size-classified matrix models were constructed for both populations, and residuals from catch-curve regressions were used as indices of year class strength (i.e., recruitment). A multiple regression model indicated that recruitment of flathead catfish in the Coosa River was positively related to the frequency of spring pulses between 283 and 566 m3/s. For the Ocmulgee River population, multiple regression models indicated that year class strength was negatively related to mean March discharge and positively related to June low flow. When the Coosa population was modeled to experience five consecutive years of favorable hydrologic conditions during a 50-year projection period, it exhibited a substantial spike in size and increased at an overall 0.2% annual rate. When modeled to experience five years of unfavorable hydrologic conditions, the Coosa population initially exhibited a decrease in size but later stabilized and increased at a 0.4% annual rate following the decline. When the Ocmulgee River population was modeled to experience five years of favorable conditions, it exhibited a substantial spike in size and increased at an overall 0.4% annual rate. After the Ocmulgee population experienced five years of unfavorable conditions, a sharp decline in population size was predicted. However, the population quickly recovered, with population size increasing at a 0.3% annual rate following the decline. In general, stochastic population growth in the Ocmulgee River was more erratic and variable than population growth in the Coosa River. We encourage ecologists to develop similar models for other lotic species, particularly in regulated river systems. Successful management of fish populations in regulated systems requires that we are able to predict how hydrology affects recruitment and will ultimately influence the population dynamics of fishes.

Organic compounds and cadmium in the tributaries to the Elizabeth River in New Jersey, October 2008 to November 2008: Phase II of the New Jersey Toxics Reduction Workplan for New York-New Jersey Harbor

USGS Publications Warehouse

Bonin, Jennifer L.

2010-01-01

Samples of surface water and suspended sediment were collected from the two branches that make up the Elizabeth River in New Jersey - the West Branch and the Main Stem - from October to November 2008 to determine the concentrations of selected chlorinated organic and inorganic constituents. The sampling and analyses were conducted as part of Phase II of the New York-New Jersey Harbor Estuary Plan-Contaminant Assessment and Reduction Program (CARP), which is overseen by the New Jersey Department of Environmental Protection. Phase II of the New Jersey Workplan was conducted by the U.S. Geological Survey to define upstream tributary and point sources of contaminants in those rivers sampled during Phase I work, with special emphasis on the Passaic and Elizabeth Rivers. This portion of the Phase II study was conducted on the two branches of the Elizabeth River, which were previously sampled during July and August of 2003 at low-flow conditions. Samples were collected during 2008 from the West Branch and Main Stem of the Elizabeth River just upstream from their confluence at Hillside, N.J. Both tributaries were sampled once during low-flow discharge conditions and once during high-flow discharge conditions using the protocols and analytical methods that were used in the initial part of Phase II of the Workplan. Grab samples of streamwater also were collected at each site and were analyzed for cadmium, suspended sediment, and particulate organic carbon. The measured concentrations, along with available historical suspended-sediment and stream-discharge data were used to estimate average annual loads of suspended sediment and organic compounds in the two branches of the Elizabeth River. Total suspended-sediment loads for 1975 to 2000 were estimated using rating curves developed from historical U.S. Geological Survey suspended-sediment and discharge data, where available. Concentrations of suspended-sediment-bound polychlorinated biphenyls (PCBs) in the Main Stem and the West Branch of the Elizabeth River during low-flow conditions were 534 ng/g (nanograms per gram) and 1,120 ng/g, respectively, representing loads of 27 g/yr (grams per year) and 416 g/yr, respectively. These loads were estimated using contaminant concentrations during low flow, and the assumed 25-year average discharge, and 25-year average suspended-sediment concentration. Concentrations of suspended-sediment-bound PCBs in the Main Stem and the West Branch of the Elizabeth River during high-flow conditions were 3,530 ng/g and 623 ng/g, respectively, representing loads of 176 g/yr and 231 g/yr, respectively. These loads were estimated using contaminant concentrations during high-flow conditions, the assumed 25-year average discharge, and 25-year average suspended-sediment concentration. Concentrations of suspended-sediment-bound polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-difuran compounds (PCDD/PCDFs) during low-flow conditions were 2,880 pg/g (picograms per gram) and 5,910 pg/g in the Main Stem and West Branch, respectively, representing average annual loads of 0.14 g/yr and 2.2 g/yr, respectively. Concentrations of suspended-sediment-bound PCDD/PCDFs during high-flow conditions were 40,900 pg/g and 12,400 pg/g in the Main Stem and West Branch, respectively, representing average annual loads of 2.05 g/yr and 4.6 g/yr, respectively. Total toxic equivalency (TEQ) loads (sum of PCDD/PCDF and PCB TEQs) were 3.1 mg/yr (milligrams per year) (as 2, 3, 7, 8-TCDD) in the Main Stem and 28 mg/yr in the West Branch during low-flow conditions. Total TEQ loads (sum of PCDD/PCDFs and PCBs) were 27 mg/yr (as 2, 3, 7, 8-TCDD) in the Main Stem and 32 mg/yr in the West Branch during high-flow conditions. All of these load estimates, however, are directly related to the assumed annual discharge for the two branches. Long-term measurement of stream discharge and suspended-sediment concentrations would be needed to verify these loads. On the basis of the loads cal

FLUVIAL DISTURBANCE AND WETLAND VEGETATION DEVELOPMENT, UPPER MAIN STEM, WILLAMETTE RIVER, OREGON, USA

EPA Science Inventory

Hydrogeomorphic processes drive vegetation establishment, and promote development of diverse wetland and riparian types associated with lotic ecosystems. The main objective of this study was to estimate the rate and pattern of vegetation development on bars tracked since 1936, a...

Stem cells and their potential clinical applications in psychiatric disorders.

PubMed

Ratajczak, Mariusz Z; Ciechanowicz, Andrzej K; Kucharska-Mazur, Jolanta; Samochowiec, Jerzy

2018-01-03

The robustness of stem cells is one of the major factors that directly impacts life quality and life span. Evidence has accumulated that changes in the stem cell compartment affect human mental health and serve as an indicator of psychiatric problems. It is well known that stem cells continuously replace differentiated cells and tissues that are used up during life, although this replacement occurs at a different pace in the various organs. However, the participation of local neural stem cells in regeneration of the central nervous system is controversial. It is known that low numbers of stem cells circulate continuously in peripheral blood (PB) and lymph and undergo a circadian rhythm in their PB level, with the peak occurring early in the morning and the nadir at night, and recent evidence suggests that the number and pattern of circulating stem cells in PB changes in psychotic disorders. On the other hand, progress in the creation of induced pluripotent stem cells (iPSCs) from patient somatic cells provides valuable tools with which to study changes in gene expression in psychotic patients. We will discuss the various potential sources of stem cells that are currently employed in regenerative medicine and the mechanisms that explain some of their beneficial effects as well as the emerging problems with stem cell therapies. However, the main question remains: Will it be possible in the future to modulate the stem cell compartment to reverse psychiatric problems? Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of Land-Cover Change, Floods, and Stream Position on Geomorphic Processes - Implications for Restoration Activities

USGS Publications Warehouse

Fitzpatrick, F.A.; ,

2001-01-01

A geomorphic study for North Fish Creek, a northern Wisconsin tributary to Lake Superior was analyzed to determine the hydrologic and geomorphic changes caused by clear-cut logging and agricultural activity. Discharge magnitude estimated with HEC-2 for full-channel capacities indicate that modern full-channel discharges are about twice as large as pre-1946 full-channel discharges. Flood-plain deposition rates were high along the transitional main stem after European settlement. Restoration and protection activities would be most effective if focused on watershed practices to reduce runoff and on channel restoration that reduce buff and bank erosion in the upper and transitional main stems.

Neural conduction abnormality in the brain stem and prevalence of the abnormality in late preterm infants with perinatal problems.

PubMed

Jiang, Ze Dong

2013-08-01

Neurodevelopment in late preterm infants has recently attracted considerable interest. The prevalence of brain stem conduction abnormality remains unknown. We examined maximum length sequence brain stem auditory evoked response in 163 infants, born at 33-36 weeks gestation, who had various perinatal problems. Compared with 49 normal term infants without problems, the late preterm infants showed a significant increase in III-V and I-V interpeak intervals at all 91-910/s clicks, particularly at 455 and 910/s (p < 0.01-0.001). The I-III interval was slightly increased, without statistically significant difference from the controls at any click rates. These results suggest that neural conduction along the, mainly more central or rostral part of, auditory brain stem is abnormal in late preterm infants with perinatal problems. Of the 163 late preterm infant, the number (and percentage rate) of infants with abnormal I-V interval at 91, 227, 455, and 910/s clicks was, respectively, 11 (6.5%), 17 (10.2%), 37 (22.3%), and 31 (18.7%). The number (and percentage rate) of infants with abnormal III-V interval at these rates was, respectively, 10 (6.0%), 17 (10.2%), 28 (16.9), and 36 (21.2%). Apparently, the abnormal rates were much higher at 455 and 910/s clicks than at lower rates 91 and 227/s. In total, 42 (25.8%) infants showed abnormal I-V and/or III-V intervals. Conduction in, mainly in the more central part, the brain stem is abnormal in late preterm infants with perinatal problems. The abnormality is more detectable at high- than at low-rate sensory stimulation. A quarter of late preterm infants with perinatal problems have brain stem conduction abnormality.

Investigation for the differentiation process of mouse ES cells by Raman spectroscopy

NASA Astrophysics Data System (ADS)

Yamaguchi, Yoshinori; El-Hagrasy, Maha A.; Shimizu, Eiichi; Saito, Masato; Tamiya, Eiichi

2012-03-01

The arrangement of differentiated pluripotent embryonic stem cells into three-dimensional aggregates, which are known as embryonic bodies, is a main step for progressing the embryonic stem cells differentiation. In this work, embryonic stem cells that were directly produced from the hanging drop step as a three-dimensional structure with no further twodimensional differentiation were diagnosed with Raman spectroscopy as a non-invasive and label-free technique. Raman spectroscopy was employed to discriminate between mouse embryonic bodies of different degrees of maturation. EBs were prepared applying the hanging drop method. The Raman scattering measurements were obtained in vitro with a Nanophoton RAMAN-11 micro-spectrometer (Japan: URL: www.nanophoton.jp equipped with an Olympus XLUM Plan FLN 20X/NA= 1.0 objective lens. Spectral data were smoothed, baseline corrected and normalized to the a welldefined intense 1003 cm-1 band (phenylalanine) which is insensitive to changes in conformation or environment. The differentiation process of embryonic stem cells is initiated by the removal of LIF from culture medium. 1, 7 and 17-dayold embryonic stem cells were collected and investigated by Raman spectroscopy. The main differences involve bands which decreased with maturation such as: 784 cm-1 (U, T, C ring br DNA/RNA, O-P-O str); 1177 cm-1 (cytosine, guanine) and 1578 cm-1 (G, A). It was found that with the progress of differentiation the protein content was amplified. The increase of protein to nucleic acid ratio was also previously observed with the progress of the differentiation process. Raman spectroscopy has the potential to distinguish between the Raman signatures of live embryonic stem cells with different degrees of maturation.

Presence of stem/progenitor cells in the rat penis.

PubMed

Lin, Guiting; Alwaal, Amjad; Zhang, Xiaoyu; Wang, Jianwen; Wang, Lin; Li, Huixi; Wang, Guifang; Ning, Hongxiu; Lin, Ching-Shwun; Xin, Zhongcheng; Lue, Tom F

2015-01-15

Tissue resident stem cells are believed to exist in every organ, and their identification is commonly done using a combination of immunostaining for putative stem cell markers and label-retaining cell (LRC) strategy. In this study, we employed these approaches to identify potential stem cells in the penis. Newborn rats were intraperitoneally injected with thymidine analog, 5-ethynyl-2-deoxyuridine (EdU), and their penis was harvested at 7 h, 3 days, 1 week, and 4 weeks. It was processed for EdU stains and immunofluorescence staining for stem cell markers A2B5, PCNA, and c-kit. EdU-positive cells were counted for each time point and co-localized with each stem cell marker, then isolated and cultured in vitro followed by their characterization using flowcytometry and immunofluorescence. At 7 h post-EdU injection, 410 ± 105.3 penile corporal cells were labeled in each cross-section (∼28%). The number of EdU-positive cells at 3 days increased to 536 ± 115.6, while their percentage dropped to 25%. Progressively fewer EdU-positive cells were present in the sacrificed rat penis at longer time points (1 and 4 weeks). They were mainly distributed in the subtunic and perisinusoidal spaces, and defined as subtunic penile progenitor cells (STPCs) and perisinusoidal penile progenitor cells (PPCs). These cells expressed c-kit, A2B5, and PCNA. After culturing in vitro, only ∼0.324% corporal cells were EdU-labeled LRCs and expressed A2B5/PCNA. Therefore, labeling of penis cells by EdU occurred randomly, and label retaining was not associated with expression of c-kit, A2B5, or PCNA. The penile LRCs are mainly distributed within the subtunic and perisinusoidal space.

Scanning transmission electron microscopy methods for the analysis of nanoparticles.

PubMed

Ponce, Arturo; Mejía-Rosales, Sergio; José-Yacamán, Miguel

2012-01-01

Here we review the scanning transmission electron microscopy (STEM) characterization technique and STEM imaging methods. We describe applications of STEM for studying inorganic nanoparticles, and other uses of STEM in biological and health sciences and discuss how to interpret STEM results. The STEM imaging mode has certain benefits compared with the broad-beam illumination mode; the main advantage is the collection of the information about the specimen using a high angular annular dark field (HAADF) detector, in which the images registered have different levels of contrast related to the chemical composition of the sample. Another advantage of its use in the analysis of biological samples is its contrast for thick stained sections, since HAADF images of samples with thickness of 100-120 nm have notoriously better contrast than those obtained by other techniques. Combining the HAADF-STEM imaging with the new aberration correction era, the STEM technique reaches a direct way to imaging the atomistic structure and composition of nanostructures at a sub-angstrom resolution. Thus, alloying in metallic nanoparticles is directly resolved at atomic scale by the HAADF-STEM imaging, and the comparison of the STEM images with results from simulations gives a very powerful way of analysis of structure and composition. The use of X-ray energy dispersive spectroscopy attached to the electron microscope for STEM mode is also described. In issues where characterization at the atomic scale of the interaction between metallic nanoparticles and biological systems is needed, all the associated techniques to STEM become powerful tools for the best understanding on how to use these particles in biomedical applications.

Antioxidant tannins from stem bark and fine root of Casuarina equisetifolia.

PubMed

Zhang, Shang-Ju; Lin, Yi-Ming; Zhou, Hai-Chao; Wei, Shu-Dong; Lin, Guang-Hui; Ye, Gong-Fu

2010-08-16

Structures of condensed tannins from the stem bark and fine root of Casuarina equisetifolia were identified using MALDI-TOF MS and HPLC analyses. The condensed tannins from stem bark and fine root consist predominantly of procyanidin combined with prodelphinidin and propelargonidin, and epicatechin is the main extension unit. The condensed tannins had different polymer chain lengths, varying from trimers to tridecamer for stem bark and to pentadecamer for fine root. The antioxidant activities were measured by two models: 1,1-diphenyl-2- picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing/ antioxidant power (FRAP). The condensed tannins extracted from C. equisetifolia showed very good DPPH radical scavenging activity and ferric reducing/ antioxidant power, suggesting that these extracts may be considered as new sources of natural antioxidants for food and nutraceutical products.

[CRISPR/Cas system for genome editing in pluripotent stem cells].

PubMed

Vasil'eva, E A; Melino, D; Barlev, N A

2015-01-01

Genome editing systems based on site-specific nucleases became very popular for genome editing in modern bioengineering. Human pluripotent stem cells provide a unique platform for genes function study, disease modeling, and drugs testing. Consequently, technology for fast, accurate and well controlled genome manipulation is required. CRISPR/Cas (clustered regularly interspaced short palindromic repeat/CRISPR-associated) system could be employed for these purposes. This system is based on site-specific programmable nuclease Cas9. Numerous advantages of the CRISPR/Cas system and its successful application to human stem cells provide wide opportunities for genome therapy and regeneration medicine. In this publication, we describe and compare the main genome editing systems based on site-specific programmable nucleases and discuss opportunities and perspectives of the CRISPR/Cas system for application to pluripotent stem cells.

How do STEM-interested students pursue multiple interests in their higher educational choice?

NASA Astrophysics Data System (ADS)

Vulperhorst, Jonne Pieter; Wessels, Koen Rens; Bakker, Arthur; Akkerman, Sanne Floor

2018-05-01

Interest in science, technology, engineering and mathematics (STEM) has lately received attention in research due to a gap between the number of STEM students and the needs of the labour market. As interest seems to be one of the most important factors in deciding what to study, we focus in the present study on how STEM-interested students weigh multiple interests in making educational choices. A questionnaire with both open-ended and closed-ended items was administered to 91 STEM-interested students enrolled in a STEM programme of a Dutch University for secondary school students. Results indicate that students find it important that a study programme allows them to pursue multiple interests. Some students pursued multiple interests by choosing to enrol in two programmes at the same time. Most students chose one programme that enabled them to combine multiple interests. Combinations of pursued interests were dependent on the disciplinary range of interests of students. Students who were interested in diverse domains combined interests in an educational programme across academic and non-academic domains, whilst students who were mainly interested in STEM combined only STEM-focused interests. Together these findings stress the importance of taking a multiple interest perspective on interest development and educational choice.

Present state and future perspectives of using pluripotent stem cells in toxicology research

PubMed Central

Löser, Peter

2011-01-01

The use of novel drugs and chemicals requires reliable data on their potential toxic effects on humans. Current test systems are mainly based on animals or in vitro–cultured animal-derived cells and do not or not sufficiently mirror the situation in humans. Therefore, in vitro models based on human pluripotent stem cells (hPSCs) have become an attractive alternative. The article summarizes the characteristics of pluripotent stem cells, including embryonic carcinoma and embryonic germ cells, and discusses the potential of pluripotent stem cells for safety pharmacology and toxicology. Special attention is directed to the potential application of embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) for the assessment of developmental toxicology as well as cardio- and hepatotoxicology. With respect to embryotoxicology, recent achievements of the embryonic stem cell test (EST) are described and current limitations as well as prospects of embryotoxicity studies using pluripotent stem cells are discussed. Furthermore, recent efforts to establish hPSC-based cell models for testing cardio- and hepatotoxicity are presented. In this context, methods for differentiation and selection of cardiac and hepatic cells from hPSCs are summarized, requirements and implications with respect to the use of these cells in safety pharmacology and toxicology are presented, and future challenges and perspectives of using hPSCs are discussed. PMID:21225242

Haemopoietic stem cells.

PubMed

Bellantuono, Ilaria

2004-04-01

Considerable effort has been made in recent years in understanding the mechanisms that govern stem cell generation, proliferation, self-renewal, commitment and lately plasticity. In the development of the haemopoietic system during embryonic and fetal life the notion of different pools of stem cells arising from the endothelium is gaining consensus. Gene expression profiling of populations of stem cells is bringing to light categories of genes important for self-renewal or commitment. Besides the role of transcription factors in lineage decision, the role of soluble factors and transmembrane proteins, very active at the time of embryo development, are taking central stage in the maintenance and in vitro expansion of haemopoietic stem cells (HSCs). The hierarchical model of haemopoietic development is being questioned with reports of lineage switching and plasticity of haemopoietic stem cells to non-haemopoietic cells. Yet the understanding of the overall process is still very fragmented and hypothetical. This is mainly due to the absence of appropriate markers to enable selection of homogeneous stem cell populations and the need to rely on retrospective functional assays, able only to determine the overall behaviour of a population of cells. This review is intended to be an overview of the haemopoietic system and a critical re-visitation of issues such as plasticity and self-renewal important for therapeutic applications of haemopoietic stem cells.

Paracrine effects and heterogeneity of marrow-derived stem/progenitor cells: relevance for the treatment of respiratory diseases.

PubMed

Conese, Massimo; Carbone, Annalucia; Castellani, Stefano; Di Gioia, Sante

2013-01-01

Stem cell-based treatment may represent a hope for the treatment of acute lung injury and pulmonary fibrosis, and other chronic lung diseases, such as cystic fibrosis, asthma and chronic obstructive pulmonary disease (COPD). It is well established in preclinical models that bone marrow-derived stem and progenitor cells exert beneficial effects on inflammation, immune responses and repairing of damage in virtually all lung-borne diseases. While it was initially thought that the positive outcome was due to a direct engraftment of these cells into the lung as endothelial and epithelial cells, paracrine factors are now considered the main mechanism through which stem and progenitor cells exert their therapeutic effect. This knowledge has led to the clinical use of marrow cells in pulmonary hypertension with endothelial progenitor cells (EPCs) and in COPD with mesenchymal stromal (stem) cells (MSCs). Bone marrow-derived stem cells, including hematopoietic stem/progenitor cells, MSCs, EPCs and fibrocytes, encompass a wide array of cell subsets with different capacities of engraftment and injured tissue-regenerating potential. The characterization/isolation of the stem cell subpopulations represents a major challenge to improve the efficacy of transplantation protocols used in regenerative medicine and applied to lung disorders. Copyright © 2013 S. Karger AG, Basel.

Attitudes, Interests, and Perceived Self-Efficacy toward Science of Middle School Minority Female Students: Considerations for Their Low Achievement and Participation in STEM Disciplines

ERIC Educational Resources Information Center

Dowey, Ana Lucrecia

2013-01-01

The under participation of minority females in STEM fields has been a chronic problem in the United States, mainly when it is analyzed through the lens of their relative representation in the population. The results of the first or quantitative phase, of this two phase sequential, mixed method study, revealed academic achievement or performance in…

Effects of planting density on the Biomass partitioning of intensively managed loblolly pine stands on the Piedmont and upper Coastal plain of Georgia

Treesearch

Rodney E. Will; Nikhil Narahari; Robert O. Teskey; Barry D. Shiver; Matthew Wosotowsky

2006-01-01

Increased planting density enhances overall stand growth by increasing resource capture and use. However, planting density also may affect the proportion of biomass partitioned to stem growth, a main factor controlling stand growth and yield. During the fourth growing season, we determined the biomass partitioned to leaf, branch, stem, and fine root (> 0.5mm) of...

Shen-Jing as a Chinese medicine concept might be a counterpart of stem cells in regenerative medicine.

PubMed

Ren, Yan-Bo; Huang, Jian-Hua; Cai, Wai-Jiao; Shen, Zi-Yin

2015-07-04

As the epitome of the modern regenerative medicine, stem cells were proposed in the basic sense no more than 200 years ago. However, the concept of "stem cells" existed long before the modern medical description. The hypothesis that all things, including our sentient body, were generated from a small origin was shared between Western and Chinese people. The ancient Chinese philosophers considered Jing (also known as essence) as the origin of life. In Chinese medicine (CM), Jing is mainly stored in Kidney (Shen) and the so-called Shen-Jing (Kidney essence). Here, we propose that Shen-Jing is the CM term used to express the meaning of "origin and regeneration". This theoretical discovery has at least two applications. First, the actions underlying causing Shen-Jing deficiency, such as excess sexual intercourse, chronic diseases, and aging, might damage the function of stem cells. Second, a large number of Chinese herbs with Shen-Jing-nourishing efficacy had been proven to affect stem cell proliferation and differentiation. Therefore, if Shen-Jing in CM is equivalent with stem cells in regenerative medicine, higher effective modulators for regulating stem-cell behaviors from Kidney-tonifying herbs would be expected.

Regenerative Medicine for the Heart: Perspectives on Stem-Cell Therapy

PubMed Central

Cho, Gun-Sik; Fernandez, Laviel

2014-01-01

Abstract Significance: Despite decades of progress in cardiovascular biology and medicine, heart disease remains the leading cause of death, and there is no cure for the failing heart. Since heart failure is mostly caused by loss or dysfunction of cardiomyocytes (CMs), replacing dead or damaged CMs with new CMs might be an ideal way to reverse the disease. However, the adult heart is composed mainly of terminally differentiated CMs that have no significant self-regeneration capacity. Recent Advances: Stem cells have tremendous regenerative potential and, thus, current cardiac regenerative research has focused on developing stem cell sources to repair damaged myocardium. Critical Issues: In this review, we examine the potential sources of cells that could be used for heart therapies, including embryonic stem cells and induced pluripotent stem cells, as well as alternative methods for activating the endogenous regenerative mechanisms of the heart via transdifferentiation and cell reprogramming. We also discuss the current state of knowledge of cell purification, delivery, and retention. Future Directions: Efforts are underway to improve the current stem cell strategies and methodologies, which will accelerate the development of innovative stem-cell therapies for heart regeneration. Antioxid. Redox Signal. 21, 2018–2031. PMID:25133793

[Effects of precipitation and interspecific competition on Quercus mongolica and pinus koraiensis seedlings growth].

PubMed

Wu, Jing-Lian; Wang, Miao; Lin, Fei; Hao, Zhan-Qing; Ji, Lan-Zhu; Liu, Ya-Qin

2009-02-01

Aiming at the variation of precipitation pattern caused by global warming, a field simulation experiment was conducted to study the effects of 30% increase (+W) and decrease (-W) of precipitation on the morphology, growth, and biomass partitioning of mono- and mixed cultured seedlings of Quercus mongolica and Pinus koraiensis, the two dominant tree species in temperate broad-leaved Korean pine mixed forest in Changbai Mountains. Comparing with monoculture, mixed culture increased the canopy width and main root length of Q. mongolica seedlings, but decreased the basal diameter, plant height, leaf number, and dry masses of root, stem, leaf and whole plant of P. koraiensis seedlings significantly. Treatment (-W) increased the stem/mass ratio while decreased the main root length of Q. mongolica seedlings, and decreased the main root length, leaf number, dry masses of leaf and whole plant, and leaf/mass ratio, while increased the stem/mass ratio of P. koraiensis seedlings significantly, compared with treatment CK. Treatment (+W) had no significant effect on these indices of the two species. At early growth stage, interspecific competition and precipitation pattern had significant effects on the morphology and growth of the seedlings, and the responses were much stronger for P. koraiensis than for Q. mongolica.

Scientists' perspectives on the ethical issues of stem cell research.

PubMed

Longstaff, Holly; Schuppli, Catherine A; Preto, Nina; Lafrenière, Darquise; McDonald, Michael

2009-06-01

This paper describes findings from an ethics education project funded by the Canadian Stem Cell Network (SCN). The project is part of a larger research initiative entitled "The Stem Cell Research Environment: Drawing the Evidence and Experience Together". The ethics education study began with a series of focus groups with SCN researchers and trainees as part of a "needs assessment" effort. The purpose of these discussions was to identify the main ethical issues associated with stem cell (SC) research from the perspective of the stem cell community. This paper will focus on five prominent themes that emerged from the focus group data including: (1) the source of stem cells; (2) the power of stem cells; (3) working within a charged research environment; (4) the regulatory context; and (5) ethics training for scientists. Additional discussions are planned with others involved in Canadian stem cell research (e.g., research ethics board members, policy makers) to supplement initial findings. These assessment results combined with existing bioethics literature will ultimately inform a web-based ethics education module for the SCN. We believe that our efforts are important for those analyzing the ethical, legal, and social issues (ELSI) in this area because our in depth understanding of stem cell researcher perspectives will enable us to develop more relevant and effective education material, which in turn should help SC researchers address the important ethical challenges in their area.

An overview on ethical considerations in stem cell research in Iran and ethical recommendations: A review.

PubMed

Farajkhoda, Tahmineh

2017-02-01

Conducting research on the stem cell lines might bring some worthy good to public. Human Stem Cells (hSCs) research has provided opportunities for scientific progresses and new therapies, but some complex ethical matters should be noticed to ensure that stem cell research is carried out in an ethically appropriate manner. The aim of this review article is to discuss the importance of stem cell research, code of ethics for stem cell research in Iran and ethical recommendation. Generation of stem cells for research from human embryo or adult stem cells, saving, maintenance and using of them are the main ethical, legal and jurisprudence concerns in Iran. Concerns regarding human reproduction or human cloning, breach of human dignity, genetic manipulation and probability of tumorogenisity are observed in adult/somatic stem cells. Destruction of embryo to generate stem cell is an important matter in Iran. In this regards, obtaining stem cell from donated frozen embryos through infertility treatment that would be discarded is an acceptable solution in Iran for generation of embryo for research. Ethical, legal, and jurisprudence strategies for using adult/somatic stem cells are determination of ownership of stem cells, trade prohibition of human body, supervision on bio banks and information of Oversight Committee on Stem Cell Research. Recommendations to handle ethical issues for conducting stem cell research are well-designed studies, compliance codes of ethics in biomedical research (specifically codes of ethics on stem cell research, codes of ethics on clinical trials studies and codes of ethics on animals studies), appropriate collaboration with ethics committees and respecting of rights of participants (including both of human and animal rights) in research. In addition, there is a necessity for extending global networks of bioethics for strengthening communications within organizations at both the regional and international level, strengthening legislation systems, designing and establishing convenient collaborative educational courses at different levels.

Extinction models for cancer stem cell therapy

PubMed Central

Sehl, Mary; Zhou, Hua; Sinsheimer, Janet S.; Lange, Kenneth L.

2012-01-01

Cells with stem cell-like properties are now viewed as initiating and sustaining many cancers. This suggests that cancer can be cured by driving these cancer stem cells to extinction. The problem with this strategy is that ordinary stem cells are apt to be killed in the process. This paper sets bounds on the killing differential (difference between death rates of cancer stem cells and normal stem cells) that must exist for the survival of an adequate number of normal stem cells. Our main tools are birth–death Markov chains in continuous time. In this framework, we investigate the extinction times of cancer stem cells and normal stem cells. Application of extreme value theory from mathematical statistics yields an accurate asymptotic distribution and corresponding moments for both extinction times. We compare these distributions for the two cell populations as a function of the killing rates. Perhaps a more telling comparison involves the number of normal stem cells NH at the extinction time of the cancer stem cells. Conditioning on the asymptotic time to extinction of the cancer stem cells allows us to calculate the asymptotic mean and variance of NH. The full distribution of NH can be retrieved by the finite Fourier transform and, in some parameter regimes, by an eigenfunction expansion. Finally, we discuss the impact of quiescence (the resting state) on stem cell dynamics. Quiescence can act as a sanctuary for cancer stem cells and imperils the proposed therapy. We approach the complication of quiescence via multitype branching process models and stochastic simulation. Improvements to the τ-leaping method of stochastic simulation make it a versatile tool in this context. We conclude that the proposed therapy must target quiescent cancer stem cells as well as actively dividing cancer stem cells. The current cancer models demonstrate the virtue of attacking the same quantitative questions from a variety of modeling, mathematical, and computational perspectives. PMID:22001354

Extinction models for cancer stem cell therapy.

PubMed

Sehl, Mary; Zhou, Hua; Sinsheimer, Janet S; Lange, Kenneth L

2011-12-01

Cells with stem cell-like properties are now viewed as initiating and sustaining many cancers. This suggests that cancer can be cured by driving these cancer stem cells to extinction. The problem with this strategy is that ordinary stem cells are apt to be killed in the process. This paper sets bounds on the killing differential (difference between death rates of cancer stem cells and normal stem cells) that must exist for the survival of an adequate number of normal stem cells. Our main tools are birth-death Markov chains in continuous time. In this framework, we investigate the extinction times of cancer stem cells and normal stem cells. Application of extreme value theory from mathematical statistics yields an accurate asymptotic distribution and corresponding moments for both extinction times. We compare these distributions for the two cell populations as a function of the killing rates. Perhaps a more telling comparison involves the number of normal stem cells NH at the extinction time of the cancer stem cells. Conditioning on the asymptotic time to extinction of the cancer stem cells allows us to calculate the asymptotic mean and variance of NH. The full distribution of NH can be retrieved by the finite Fourier transform and, in some parameter regimes, by an eigenfunction expansion. Finally, we discuss the impact of quiescence (the resting state) on stem cell dynamics. Quiescence can act as a sanctuary for cancer stem cells and imperils the proposed therapy. We approach the complication of quiescence via multitype branching process models and stochastic simulation. Improvements to the τ-leaping method of stochastic simulation make it a versatile tool in this context. We conclude that the proposed therapy must target quiescent cancer stem cells as well as actively dividing cancer stem cells. The current cancer models demonstrate the virtue of attacking the same quantitative questions from a variety of modeling, mathematical, and computational perspectives. Copyright © 2011 Elsevier Inc. All rights reserved.

An overview on ethical considerations in stem cell research in Iran and ethical recommendations: A review

PubMed Central

Farajkhoda, Tahmineh

2017-01-01

Conducting research on the stem cell lines might bring some worthy good to public. Human Stem Cells (hSCs) research has provided opportunities for scientific progresses and new therapies, but some complex ethical matters should be noticed to ensure that stem cell research is carried out in an ethically appropriate manner. The aim of this review article is to discuss the importance of stem cell research, code of ethics for stem cell research in Iran and ethical recommendation. Generation of stem cells for research from human embryo or adult stem cells, saving, maintenance and using of them are the main ethical, legal and jurisprudence concerns in Iran. Concerns regarding human reproduction or human cloning, breach of human dignity, genetic manipulation and probability of tumorogenisity are observed in adult/somatic stem cells. Destruction of embryo to generate stem cell is an important matter in Iran. In this regards, obtaining stem cell from donated frozen embryos through infertility treatment that would be discarded is an acceptable solution in Iran for generation of embryo for research. Ethical, legal, and jurisprudence strategies for using adult/somatic stem cells are determination of ownership of stem cells, trade prohibition of human body, supervision on bio banks and information of Oversight Committee on Stem Cell Research. Recommendations to handle ethical issues for conducting stem cell research are well-designed studies, compliance codes of ethics in biomedical research (specifically codes of ethics on stem cell research, codes of ethics on clinical trials studies and codes of ethics on animals studies), appropriate collaboration with ethics committees and respecting of rights of participants (including both of human and animal rights) in research. In addition, there is a necessity for extending global networks of bioethics for strengthening communications within organizations at both the regional and international level, strengthening legislation systems, designing and establishing convenient collaborative educational courses at different levels. PMID:28462397

Fish stocking in protected areas: Summary of a workshop

USGS Publications Warehouse

Corn, Paul Stephen; Knapp, Roland A.

2000-01-01

Native and nonnative sport fish have been introduced into the majority of historically fishless lakes in wilderness, generating conflicts between managing wilderness as natural ecosystems and providing opportunities for recreation. Managers faced with controversial and difficult decisions about how to manage wilderness lakes may not always have ready access to research relevant to these decisions. To address this problem, and to expose scientists to the concerns and constraints of managers and wilderness users, a workshop was held in October 1998 at the Flathead Lake Biological Station in Polson, Montana. Participants included 43 scientists, state and federal managers, wilderness users and advocates and students. Four subject areas were addressed: federal, state, tribal and user perspectives, community and ecosystem effects, species effects and management recommendations. Papers from the workshop are being developed for an issue of the journal Ecosystems.

Behaviors of southwestern native fishes in response to introduced catfish predators

USGS Publications Warehouse

Ward, David L.; Figiel, Chester R.

2013-01-01

Native fishes reared in hatcheries typically suffer high predation mortality when stocked into natural environments. We evaluated the behavior of juvenile bonytail Gila elegans, roundtail chub Gila robusta, razorback sucker Xyrauchen texanus, and Sonora sucker Catostomus insignis in response to introduced channel catfish Ictalurus punctatus and flathead catfish Pylodictis olivaris. Our laboratory tests indicate these species did not inherently recognize catfish as a threat, but they can quickly (within 12 h) change their behavior in response to a novel predator paired with the sight and scent of a dead conspecific. Chubs appear to avoid predation by swimming away from the threat, whereas suckers reduced movement. Effects of antipredator conditioning on survival of fish reared in hatcheries is unknown; however, our results suggest some native fish can be conditioned to recognize introduced predators, which could increase poststocking survival.

Ovarian Stem Cell Nests in Reproduction and Ovarian Aging.

PubMed

Ye, Haifeng; Zheng, Tuochen; Li, Wei; Li, Xiaoyan; Fu, Xinxin; Huang, Yaoqi; Hu, Chuan; Li, Jia; Huang, Jian; Liu, Zhengyv; Zheng, Liping; Zheng, Yuehui

2017-01-01

The fixed primordial follicles pool theory, which monopolized reproductive medicine for more than one hundred years, has been broken by the discovery, successful isolation and establishment of ovarian stem cells. It has brought more hope than ever of increasing the size of primordial follicle pool, improving ovarian function and delaying ovarian consenescence. Traditional view holds that stem cell aging contributes to the senility of body and organs. However, in the process of ovarian aging, the main factor leading to the decline of the reproductive function is the aging and degradation of ovarian stem cell nests, rather than the senescence of ovarian germ cells themselves. Recent studies have found that the immune system and circulatory system are involved in the formation of ovarian germline stem cell niches, as well as regulating the proliferation and differentiation of ovarian germline stem cells through cellular and hormonal signals. Therefore, we can improve ovarian function and delay ovarian aging by improving the immune system and circulatory system, which will provide an updated program for the treatment of premature ovarian failure (POF) and infertility. © 2017 The Author(s). Published by S. Karger AG, Basel.

Therapeutic Effects of Human Amniotic Fluid-Derived Stem Cells on Renal Interstitial Fibrosis in a Murine Model of Unilateral Ureteral Obstruction

PubMed Central

Yin, Zhongcheng; Zhou, Xudong; Li, Xiaoju; Xiao, Aiguo

2013-01-01

Interstitial fibrosis is regarded as the main pathway for the progression of chronic kidney disease (CKD) and is often associated with severe renal dysfunction. Stem cell-based therapies may provide alternative approaches for the treatment of CKD. Human amniotic fluid-derived stem cells (hAFSCs) are a novel stem cell population, which exhibit both embryonic and mesenchymal stem cell characteristics. Herein, the present study investigated whether the transplantation of hAFSCs into renal tissues could improve renal interstitial fibrosis in a murine model of unilateral ureteral obstruction (UUO). We showed that hAFSCs provided a protective effect and alleviated interstitial fibrosis as reflected by an increase in microvascular density; additionally, hAFSCs treatment beneficially modulated protein levels of vascular endothelial growth factor (VEGF), hypoxia inducible factor-1α (HIF-1α) and transforming growth factor-β1 (TGF-β1). Therefore, we hypothesize that hAFSCs could represent an alternative, readily available source of stem cells that can be applied for the treatment of renal interstitial fibrosis. PMID:23724119

The stem cell debate continues: the buying and selling of eggs for research.

PubMed

Baylis, F; McLeod, C

2007-12-01

Now that stem cell scientists are clamouring for human eggs for cloning-based stem cell research, there is vigorous debate about the ethics of paying women for their eggs. Generally speaking, some claim that women should be paid a fair wage for their reproductive labour or tissues, while others argue against the further commodification of reproductive labour or tissues and worry about voluntariness among potential egg providers. Siding mainly with those who believe that women should be financially compensated for providing eggs for research, the new stem cell guidelines of the International Society for Stem Cell Research (ISSCR) legitimise both reimbursement of direct expenses and financial compensation for many women who supply eggs for research. In this paper, the authors do not attempt to resolve the thorny issue of whether payment for eggs used in human embryonic stem cell research is ethically legitimate. Rather, they want to show specifically that the ISSCR recommended payment practices are deeply flawed and, more generally, that all payment schemes that aim to avoid undue inducement of women risk the global exploitation of economically disadvantaged women.

Lung bioengineering: physical stimuli and stem/progenitor cell biology interplay towards biofabricating a functional organ.

PubMed

Nonaka, Paula N; Uriarte, Juan J; Campillo, Noelia; Oliveira, Vinicius R; Navajas, Daniel; Farré, Ramon

2016-11-28

A current approach to obtain bioengineered lungs as a future alternative for transplantation is based on seeding stem cells on decellularized lung scaffolds. A fundamental question to be solved in this approach is how to drive stem cell differentiation onto the different lung cell phenotypes. Whereas the use of soluble factors as agents to modulate the fate of stem cells was established from an early stage of the research with this type of cells, it took longer to recognize that the physical microenvironment locally sensed by stem cells (e.g. substrate stiffness, 3D architecture, cyclic stretch, shear stress, air-liquid interface, oxygenation gradient) also contributes to their differentiation. The potential role played by physical stimuli would be particularly relevant in lung bioengineering since cells within the organ are physiologically subjected to two main stimuli required to facilitate efficient gas exchange: air ventilation and blood perfusion across the organ. The present review focuses on describing how the cell mechanical microenvironment can modulate stem cell differentiation and how these stimuli could be incorporated into lung bioreactors for optimizing organ bioengineering.

Potential of human dental stem cells in repairing the complete transection of rat spinal cord

NASA Astrophysics Data System (ADS)

Yang, Chao; Li, Xinghan; Sun, Liang; Guo, Weihua; Tian, Weidong

2017-04-01

Objective. The adult spinal cord of mammals contains a certain amount of neural precursor cells, but these endogenous cells have a limited capacity for replacement of lost cells after spinal cord injury. The exogenous stem cells transplantation has become a therapeutic strategy for spinal cord repairing because of their immunomodulatory and differentiation capacity. In addition, dental stem cells originating from the cranial neural crest might be candidate cell sources for neural engineering. Approach. Human dental follicle stem cells (DFSCs), stem cells from apical papilla (SCAPs) and dental pulp stem cells (DPSCs) were isolated and identified in vitro, then green GFP-labeled stem cells with pellets were transplanted into completely transected spinal cord. The functional recovery of rats and multiple neuro-regenerative mechanisms were explored. Main results. The dental stem cells, especially DFSCs, demonstrated the potential in repairing the completely transected spinal cord and promote functional recovery after injury. The major involved mechanisms were speculated below: First, dental stem cells inhibited the expression of interleukin-1β to reduce the inflammatory response; second, they inhibited the expression of ras homolog gene family member A (RhoA) to promote neurite regeneration; third, they inhibited the sulfonylurea receptor1 (SUR-1) expression to reduce progressive hemorrhagic necrosis; lastly, parts of the transplanted cells survived and differentiated into mature neurons and oligodendrocytes but not astrocyte, which is beneficial for promoting axons growth. Significance. Dental stem cells presented remarkable tissue regenerative capability after spinal cord injury through immunomodulatory, differentiation and protection capacity.

NF-κB Participates in the Stem Cell Phenotype of Ovarian Cancer Cells.

PubMed

Gonzalez-Torres, Carolina; Gaytan-Cervantes, Javier; Vazquez-Santillan, Karla; Mandujano-Tinoco, Edna Ayerim; Ceballos-Cancino, Gisela; Garcia-Venzor, Alfredo; Zampedri, Cecilia; Sanchez-Maldonado, Paulina; Mojica-Espinosa, Raul; Jimenez-Hernandez, Luis Enrique; Maldonado, Vilma

2017-05-01

NF-κB is a transcription factor involved in cancer stem cells maintenance of many tumors. Little is known about the specific stem-associated upstream regulators of this pathway in ovarian cancer. The Aim of the study was to analyze the role of the canonical and non-canonical NF-κB pathways in stem cells of ovarian cancer cell lines. Stem cells were isolated using sorting cytometry. Western blot and RT-PCR were used to quantify protein and messenger RNA levels. Loss and gain of function assays were performed using siRNAs and dominant-negative proteins, respectively. NF-κB binding activity was measured with a reporter gene assay. The stem phenotype was estimated with clonogenic assays using soft agar, colony formation, ovospheres formation and in vivo tumorigenicity assays. The CD44+ subpopulation of SKOV3 ovarian cancer cell line presented higher mRNA levels of key stemness genes, an increased tumorigenic capacity and higher expression of the RelA, RelB and IKKα. When the canonical pathway was inhibited by means of a dominant-negative version of IkBα, the stem cell population was reduced, as shown by a reduced CD44+ subpopulation, a decrease in the expression of the stemness genes and a reduction of the stem phenotype. In addition, IKKα, the main upstream non-canonical kinase, was highly expressed in the CSC population. Accordingly, when IKKα was inhibited using shRNAs, the expression of the stemness genes was reduced. This report is the first to show the importance of several elements of both NF-κB pathway in maintaining the ovarian cancer stem cell population. Copyright © 2017 IMSS. Published by Elsevier Inc. All rights reserved.

Paraneoplastic brain stem encephalitis.

PubMed

Blaes, Franz

2013-04-01

Paraneoplastic brain stem encephalitis can occur as an isolated clinical syndrome or, more often, may be part of a more widespread encephalitis. Different antineuronal autoantibodies, such as anti-Hu, anti-Ri, and anti-Ma2 can be associated with the syndrome, and the most frequent tumors are lung and testicular cancer. Anti-Hu-associated brain stem encephalitis does not normally respond to immunotherapy; the syndrome may stabilize under tumor treatment. Brain stem encephalitis with anti-Ma2 often improves after immunotherapy and/or tumor therapy, whereas only a minority of anti-Ri positive patients respond to immunosuppressants or tumor treatment. The Opsoclonus-myoclonus syndrome (OMS) in children, almost exclusively associated with neuroblastoma, shows a good response to steroids, ACTH, and rituximab, some patients do respond to intravenous immunoglobulins or cyclophosphamide. In adults, OMS is mainly associated with small cell lung cancer or gynecological tumors and only a small part of the patients show improvement after immunotherapy. Earlier diagnosis and treatment seem to be one major problem to improve the prognosis of both, paraneoplastic brain stem encephalitis, and OMS.

[PML-RARα and p21 are key factors for maintaining acute promyelocytic leukemia stem cells survival].

PubMed

Ding, Fei; Li, Jun-Min

2011-10-01

Tumor stem/progenitor cells are the cells with the characteristics of self-renewal, differentiating to all the other cell populations within tumor, which are also regarded as the source of tumor relapse, drug-resistance and metastasis. As a subtype of acute myeloid leukemia, acute promyelocytic leukemia (APL) represents the target of therapy due to the good response of the oncogenic protein PML-RARα to all-trans retinoic acid (ATRA) and arsenic trioxide (ATO). This review summarizes the latest research results of APL as follows: (1) there probably are two APL stem/progenitor cell populations within APL, and self-renewal and survival of APL stem/progenitor cells highly depend on PML-RARα expression, cell cycle inhibitor p21, self-renewal associated molecules and chemokines; and (2) ATRA and ATO eradicate APL stem/progenitor cells mainly by PML-RARα degradation, FOXO3A activation and the inhibition of self-renewal-associated signaling pathway of sonic hedgehog. These findings are helpful to improve other tumor therapy.

Perspectives on the Use of Stem Cells for Autism Treatment

PubMed Central

Bradstreet, James Jeffrey; Antonucci, Nicola

2013-01-01

Autism and autism spectrum disorders (ASDs) are complex neurodevelopmental disorders. ASDs are clinically defined by deficits in communication, social skills, and repetitive and/or restrictive interests and behaviours. With the prevalence rates for ASDs rapidly increasing, the need for effective therapies for autism is a priority for biomedical research. Currently available medications do not target the core symptoms, can have markedly adverse side-effects, and are mainly palliative for negative behaviours. The development of molecular and regenerative interventions is progressing rapidly, and medicine holds great expectations for stem cell therapies. Cells could be designed to target the observed molecular mechanisms of ASDs, that is, abnormal neurotransmitter regulation, activated microglia, mitochondrial dysfunction, blood-brain barrier disruptions, and chronic intestinal inflammation. Presently, the paracrine, secretome, and immunomodulatory effects of stem cells would appear to be the likely mechanisms of application for ASD therapeutics. This review will focus on the potential use of the various types of stem cells: embryonic, induced pluripotential, fetal, and adult stem cells as targets for ASD therapeutics. PMID:24222772

Requirement of myomaker-mediated stem cell fusion for skeletal muscle hypertrophy.

PubMed

Goh, Qingnian; Millay, Douglas P

2017-02-10

Fusion of skeletal muscle stem/progenitor cells is required for proper development and regeneration, however the significance of this process during adult muscle hypertrophy has not been explored. In response to muscle overload after synergist ablation in mice, we show that myomaker, a muscle specific membrane protein essential for myoblast fusion, is activated mainly in muscle progenitors and not myofibers. We rendered muscle progenitors fusion-incompetent through genetic deletion of myomaker in muscle stem cells and observed a complete reduction of overload-induced hypertrophy. This blunted hypertrophic response was associated with a reduction in Akt and p70s6k signaling and protein synthesis, suggesting a link between myonuclear accretion and activation of pro-hypertrophic pathways. Furthermore, fusion-incompetent muscle exhibited increased fibrosis after muscle overload, indicating a protective role for normal stem cell activity in reducing myofiber strain associated with hypertrophy. These findings reveal an essential contribution of myomaker-mediated stem cell fusion during physiological adult muscle hypertrophy.

Kidney repair using stem cells: myth or reality as a therapeutic option?

PubMed

Iwatani, Hirotsugu; Imai, Enyu

2010-01-01

The kidney has been considered a highly terminally differentiated organ of the body, and its proliferative potential is low, with the result that it has been thought of as a most unlikely organ for regeneration. From the structural point of view, the kidney is elaborately composed of many cell types that function as a tissue unit and not as individual cells, which also makes it more difficult to regenerate. However, in clinical settings, the kidney does have regenerative potential as seen in the recovery from acute kidney injury. The role of bone marrow-derived mesenchymal stromal cells may mainly be to produce humoral factors accelerating regeneration. The origin, localization and role of kidney stem cells are under investigation. We also discuss potential applications of embryonic stem cells and induced pluripotent stem cells in kidney regeneration.

Comparison study of moisture content, colour properties and essential oil compounds extracted by hydrodistillation and supercritical fluid extraction between stem and leaves of lemongrass (Cymbopogun citratus)

NASA Astrophysics Data System (ADS)

Kamaruddin, Shazlin; Mustapha, Wan Aida Wan; Haiyee, Zaibunnisa Abdul

2018-04-01

The objectives of this study were to compare the properties of moisture content, colour and essential oil compounds between stem and leaves of lemongrass (Cymbopogun citratus). The essential oil was extracted using two different methods which are hydrodistillation and supercritical fluid extraction (SFE). There was no significant difference of moisture content between stem and leaves of lemongrass. The lightness (L) and yellowness (+b) values of the stems were significantly higher (p<0.05) compared to the leaves. The highest yield of essential oil was obtained by extraction using supercritical fluid extraction (SFE) in leaves (˜ 0.7%) by treatment at 1700psi and 50°C. The main compound of extracted essential oil was citral (geranial and neral).

[Advances in application of clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 system in stem cells research].

PubMed

Sun, S J; Huo, J H; Geng, Z J; Sun, X Y; Fu, X B

2018-04-20

Gene engineering has attracted worldwide attention because of its ability of precise location of disease mutations in genome. As a new gene editing technology, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) system is simple, fast, and accurate to operate at a specific gene site. It overcomes the long-standing problem of conventional operation. At the same time, stem cells are a good foundation for establishing disease model in vitro. Therefore, it has great significance to combine stem cells with the rapidly developing gene manipulation techniques. In this review, we mainly focus on the mechanism of CRISPR/Cas9 technology and its application in stem cell genomic editing, so as to pave the way for promoting rapid application and development of CRISPR/Cas9 technology.

Main stem green and dry weights of red oak, white oak, and maple in the Appalachian region of Virginia

Treesearch

Richard G. Oderwald; Daniel A. Yaussy

1980-01-01

New emphasis has been placed on the weight of whole trees and portions of trees. Weight inventories and purchase of wood by weight are becoming increasingly common for saw logs as well as pulpwood. More information needs to be gathered on the weight of portions of tree stems, however, before weight can be a standard measurement unit. This information must also be...

Acute total left main stem occlusion treated with emergency percutaneous coronary intervention

PubMed Central

Mozid, A M; Sritharan, K; Clesham, G J

2010-01-01

Acute total occlusion of the left main stem (LMS) is a rare cause of myocardial infarction but carries a high risk of morbidity and mortality including presentation as sudden death. We describe the case of a 68-year-old woman who presented acutely with chest pain and ST segment elevation in lead aVR on her ECG suggestive of possible LMS occlusion. Emergency coronary angiography confirmed acute total LMS occlusion as well as an anomalous dominant right coronary artery. The patient underwent emergency percutaneous coronary intervention of the LMS with a good angiographic result and resolution of her symptoms. The patient was treated for acute left ventricular failure but made a gradual recovery and was discharged home 7 days after admission.

LANDSCAPE CHANGES IN A LOWLAND IN BENIN: ECOLOGICAL IMPACT ON PESTS AND NATURAL ENEMIES.

PubMed

Boucher, A; Silvie, P; Menozzi, P; Adda, C; Auzoux, S; Jean, J; Huat, J

2015-01-01

Habitat management involving conservative biological control could be a good crop pest management option in poor African countries. A survey was conducted from August 2013 to July 2014 in a rainfed lowland region near Pélébina, northern Benin, in order to characterize spatiotemporal landscape changes and investigate their influence on the main crop pests and their associated natural enemies. The area was mapped mainly regarding crop fields and fallows. Visual observations were recorded and a database was compiled. Major landscape composition changes were noted between rainy and dry seasons, which affected the presence of both pests and natural enemies. Cereals (rice, maize and sorghum) and cotton were grown in the humid season, and then okra (Abelmoschus esculentus) was the dominant vegetable crop in dry season. These modifications impacted fallow abundance throughout the lowland. Different cotton (e.g. Helicoverpa armigera, Dysdercus sp., Zonocerus variegatus) or rice (e.g. Diopsis longicornis, D. apicalis) pests were observed during dry season in okra crops. Dry season surveys of Poaceae in two types of fallows ('humid', 'dry') revealed the presence of very few stem borers: only 0.04% of stems sampled were infested by stem borers, with a mean of 1.13 larvae per stem. Known cereal stem borer species such as Busseola fusco, Coniesta ignefusalis, Sesamia calamistis were not clearly identified among these larvae because of their diapausing stage and white color. Unexpected pollinators (Hymenoptera Apidae, genus Braunsapis, Ceratina and Xylocopa) and predators (Crabronidae, genus Dasyproctus) were found in the stems. Sweep-net collection of insects in humid fallows allowed us to describe for the first time in Benin seven Diopsidae species (23% of adults bearing Laboulbeniomycetes ectoparasitic fungi). Some of these species were captured in rice fields during rainy season. Parasitoids (adult Chalcidoidae and Ichneumonoidae) were observed during both seasons but their impact on stem borers was hard to determine, even during the rainy season, due to their low abundance and the difficulty of identification. Predators (Reduviidae, Odonata) were found mainly in humid fallows and rice fields. Regarding our observations, we suggest the presence of alternate host crops such as okra during the dry season for rainy season crop pests. Moreover, fallows also had a real ecological role as a habitat resource for many guilds of insects (pollinators, pests, predators). The management of these landscape components should be the focus of a long-term study with the aim of enhancing pest management of rainy season crop pests.

Estimated survival probability of the Spotorno total hip arthroplasty after a 15- to 21-year follow-up: one surgeon's results.

PubMed

Terré, Ricardo A

2010-01-01

We retrospectively assess 171 consecutive total hip arthroplasties (THAs) with a Spotorno CLS uncemented prosthesis implanted through a Hardinge approach. The mean follow-up was 17.9 years. All consecutive operations were performed by 1 surgeon. Eight patients had been lost to follow-up, and 77 had died for unrelated causes. Overall, 4 stems and 19 cups underwent revision. The cumulative survival rate at 21 years was 79.02% (95% confidence interval [95% CI], 45.98-100.00%) for the acetabular component and 96.71% (95% CI, 60.71-100.00%) for the stem. We can conclude that failure of the Spotorno CLS THA is mainly due to its acetabular component (relative risk 4.5). Survival results for the Spotorno CLS stem exceed the patients? life expectancies in the 60- to 70-year-old population in our area. Loosening with or without fatigue fracture of the component and the learning curve for proper implantation have been the main causes for the expansion cup failure.

Regional HLA Differences in Poland and Their Effect on Stem Cell Donor Registry Planning

PubMed Central

Schmidt, Alexander H.; Solloch, Ute V.; Pingel, Julia; Sauter, Jürgen; Böhme, Irina; Cereb, Nezih; Dubicka, Kinga; Schumacher, Stephan; Wachowiak, Jacek; Ehninger, Gerhard

2013-01-01

Regional HLA frequency differences are of potential relevance for the optimization of stem cell donor recruitment. We analyzed a very large sample (n = 123,749) of registered Polish stem cell donors. Donor figures by 1-digit postal code regions ranged from n = 5,243 (region 9) to n = 19,661 (region 8). Simulations based on region-specific haplotype frequencies showed that donor recruitment in regions 0, 2, 3 and 4 (mainly located in the south-eastern part of Poland) resulted in an above-average increase of matching probabilities for Polish patients. Regions 1, 7, 8, 9 (mainly located in the northern part of Poland) showed an opposite behavior. However, HLA frequency differences between regions were generally small. A strong indication for regionally focused donor recruitment efforts can, therefore, not be derived from our analyses. Results of haplotype frequency estimations showed sample size effects even for sizes between n≈5,000 and n≈20,000. This observation deserves further attention as most published haplotype frequency estimations are based on much smaller samples. PMID:24069237

A systematic review on the role of environmental toxicants in stem cells aging.

PubMed

Hodjat, Mahshid; Rezvanfar, Mohammad Amin; Abdollahi, Mohammad

2015-12-01

Stem cells are an important target for environmental toxicants. As they are the main source for replenishing of organs in the body, any changes in their normal function could affect the regenerative potential of organs, leading to the appearance of age-related disease and acceleration of the aging process. Environmental toxicants could exert their adverse effect on stem cell function via multiple cellular and molecular mechanisms, resulting in changes in the stem cell differentiation fate and cell transformation, and reduced self-renewal capacity, as well as induction of stress-induced cellular senescence. The present review focuses on the effect of environmental toxicants on stem cell function associated with the aging process. We categorized environmental toxicants according to their preferred molecular mechanism of action on stem cells, including changes in genomic, epigenomic, and proteomic levels and enhancing oxidative stress. Pesticides, tobacco smoke, radiation and heavy metals are well-studied toxicants that cause stem cell dysfunction via induction of oxidative stress. Transgenerational epigenetic changes are the most important effects of a variety of toxicants on germ cells and embryos that are heritable and could affect health in the next several generations. A better understanding of the underlying mechanisms of toxicant-induced stem cell aging will help us to develop therapeutic intervention strategies against environmental aging. Meanwhile, more efforts are required to find the direct in vivo relationship between adverse effect of environmental toxicants and stem cell aging, leading to organismal aging. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mesenchymal Stem Cells Suppress Chronic Rejection in Heterotopic Small Intestine Transplant Rat Models Via Inhibition of CD68, Transforming Growth Factor- β1, and Platelet-Derived Growth Factor Expression.

PubMed

Li, Fuxin; Cao, Jisen; Zhao, Zhicheng; Li, Chuan; Qi, Feng; Liu, Tong

2017-04-01

Mesenchymal stem cells are easy to obtain and expand, with characteristics of low immunogenicity and strong tissue repair capacity. In this study, our aim was to investigate the role of mesenchymal stem cells in chronic immune rejection of heterotopic small intestine transplant in rats. After successfully constructing a rat chronic immune rejection model of heterotopic small intestine transplant, we infused mesenchymal stem cells into the animal recipients. We observed mesenchymal stem cell location in the recipients, recipient survival, pathology changes, and the expression of CD68, transforming growth factor β1, and platelet-derived growth factor C in the donor intestine. Mesenchymal stem cells inhibited the lymphocyte proliferation caused by concanavalin A in vitro. After stem cells were infused into recipients, they were mainly located in the donor intestine, as well as in the spleen and thymus. Recovery after transplant and pathology changes of the donor intestine in rats with stem cell infusion were better than in the control group; however, we observed no differences in survival time, accompanied by downregulated expression of CD68, transforming growth factor β1, and platelet-derived growth factor C. Mesenchymal stem cells, to a certain extent, could inhibit the process of chronic rejection. The mechanisms may include the inhibited function of these cells on lymphocyte proliferation, reduced infiltration of macrophages, and reduced expression of transforming growth factor β1 and platelet-derived growth factor C.

Identification of a novel putative pancreatic stem/progenitor cell marker DCAMKL-1 in normal mouse pancreas.

PubMed

May, Randal; Sureban, Sripathi M; Lightfoot, Stan A; Hoskins, Aimee B; Brackett, Daniel J; Postier, Russell G; Ramanujam, Rama; Rao, Chinthalapally V; Wyche, James H; Anant, Shrikant; Houchen, Courtney W

2010-08-01

Stem cells are critical in maintaining adult homeostasis and have been proposed to be the origin of many solid tumors, including pancreatic cancer. Here we demonstrate the expression patterns of the putative intestinal stem cell marker DCAMKL-1 in the pancreas of uninjured C57BL/6 mice compared with other pancreatic stem/progenitor cell markers. We then determined the viability of isolated pancreatic stem/progenitor cells in isotransplantation assays following DCAMKL-1 antibody-based cell sorting. Sorted cells were grown in suspension culture and injected into the flanks of athymic nude mice. Here we report that DCAMKL-1 is expressed in the main pancreatic duct epithelia and islets, but not within acinar cells. Coexpression was observed with somatostatin, NGN3, and nestin, but not glucagon or insulin. Isolated DCAMKL-1+ cells formed spheroids in suspension culture and induced nodule formation in isotransplantation assays. Analysis of nodules demonstrated markers of early pancreatic development (PDX-1), glandular epithelium (cytokeratin-14 and Ep-CAM), and isletlike structures (somatostatin and secretin). These data taken together suggest that DCAMKL-1 is a novel putative stem/progenitor marker, can be used to isolate normal pancreatic stem/progenitors, and potentially regenerates pancreatic tissues. This may represent a novel tool for regenerative medicine and a target for anti-stem cell-based therapeutics in pancreatic cancer.

Identification of a novel putative pancreatic stem/progenitor cell marker DCAMKL-1 in normal mouse pancreas

PubMed Central

May, Randal; Sureban, Sripathi M.; Lightfoot, Stan A.; Hoskins, Aimee B.; Brackett, Daniel J.; Postier, Russell G.; Ramanujam, Rama; Rao, Chinthalapally V.; Wyche, James H.; Anant, Shrikant

2010-01-01

Stem cells are critical in maintaining adult homeostasis and have been proposed to be the origin of many solid tumors, including pancreatic cancer. Here we demonstrate the expression patterns of the putative intestinal stem cell marker DCAMKL-1 in the pancreas of uninjured C57BL/6 mice compared with other pancreatic stem/progenitor cell markers. We then determined the viability of isolated pancreatic stem/progenitor cells in isotransplantation assays following DCAMKL-1 antibody-based cell sorting. Sorted cells were grown in suspension culture and injected into the flanks of athymic nude mice. Here we report that DCAMKL-1 is expressed in the main pancreatic duct epithelia and islets, but not within acinar cells. Coexpression was observed with somatostatin, NGN3, and nestin, but not glucagon or insulin. Isolated DCAMKL-1+ cells formed spheroids in suspension culture and induced nodule formation in isotransplantation assays. Analysis of nodules demonstrated markers of early pancreatic development (PDX-1), glandular epithelium (cytokeratin-14 and Ep-CAM), and isletlike structures (somatostatin and secretin). These data taken together suggest that DCAMKL-1 is a novel putative stem/progenitor marker, can be used to isolate normal pancreatic stem/progenitors, and potentially regenerates pancreatic tissues. This may represent a novel tool for regenerative medicine and a target for anti-stem cell-based therapeutics in pancreatic cancer. PMID:20522640

New insights into redox regulation of stem cell self-renewal and differentiation.

PubMed

Ren, Fenglian; Wang, Kui; Zhang, Tao; Jiang, Jingwen; Nice, Edouard Collins; Huang, Canhua

2015-08-01

Reactive oxygen species (ROS), the natural byproducts of aerobic metabolism, are precisely orchestrated to evoke diverse signaling pathways. To date, studies have focused mainly on the detrimental effects of ROS in stem cells. Recently, accumulating evidence has suggested that ROS also function as second messengers that modulate stem cell self-renewal and differentiation by regulating intricate signaling networks. Although many efforts have been made to clarify the general effects of ROS on signal transduction in stem cells, less is known about the initial and direct executors of ROS signaling, which are known as 'redox sensors'. Modifications of cysteine residues in redox sensors are of significant importance in the modulation of protein function in response to different redox conditions. Intriguingly, most key molecules in ROS signaling and cell cycle regulation (including transcriptional factors and kinases) that are crucial in the regulation of stem cell self-renewal and differentiation have the potential to be redox sensors. We highlight herein the importance of redox regulation of these key regulators in stem cell self-renewal and differentiation. Understanding the mechanisms of redox regulation in stem cell self-renewal and differentiation will open exciting new perspectives for stem cell biology. This article is part of a Special Issue entitled Redox regulation of differentiation and de-differentiation. Copyright © 2015 Elsevier B.V. All rights reserved.

Root biomechanics in Rhizophora mangle: anatomy, morphology and ecology of mangrove's flying buttresses.

PubMed

Méndez-Alonzo, Rodrigo; Moctezuma, Coral; Ordoñez, Víctor R; Angeles, Guillermo; Martínez, Armando J; López-Portillo, Jorge

2015-04-01

Rhizophora species of mangroves have a conspicuous system of stilt-like roots (rhizophores) that grow from the main stem and resemble flying buttresses. As such, the development of rhizophores can be predicted to be important for the effective transmission of dynamic loads from the top of the tree to the ground, especially where the substrate is unstable, as is often the case in the habitats where Rhizophora species typically grow. This study tests the hypothesis that rhizophore architecture in R. mangle co-varies with their proximity to the main stem, and with stem size and crown position. The allometry and wood mechanical properties of R. mangle (red mangrove) trees growing in a mangrove basin forest within a coastal lagoon in Mexico were compared with those of coexisting, non-buttressed mangrove trees of Avicennia germinans. The anatomy of rhizophores was related to mechanical stress due to crown orientation (static load) and to prevailing winds (dynamic load) at the study site. Rhizophores buttressed between 10 and 33 % of tree height. There were significant and direct scaling relationships between the number, height and length of rhizophores vs. basal area, tree height and crown area. Wood mechanical resistance was significantly higher in the buttressed R. mangle (modulus of elasticity, MOE = 18·1 ± 2 GPa) than in A. germinans (MOE = 12·1 ± 0·5 GPa). Slenderness ratios (total height/stem diameter) were higher in R. mangle, but there were no interspecies differences in critical buckling height. When in proximity to the main stem, rhizophores had a lower length/height ratio, higher eccentricity and higher xylem/bark and pith proportions. However, there were no directional trends with regard to prevailing winds or tree leaning. In comparison with A. germinans, a tree species with wide girth and flare at the base, R. mangle supports a thinner stem of higher mechanical resistance that is stabilized by rhizophores resembling flying buttresses. This provides a unique strategy to increase tree slenderness and height in the typically unstable substrate on which the trees grow, at a site that is subject to frequent storms. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

How Stem Cells Speak with Host Immune Cells in Inflammatory Brain Diseases

PubMed Central

Pluchino, Stefano; Cossetti, Chiara

2014-01-01

Advances in stem cell biology have raised great expectations that diseases and injuries of the central nervous system (CNS) may be ameliorated by the development of non-hematopoietic stem cell medicines. Yet, the application of adult stem cells as CNS therapeutics is challenging and the interpretation of some of the outcomes ambiguous. In fact, the initial idea that stem cell transplants work only via structural cell replacement has been challenged by the observation of consistent cellular signaling between the graft and the host. Cellular signaling is the foundation of coordinated actions and flexible responses, and arises via networks of exchanging and interacting molecules that transmit patterns of information between cells. Sustained stem cell graft-to-host communication leads to remarkable trophic effects on endogenous brain cells and beneficial modulatory actions on innate and adaptive immune responses in vivo, ultimately promoting the healing of the injured CNS. Among a number of adult stem cell types, mesenchymal stem cells (MSCs) and neural stem/precursor cells (NPCs) are being extensively investigated for their ability to signal to the immune system upon transplantation in experimental CNS diseases. Here, we focus on the main cellular signaling pathways that grafted MSCs and NPCs use to establish a therapeutically relevant cross talk with host immune cells, while examining the role of inflammation in regulating some of the bidirectionality of these communications. We propose that the identification of the players involved in stem cell signaling might contribute to the development of innovative, high clinical impact therapeutics for inflammatory CNS diseases. PMID:23633288

Retracted article: In vitro derivation of mammalian germ cells from stem cells and their potential therapeutic application.

PubMed

Saito, Shigeo; Lin, Ying-Chu; Murayama, Yoshinobu; Nakamura, Yukio; Eckner, Richard; Niemann, Heiner; Yokoyama, Kazunari K

2015-12-01

Pluripotent stem cells (PSCs) are a unique type of cells because they exhibit the characteristics of self-renewal and pluripotency. PSCs may be induced to differentiate into any cell type, even male and female germ cells, suggesting their potential as novel cell-based therapeutic treatment for infertility problems. Spermatogenesis is an intricate biological process that starts from self-renewal of spermatogonial stem cells (SSCs) and leads to differentiated haploid spermatozoa. Errors at any stage in spermatogenesis may result in male infertility. During the past decade, much progress has been made in the derivation of male germ cells from various types of progenitor stem cells. Currently, there are two main approaches for the derivation of functional germ cells from PSCs, either the induction of in vitro differentiation to produce haploid cell products, or combination of in vitro differentiation and in vivo transplantation. The production of mature and fertile spermatozoa from stem cells might provide an unlimited source of autologous gametes for treatment of male infertility. Here, we discuss the current state of the art regarding the differentiation potential of SSCs, embryonic stem cells, and induced pluripotent stem cells to produce functional male germ cells. We also discuss the possible use of livestock-derived PSCs as a novel option for animal reproduction and infertility treatment.

Mesenchymal Stem Cells Improve Motor Functions and Decrease Neurodegeneration in Ataxic Mice

PubMed Central

Jones, Jonathan; Estirado, Alicia; Redondo, Carolina; Pacheco-Torres, Jesus; Sirerol-Piquer, Maria-Salomé; Garcia-Verdugo, José M; Martinez, Salvador

2015-01-01

The main objective of this work is to demonstrate the feasibility of using bone marrow-derived stem cells in treating a neurodegenerative disorder such as Friedreich's ataxia. In this disease, the dorsal root ganglia of the spinal cord are the first to degenerate. Two groups of mice were injected intrathecally with mesenchymal stem cells isolated from either wild-type or Fxntm1Mkn/Tg(FXN)YG8Pook (YG8) mice. As a result, both groups presented improved motor skills compared to nontreated mice. Also, frataxin expression was increased in the dorsal root ganglia of the treated groups, along with lower expression of the apoptotic markers analyzed. Furthermore, the injected stem cells expressed the trophic factors NT3, NT4, and BDNF, which bind to sensory neurons of the dorsal root ganglia and increase their survival. The expression of antioxidant enzymes indicated that the stem cell-treated mice presented higher levels of catalase and GPX-1, which are downregulated in the YG8 mice. There were no significant differences in the use of stem cells isolated from wild-type and YG8 mice. In conclusion, bone marrow mesenchymal stem cell transplantation, both autologous and allogeneic, is a feasible therapeutic option to consider in delaying the neurodegeneration observed in the dorsal root ganglia of Friedreich's ataxia patients. PMID:25070719

Placental-derived stem cells: Culture, differentiation and challenges

PubMed Central

Oliveira, Maira S; Barreto-Filho, João B

2015-01-01

Stem cell therapy is a promising approach to clinical healing in several diseases. A great variety of tissues (bone marrow, adipose tissue, and placenta) are potentially sources of stem cells. Placenta-derived stem cells (p-SCs) are in between embryonic and mesenchymal stem cells, sharing characteristics with both, such as non-carcinogenic status and property to differentiate in all embryonic germ layers. Moreover, their use is not ethically restricted as fetal membranes are considered medical waste after birth. In this context, the present review will be focused on the biological properties, culture and potential cell therapy uses of placental-derived stem cells. Immunophenotype characterization, mainly for surface marker expression, and basic principles of p-SC isolation and culture (mechanical separation or enzymatic digestion of the tissues, the most used culture media, cell plating conditions) will be presented. In addition, some preclinical studies that were performed in different medical areas will be cited, focusing on neurological, liver, pancreatic, heart, muscle, pulmonary, and bone diseases and also in tissue engineering field. Finally, some challenges for stem cell therapy applications will be highlighted. The understanding of the mechanisms involved in the p-SCs differentiation and the achievement of pure cell populations (after differentiation) are key points that must be clarified before bringing the preclinical studies, performed at the bench, to the medical practice. PMID:26029347

Bone preserving level of osteotomy in short-stem total hip arthroplasty does not influence stress shielding dimensions - a comparing finite elements analysis.

PubMed

Burchard, Rene; Braas, Sabrina; Soost, Christian; Graw, Jan Adriaan; Schmitt, Jan

2017-08-07

The main objective of every new development in total hip arthroplasty (THA) is the longest possible survival of the implant. Periprosthetic stress shielding is a scientifically proven phenomenon which leads to inadvertent bone loss. So far, many studies have analysed whether implanting different hip stem prostheses result in significant preservation of bone stock. The aim of this preclinical study was to investigate design-depended differences of the stress shielding effect after implantation of a selection of short-stem THA-prostheses that are currently available. Based on computerised tomography (CT), a finite elements (FE) model was generated and a virtual THA was performed with different stem designs of the implant. Stems were chosen by osteotomy level at the femoral neck (collum, partial collum, trochanter sparing, trochanter harming). Analyses were performed with previously validated FE models to identify changes in the strain energy density (SED). In the trochanteric region, only the collum-type stem demonstrated a biomechanical behaviour similar to the native femur. In contrast, no difference in biomechanical behaviour was found between partial collum, trochanter harming and trochanter sparing models. All of the short stem-prostheses showed lower stress-shielding than a standard stem. Based on the results of this study, we cannot confirm that the design of current short stem THA-implants leads to a different stress shielding effect with regard to the level of osteotomy. Somehow unexpected, we found a bone stock protection in metadiaphyseal bone by simulating a more distal approach for osteotomy. Further clinical and biomechanical research including long-term results is needed to understand the influence of short-stem THA on bone remodelling and to find the optimal stem-design for a reduction of the stress shielding effect.

Stem cells for kidney repair: useful tool for acute renal failure?

PubMed

Yokoo, Takashi; Kawamura, Tetsuya; Kobayashi, Eiji

2008-10-01

Several cell types isolated from adult tissues have been reported to differentiate into mature kidney cells that may participate in renal repair after systemic administration. Chen et al. report that local mesenchymal stem cells derived from adult mouse kidneys are another source of cells with similar properties. Although these cells have the potential to differentiate into endothelial-lineage cell types, their therapeutic benefit to the ischemic kidney is mainly via the production of renoprotective factors.

The Alliance of Mesenchymal Stem Cells, Bone, and Diabetes

PubMed Central

Napoli, Nicola; Paladini, Angela; Briganti, Silvia I.; Pozzilli, Paolo; Epstein, Sol

2014-01-01

Bone fragility has emerged as a new complication of diabetes. Several mechanisms in diabetes may influence bone homeostasis by impairing the action between osteoblasts, osteoclasts, and osteocytes and/or changing the structural properties of the bone tissue. Some of these mechanisms can potentially alter the fate of mesenchymal stem cells, the initial precursor of the osteoblast. In this review, we describe the main factors that impair bone health in diabetic patients and their clinical impact. PMID:25140176

First report of pediatric hematopoietic stem cell transplantation activities in the eastern mediterranean region from 1984 to 2011: on behalf of the pediatric cancer working committee of the eastern mediterranean blood and marrow transplantation group.

PubMed

Hussein, A A; Hamidieh, A A; Elhaddad, A; Ramzi, M; Othman, T B; Hussain, F; Dennison, D; Ahmed, P; Abboud, M; Al-Ahmari, A; Wahadneh, A; Fathy, J; Bekadja, M-A; Al-Kindi, S; Benchekroun, S; Ibrahim, A; Behfar, M; Samra, M; Ladeb, S; Adil, S; El-Solh, H; Ayas, M; Aljurf, M; Ghavamzadeh, A; Al-Seraihy, A

2017-01-01

To describe the hematopoietic stem cell transplantation (HSCT) activities for children in the Eastern Mediterranean (EM) region, data on transplants performed for children less than 18 years of age between 1984 and 2011 in eight EM countries (Egypt, Iran, Jordan, Lebanon, Oman, Pakistan, Saudi Arabia and Tunisia) were collected. A total of 5187 transplants were performed, of which 4513 (87%) were allogeneic and 674 (13%) were autologous. Overall, the indications for transplantation were malignant diseases in 1736 (38.5%) and non-malignant in 2777 (61.5%) patients. A myeloablative conditioning regimen was used in 88% of the allografts. Bone marrow (BM) was the most frequent source of stem cells (56.2%), although an increasing use of PBSC was observed in the last decade. The stem cell source of autologous HSCT has shifted over time from BM to PBSC, and 80.9% of autologous HSCTs were from PBSCs. The donors for allogeneic transplants were matched-related in 94.5% of the cases, and unrelated transplants, mainly cord blood (99%) in 239 (5.5%) cases. This is the first report to describe the pediatric HSCT activities in EM countries. Non-malignant disorders are the main indication for allogeneic transplantation. Frequency of alternate donor transplantation is low.

Pyruvate dehydrogenase expression is negatively associated with cell stemness and worse clinical outcome in prostate cancers

PubMed Central

Zhong, Yali; Li, Xiaoli; Ji, Yasai; Li, Xiaoran; Li, Yaqing; Yu, Dandan; Yuan, Yuan; Liu, Jian; Li, Huixiang; Zhang, Mingzhi; Ji, Zhenyu; Fan, Dandan; Wen, Jianguo; Goscinski, Mariusz Adam; Yuan, Long; Hao, Bin; Nesland, Jahn M; Suo, Zhenhe

2017-01-01

Cells generate adenosine-5′-triphosphate (ATP), the major currency for energy-consuming reactions, through mitochondrial oxidative phosphorylation (OXPHOS) and glycolysis. One of the remarkable features of cancer cells is aerobic glycolysis, also known as the “Warburg Effect”, in which cancer cells rely preferentially on glycolysis instead of mitochondrial OXPHOS as the main energy source even in the presence of high oxygen tension. One of the main players in controlling OXPHOS is the mitochondrial gatekeeperpyruvate dehydrogenase complex (PDHc) and its major subunit is E1α (PDHA1). To further analyze the function of PDHA1 in cancer cells, it was knock out (KO) in the human prostate cancer cell line LnCap and a stable KO cell line was established. We demonstrated that PDHA1 gene KO significantly decreased mitochondrial OXPHOS and promoted anaerobic glycolysis, accompanied with higher stemness phenotype including resistance to chemotherapy, enhanced migration ability and increased expression of cancer stem cell markers. We also examined PDHA1 protein expression in prostate cancer tissues by immunohistochemistry and observed that reduced PDHA1 protein expression in clinical prostate carcinomas was significantly correlated with poor prognosis. Collectively, our results show that negative PDHA1 gene expressionis associated with significantly higher cell stemness in prostate cancer cells and reduced protein expression of this gene is associated with shorter clinical outcome in prostate cancers. PMID:28076853

Lower Permian stems as fluvial paleocurrent indicators of the Parnaíba Basin, northern Brazil

NASA Astrophysics Data System (ADS)

Capretz, Robson Louiz; Rohn, Rosemarie

2013-08-01

A comprehensive biostratinomic study was carried out with abundant stems from the Lower Permian Motuca Formation of the intracratonic Parnaíba Basin, central-north Brazil. The fossils represent a rare tropical to subtropical paleofloristic record in north Gondwana. Tree ferns dominate the assemblages (mainly Tietea, secondarily Psaronius), followed by gymnosperms, sphenophytes, other ferns and rare lycophytes. They are silica-permineralized, commonly reach 4 m length (exceptionally more than 10 m), lie loosely on the ground or are embedded in the original sandstone or siltstone matrix, and attract particular attention because of their frequent parallel attitudes. Many tree fern stems present the original straight cylindrical to slightly conical forms, other are somewhat flattened, and the gymnosperm stems are usually more irregular. Measurements of stem orientations and dimensions were made in three sites approximately aligned in a W-E direction in a distance of 27.3 km at the conservation unit "Tocantins Fossil Trees Natural Monument". In the eastern site, rose diagrams for 54 stems indicate a relatively narrow azimuthal range to SE. These stems commonly present attached basal bulbous root mantles and thin cylindrical sandstone envelopes, which sometimes hold, almost adjacent to the lateral stem surface, permineralized fern pinnae and other small plant fragments. In the more central site, 82 measured stems are preferentially oriented in the SW-NE direction, the proportion of gymnosperms is higher and cross-stratification sets of sandstones indicate paleocurrents mainly to NE and secondarily to SE. In the western site, most of the 42 measured stems lie in E-W positions. The predominantly sandy succession, where the fossil stems are best represented, evidences a braided fluvial system under semiarid conditions. The low plant diversity, some xeromorphic features and the supposedly almost syndepositional silica impregnation of the plants are coherent with marked dry seasons. Thick mudstones and some coquinites below and above the sandy interval may represent lacustrine facies formed in probably more humid conditions. The taphonomic history of the preserved plants began with exceptional storms that caused fast-flowing high water in channels and far into the floodplains. In the eastern site region, many tree ferns only fell, thus sometimes covering and protecting plant litter and leaves from further fragmentation. Assemblages of the central and western sites suggest that the trees were uprooted and transported in suspension (floating) parallel to the flow. Heavier ends of stems (according to their form or because of attached basal bulbous root mantle or large apical fronds) were oriented to upstream because of inertial forces. During falling water stage, the stems were stranded on riverbanks, usually maintaining the previous transport orientation, and were slightly buried. The perpendicular or oblique positions of some stems may have been caused by interference with other stems or shallow bars. Rare observed stems were apparently waterlogged before the final depositional process and transported as bedload. The differences of interpreted channel orientations between the three sites are expected in a braided fluvial system, considering the very low gradients of the basin and the work scale in the order of tens of kilometers. The mean direction of the drainage probably was to east and the flows apparently became weaker downstream. This study seems to provide reliable data for paleocurrent interpretations, especially considering areas with scarce preserved sedimentary structures.

Ohio River main stem study - The role of geographic information systems and remote sensing in flood damage assessments

NASA Technical Reports Server (NTRS)

Edwardo, H. A.; Moulis, F. R.; Merry, C. J.; Mckim, H. L.; Kerber, A. G.; Miller, M. A.

1985-01-01

The Pittsburgh District, Corps of Engineers, has conducted feasibility analyses of various procedures for performing flood damage assessments along the main stem of the Ohio River. Procedures using traditional, although highly automated, techniques and those based on geographic information systems have been evaluated at a test site, the City of New Martinsville, Wetzel County, WV. The flood damage assessments of the test site developed from an automated, conventional structure-by-structure appraisal served as the ground truth data set. A geographic information system was developed for the test site which includes data on hydraulic reach, ground and reference flood elevations, and land use/cover. Damage assessments were made using land use mapping developed from an exhaustive field inspection of each tax parcel. This ground truth condition was considered to provide the best comparison of flood damages to the conventional approach. Also, four land use/cover data sets were developed from Thematic Mapper Simulator (TMS) and Landsat-4 Thematic Mapper (TM) data. One of these was also used to develop a damage assessment of the test site. This paper presents the comparative absolute and relative accuracies of land use/cover mapping and flood damage assessments, and the recommended role of geographic information systems aided by remote sensing for conducting flood damage assessments and updates along the main stem of the Ohio River.

The distribution of phosphorus in Popes Creek, VA, and in the Pocomoke River, MD: Two watersheds with different land management practices in the Chesapeake Bay Basin

USGS Publications Warehouse

Simon, N.S.; Bricker, O.P.; Newell, W.; McCoy, J.; Morawe, R.

2005-01-01

This paper compares phosphorus (P) concentrations in sediments from two watersheds, one with, and one without, intensive animal agriculture. The watersheds are in the coastal plain of the Chesapeake Bay and have similar physiographic characteristics. Agriculture in the Pocomoke River, MD, watershed supplied 2.7 percent of all broiler chickens produced in the USA in 1997. Poultry litter is an abundant, local source of manure for crops. Broiler chickens are not produced in the Popes Creek, VA, watershed and poultry manure is, therefore, not a major source of fertilizer. The largest concentrations of P in sediment samples are found in floodplain and main-stem bottom sediment in both watersheds. Concentrations of total P and P extracted with 1N HCl are significantly larger in main-stem bottom sediments from the Pocomoke River than in main-stem bottom sediments from Popes Creek. Larger concentrations of P are associated with what are potentially redox sensitive iron oxyhydroxides in sediment samples from the Pocomoke River watershed than are associated with what are potentially redox sensitive iron oxyhydroxides in sediment samples from the Popes Creek watershed. Data for P and iron (Fe) concentrations in sediments from the Popes Creek watershed provide a numerical framework (baseline) with which to compare P and Fe concentrations in sediment from the Pocomoke River watershed. ?? Springer 2005.

Stem Cells and Regenerative Medicine: Myth or Reality of the 21th Century

PubMed Central

Stoltz, J.-F.; de Isla, N.; Li, Y. P.; Bensoussan, D.; Zhang, L.; Huselstein, C.; Chen, Y.; Decot, V.; Magdalou, J.; Li, N.; Reppel, L.; He, Y.

2015-01-01

Since the 1960s and the therapeutic use of hematopoietic stem cells of bone marrow origin, there has been an increasing interest in the study of undifferentiated progenitors that have the ability to proliferate and differentiate into various tissues. Stem cells (SC) with different potency can be isolated and characterised. Despite the promise of embryonic stem cells, in many cases, adult or even fetal stem cells provide a more interesting approach for clinical applications. It is undeniable that mesenchymal stem cells (MSC) from bone marrow, adipose tissue, or Wharton's Jelly are of potential interest for clinical applications in regenerative medicine because they are easily available without ethical problems for their uses. During the last 10 years, these multipotent cells have generated considerable interest and have particularly been shown to escape to allogeneic immune response and be capable of immunomodulatory activity. These properties may be of a great interest for regenerative medicine. Different clinical applications are under study (cardiac insufficiency, atherosclerosis, stroke, bone and cartilage deterioration, diabetes, urology, liver, ophthalmology, and organ's reconstruction). This review focuses mainly on tissue and organ regeneration using SC and in particular MSC. PMID:26300923

Cell wall proteome analysis of Arabidopsis thaliana mature stems.

PubMed

Duruflé, Harold; Clemente, Hélène San; Balliau, Thierry; Zivy, Michel; Dunand, Christophe; Jamet, Elisabeth

2017-04-01

Plant stems carry flowers necessary for species propagation and need to be adapted to mechanical disturbance and environmental factors. The stem cell walls are different from other organs and can modify their rigidity or viscoelastic properties for the integrity and the robustness required to withstand mechanical impacts and environmental stresses. Plant cell wall is composed of complex polysaccharide networks also containing cell wall proteins (CWPs) crucial to perceive and limit the environmental effects. The CWPs are fundamental players in cell wall remodeling processes, and today, only 86 have been identified from the mature stems of the model plant Arabidopsis thaliana. With a destructive method, this study has enlarged its coverage to 302 CWPs. This new proteome is mainly composed of 27.5% proteins acting on polysaccharides, 16% proteases, 11.6% oxido-reductases, 11% possibly related to lipid metabolism and 11% of proteins with interacting domains with proteins or polysaccharides. Compared to stem cell wall proteomes already available (Brachypodium distachyon, Sacharum officinarum, Linum usitatissimum, Medicago sativa), that of A. thaliana stems has a higher proportion of proteins acting on polysaccharides and of proteases, but a lower proportion of oxido-reductases. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cancer stem cell-targeted therapeutics and delivery strategies.

PubMed

Ahmad, Gulzar; Amiji, Mansoor M

2017-08-01

Cancer initiating or stem cells (CSCs) are a small population of cells in the tumor mass, which have been reported to be present in different types of cancers. CSCs usually reside within the tumor and are responsible for reoccurrence of cancer. The imprecise, inaccessible nature and increased efflux of conventional therapeutic drugs make these cells resistant to drugs. We discuss the specific markers for identification of these cells, role of CSCs in chemotherapy resistance and use of different therapeutic means to target them, including elucidation of specific cell markers, exploitation of different signaling pathways and use of nanotechnology. Area covered: This review covers cancer stem cell signaling which are used by these cells to maintain their quiescence, stemness and resistant phenotype, distinct cell surface markers, contribution of these cells in drug resistance, inevitability to cure cancer and use of nanotechnology to overcome this hurdle. Expert opinion: Cancer stem cells are the main culprit of our failure to cure cancer. In order to cure cancer along with other cells types in cancer, cancer stem cells need to be targeted in the tumor bed. Nanotechnology solutions can facilitate clinical translation of the therapeutics along with other emerging technologies to cure cancer.

Human Embryonic Stem Cell Therapy in Crohn's Disease: A Case Report.

PubMed

Shroff, Geeta

2016-02-29

Crohn's disease is a chronic inflammatory disease of the intestines, mainly the colon and ileum, related with ulcers and fistulae. It is estimated to affect 565,000 people in the United States. Currently available therapies, such as antibiotics, thiopurines, and anti-tumor necrosis factor-alpha agents, are only observed to reduce the complications associated with Crohn's disease and to improve quality of life, but cannot cure the disease. Stem cell therapy appears to have certain advantages over conventional therapies. Our study aimed to evaluate the efficacy of human embryonic stem cell therapy in a patient with Crohn's disease. A 21-year-old male with chief complaints of intolerance to specific foods, abdominal pain, and diarrhea underwent human embryonic stem cell therapy for two months. After undergoing human embryonic stem cell therapy, the patient showed symptomatic relief. He had no complaints of back pain, abdominal pain, or diarrhea and had improved digestion. The patient had no signs and symptoms of skin infection, and had improved limb stamina, strength, and endurance. The condition of patient was stable after the therapy. Human embryonic stem cell therapy might serve as a new optimistic treatment approach for Crohn's disease.

Effects of irradiation on stem cell response to differentiation inhibitors in the Planarian Dugesia etrusca

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steele, V.E.; Lange, C.S.

1976-07-01

The planarian owes its extensive powers of regeneration to the possession of a totipotential stem cell system. The survival of the animal after irradiation depends mainly upon this system. In this respect the planarian is analogous to mammalian organ systems such as bone marrow or gut epithelium. The differentiated cells control the course of stem cell mediated tissue renewal by the secretion of differentiator and/or inhibitor substances. One such inhibitor substance, present in extracts prepared from homogenized whole planarians, specifically inhibits brain formation. This substance is organ specific, but not species specific. The differentiative integrity of the stem cells aftermore » irradiation is measured by comparing the regenerated brain volumes resulting from the presence or absence of the brain inhibitory extract during the regeneration period. Our data suggest that increasing doses of x irradiation decreases the ability of the stem cells to respond to differentiative substances. The data presented also explore the possibility of altering the postirradiation recovery pattern by shifting the differentiative demands placed on the stem cells. The final proportions of animals (one-half regenerated with, and one-half without, the extract) surviving after 60 days were not significantly different.« less

Matched unrelated donor transplants-State of the art in the 21st century.

PubMed

Altaf, Syed Y; Apperley, Jane F; Olavarria, Eduardo

2016-10-01

Hematopoietic stem cell transplantation (HSCT) is the therapy of choice in many hematological malignant and non-malignant diseases by using human leukocyte antigen (HLA)-matched siblings as stem cell source but only one third of the patients will have HLA-matched siblings. Hence, physicians rely on the availability of matched unrelated donors (URD). The possibility of finding a matched URD is now more than 70% due to continuous expansion of URD registries around the world. The use of URD in adult patients is steadily increasing and in the last 8 years has superseded the numbers of matched sibling donor transplants and has become the most commonly used stem cell source. There is also an increasing trend to use peripheral blood (PB) stem cells rather than bone marrow (BM) stem cells. Outcomes following URD transplants depend mainly upon the indication and urgency of transplant, age and comorbidities of recipients, cytomegalovirus (CMV) matching/mismatching between donor and the recipient, and degree of HLA matching. In some studies outcome of unrelated stem cell transplants in terms of treatment-related mortality (TRM), disease-free survival (DFS), and overall survival (OS) is comparable to sibling donors. Copyright © 2016 Elsevier Inc. All rights reserved.

Rapid Rapamycin-Only Induced Osteogenic Differentiation of Blood-Derived Stem Cells and Their Adhesion to Natural and Artificial Scaffolds

PubMed Central

Eliana, Cozzoli; Flavio, Acri; Marco, Ranalli; Giacomo, Diedenhofen

2017-01-01

Stem cells are a centerpiece of regenerative medicine research, and the recent development of adult stem cell-based therapy systems has vigorously expanded the scope and depth of this scientific field. The regeneration of damaged and/or degraded bone tissue in orthopedic, dental, or maxillofacial surgery is one of the main areas where stem cells and their regenerative potential could be used successfully, requiring tissue engineering solutions incorporating an ideal stem cell type paired with the correct mechanical support. Our contribution to this ongoing research provides a new model of in vitro osteogenic differentiation using blood-derived stem cells (BDSCs) and rapamycin, visibly expressing typical osteogenic markers within ten days of treatment. In depth imaging studies allowed us to observe the adhesion, proliferation, and differentiation of BDSCs to both titanium and bone scaffolds. We demonstrate that BDSCs can differentiate towards the osteogenic lineage rapidly, while readily adhering to the scaffolds we exposed them to. Our results show that our model can be a valid tool to study the molecular mechanisms of osteogenesis while tailoring tissue engineering solutions to these new insights. PMID:28814956

Chemical compositions and antibacterial activity of the leaf and stem oils of Piper porphyrophyllum (Lindl.) N.E. Br.

PubMed Central

Salleh, Wan Mohd Nuzul Hakimi Wan; Ahmad, Farediah; Sirat, Hasnah Mohd; Yen, Khong Heng

2012-01-01

The essential oils obtained by hydrodistillation from the fresh leaf and stem of Piper porphyrophyllum N.E. Br. were analyzed by GC and GC/MS. Thirty four constituents were identified in the leaf oil, while thirty eight constituents were identified in the stems oil. The most abundant components in the leaf oil included bicyclogermacrene (14.7 %), α-copaene (13.2 %) and β-phellandrene (9.5 %) while sabinene (15.5 %), bicyclogermacrene (12.3 %) and α-copaene (8.1 %) were the main constituents in the stem oil. The evaluation of antibacterial activity by using micro-dilution method revealed that both oils were moderately active against all the Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis) and Gram-negative bacteria (Pseudomonas aeruginosa, Pseudomonas putida and Escherichia coli) with minimum inhibitory concentration (MIC) values in the range 125-1000 µg/ml. PMID:27418915

[Research Progress on Metabolic Regulatory Mechanisms of Hematopoietic Stem Cells -Review].

PubMed

Zhang, Ya-Wen; Cheng, Hui; Cheng, Tao

2018-06-01

Hematopoietic stem cells (HSC) are a class of stem cells with self-renewal and multipotent differentiation into a variety of blood cells and are most thoroughly studied, maturely applied in the clinic adult stem cell. Function of HSC is closely associated with metabolic regulation. The metabolic state mainly maintains HSC living in hypoxic bone marrow microenvironment depending on glycolysis for energy metabolism, and keeping low reactive oxygen species (ROS) level. Proteins like Hif-1, FoxO3, ATM, PTPMT1 protect HSC from ROS injury, maintaining HSC in hypoxic state. In addition, glucose metabolism-related enzymes, glutamine, fatty acid oxidation, purine and amino acid metabolism also play important roles in metabolic regulation of HSC. In this review the research progress on metabolism regnlation mechanisms of HSC is summurized, focusing on the mechanisms releted with oxydation metabolism regulation, carbohydrate metabolism level, purine metabolism and aminoacide metabolism.

Stem cells as biological heart pacemakers.

PubMed

Gepstein, Lior

2005-12-01

Abnormalities in the pacemaker function of the heart or in cardiac impulse conduction may result in the appearance of a slow heart rate, traditionally requiring the implantation of a permanent electronic pacemaker. In recent years, a number of experimental approaches have been developed in an attempt to generate biological alternatives to implantable electronic devices. These strategies include, initially, a number of gene therapy approaches (aiming to manipulate the expression of ionic currents or their modulators and thereby convert quiescent cardiomyocytes into pacemaking cells) and, more recently, the use of cell therapy and tissue engineering. The latter approach explored the possibility of grafting pacemaking cells, either derived directly during the differentiation of human embryonic stem cells or engineered from mesenchymal stem cells, into the myocardium. This review will describe each of these approaches, focusing mainly on the stem cell strategies, their possible advantages and shortcomings, as well as the avenues required to make biological pacemaking a clinical reality.

Self-assembled dual-modality contrast agents for non-invasive stem cell tracking via near-infrared fluorescence and magnetic resonance imaging.

PubMed

Liu, Hong; Tan, Yan; Xie, Lisi; Yang, Lei; Zhao, Jing; Bai, Jingxuan; Huang, Ping; Zhan, Wugen; Wan, Qian; Zou, Chao; Han, Yali; Wang, Zhiyong

2016-09-15

Stem cells hold great promise for treating various diseases. However, one of the main drawbacks of stem cell therapy is the lack of non-invasive image-tracking technologies. Although magnetic resonance imaging (MRI) and near-infrared fluorescence (NIRF) imaging have been employed to analyse cellular and subcellular events via the assistance of contrast agents, the sensitivity and temporal resolution of MRI and the spatial resolution of NIRF are still shortcomings. In this study, superparamagnetic iron oxide nanocrystals and IR-780 dyes were co-encapsulated in stearic acid-modified polyethylenimine to form a dual-modality contrast agent with nano-size and positive charge. These resulting agents efficiently labelled stem cells and did not influence the cellular viability and differentiation. Moreover, the labelled cells showed the advantages of dual-modality imaging in vivo. Copyright © 2016 Elsevier Inc. All rights reserved.

Integrating independent research into science curricula to foster STEM leadership

NASA Astrophysics Data System (ADS)

Queenan, Craig; Calabro, Alyssa; Becker, David

2013-05-01

Preparing students for college and future careers is one of the main goals of K-12 education, but current STEM teaching methods do not do enough to interest students and leave them prepared to enter into and succeed in STEM careers. While measures to implement unifying standards for science education across the country are aimed at ensuring that all students are taught the same material at each grade level, a shift in the way science is taught to is needed to complete the redesign of science education. The independent research model described here aligns with the new content standards and focuses on developing the principles of perspective, purpose, resources, collaboration, analysis, and presentation. These principles not only engage students in the classroom, but also leave students prepared to enter into science programs in college and succeed in leadership roles in the STEM workforce.

Growth factors, stem cells and bronchopulmonary dysplasia.

PubMed

Alphonse, Rajesh S; Thébaud, Bernard

2011-01-01

Bronchopulmonary dysplasia (BPD) is the chronic lung disease of prematurity mainly affecting preterm infants that are born at 24-28 weeks of gestation. Surfactant therapy, antenatal steroids and incremental improvements in perinatal care have modified the pattern of injury and allowed survival of ever more immature infants, but there is still no specific treatment for BPD. As a consequence, this disorder remains the most common complication of extreme prematurity. Arrested alveolar growth and disrupted vasculogenesis, the histological hallmarks of BPD, may persist beyond childhood and lead to chronic lung diseases in adults. Recent advances in our understanding of stem cells and their potential to repair damaged organs offer the possibility for cell-based treatment for intractable diseases. This review summarizes basic concepts of stem cell biology and discusses the recent advances and challenges of stem cell-based therapies for lung diseases, with a particular focus on BPD. Copyright © 2011 S. Karger AG, Basel.

Limbal Stem Cell Deficiency and Treatment with Stem Cell Transplantation.

PubMed

Barut Selver, Özlem; Yağcı, Ayşe; Eğrilmez, Sait; Gürdal, Mehmet; Palamar, Melis; Çavuşoğlu, Türker; Ateş, Utku; Veral, Ali; Güven, Çağrı; Wolosin, Jose Mario

2017-10-01

The cornea is the outermost tissue of the eye and it must be transparent for the maintenance of good visual function. The superficial epithelium of the cornea, which is renewed continuously by corneal stem cells, plays a critical role in the permanence of this transparency. These stem cells are localized at the cornea-conjunctival transition zone, referred to as the limbus. When this zone is affected/destroyed, limbal stem cell deficiency ensues. Loss of limbal stem cell function allows colonization of the corneal surface by conjunctival epithelium. Over 6 million people worldwide are affected by corneal blindness, and limbal stem cell deficiency is one of the main causes. Fortunately, it is becoming possible to recover vision by autologous transplantation of limbal cells obtained from the contralateral eye in unilateral cases. Due to the potential risks to the donor eye, only a small amount of tissue can be obtained, in which only 1-2% of the limbal epithelial cells are actually limbal stem cells. Vigorous attempts are being made to expand limbal stem cells in culture to preserve or even enrich the stem cell population. Ex vivo expanded limbal stem cell treatment in limbal stem cell deficiency was first reported in 1997. In the 20 years since, various protocols have been developed for the cultivation of limbal epithelial cells. It is still not clear which method promotes effective stem cell viability and this remains a subject of ongoing research. The most preferred technique for limbal cell culture is the explant culture model. In this approach, a small donor eye limbal biopsy is placed as an explant onto a biocompatible substrate (preferably human amniotic membrane) for expansion. The outgrowth (cultivated limbal epithelial cells) is then surgically transferred to the recipient eye. Due to changing regulations concerning cell-based therapy, the implementation of cultivated limbal epithelial transplantation in accordance with Good Laboratory Practice using xenobiotic-free systems is becoming widely accepted both in Turkey and worldwide.

Detection of Toxolasma gondii in captive wild felids.

PubMed

Buddhirongawatr, Ruangrat; Tungsudjai, Siriporn; Chaichoune, Kridsada; Sangloung, Charoonluk; Tantawiwattananon, Nitipan; Phonaknguen, Rassameepen; Sukthana, Yaowalark

2006-01-01

Toxoplasma gondii can infect all species of warm-blooded animals, including humans, and causes serious diseases in immunocompromized hosts. Live tachyzoites derived from serial passage in HeLa culture were used in the Sabin-Feldman dye test for detection of Toxoplasma gondii antibody in serum samples of 21 captive wild felids including one fishing cat (Prion nailurus viverrina), one leopard (Panthera pardus), two flat-headed cats (Prion nailurus planiceps), 6 tigers (Panthera tigris), two leopard cats (Felis bengalensis), two clouded leopards (Felis nebulosa), 3 pumas (Puma concolor), and 4 jungle cats (Felis chaus). Antibodies to Toxoplasma gondii were founded in 9 of 21 felids (42.8%). This study revealed that cell culture-derived tachyzoites can be used successfully as a source of live organisms in a gold standard Sabin-Feldman dye test, which is simpler, cheaper and less ethically sensitive than in vivo inoculation.

Ligophorus pilengas n. sp. (Monogenea: Ancyrocephalidae) from the introduced So-iuy mullet, Mugil soiuy (Teleostei: Mugilidae), in the Sea of Azov and the Black Sea.

PubMed

Sarabeev, Volodimir Leonidovich; Balbuena, Juan Antonio

2004-04-01

The monogenean Ligophorus chabaudi was originally described on the gills of the flathead mullet, Mugil cephalus, and was subsequently reported on the So-iuy mullet, Mugil soiuy. However, the morphology of sclerotized parts and multivariate statistical analyses suggest that the form from the So-iuy mullet represents a new species. This study provides a description of the new species Ligophorus pilengas n. sp. and provides additional morphological data concerning the morphology of the ventral bar that might be useful for the diagnosis of Ligophorus. Ligophorus pilengas n. sp. is the second species of Ligophorus reported on the So-iuy mullet. Zoogeographical records indicate that L. pilengas n. sp. was probably introduced to the Black Sea and the Sea of Azov from the western Pacific Ocean together with its host.

Heavy metals in Mugil cephalus (Mugilidae) from the Ligurian Sea (North-West Mediterranean, Italy).

PubMed

Squadrone, S; Prearo, M; Gavinelli, S; Pellegrino, M; Tarasco, R; Benedetto, A; Abete, M C

2013-01-01

Pb, Cd and Hg in muscles of flathead mullet (Mugil cephalus), collected from Bocca di Magra, La Spezia (Ligurian Sea, Mediterranean Sea, Italy), were determined using graphite furnace atomic absorption spectrometry after microwave digestion for Pb and Cd and direct mercury analyser for Hg. Average Pb concentrations varied in the range 0.20-0.24 mg/kg, whereas Cd and Hg levels were negligible. None of the tested 200 samples exceeded the European regulatory limits as set by EC 1881/2006 and 420/2011. Metal concentrations in fish muscles were assessed for human consumption according to provisional tolerable weekly intake. The estimated values of Pb, Cd and Hg in M. cephalus's edible parts in this study were below the values established by the Joint WHO/FAO Expert Committee on Food Additives. Therefore, it can be concluded that there is no health problem in human consumption.

Aquatic Nuisance Species Locator

EPA Pesticide Factsheets

Data in this map has been collected by the United States Geological Survey's Nonindigenous Aquatic Species program located in Gainesville, Florida (http://nas.er.usgs.gov/default.aspx). This dataset may have some inaccuracies and is only current to June 15, 2012. The species identified in this dataset are not inclusive of all aquatic nuisance species, but rather a subset identified to be at risk for transport by recreational activities such as boating and angling. Additionally, the locations where organisims have been identified are also not inclusive and should be treated as a guide. Organisms are limited to the following: American bullfrog, Asian clam, Asian shore crab, Asian tunicate, Australian spotted jellyfish, Chinese mitten crab, New Zealand mudsnail, Colonial sea squirt, Alewife, Bighead carp, Black carp, Flathead catfish, Grass carp, Green crab, Lionfish, Northern snakehead, Quagga mussel, Round Goby, Ruffe, Rusty crayfish, Sea lamprey, Silver carp, Spiny water flea, Veined rapa whelk, Zebra mussel

Unexpected embolization of Teflon pledget in the left main stem during: a Bentall operation.

PubMed

Rubino, Antonino S; Serraino, Giuseppe F; Marsico, Roberto; Renzulli, Attilio

2011-01-01

We report the case of an 83-year-old man in whom acute left ventricular failure with ventricular arrhythmic storm developed during a Bentall operation. During re-exploration of the annular and coronary ostial anastomoses, no abnormality was seen, and none of the common sequelae of aortic root replacement was evident. The application of retrograde cardioplegia yielded a Teflon pledget that had migrated into the distal part of the left main stem. The pledget was removed, the anastomoses were reestablished, and the patient recovered uneventfully. This case suggests that left ostial anastomosis re-exploration should be carefully considered when no other cause of coronary insufficiency is obvious, and that retrograde cardioplegia may be useful to detect embolization in the left coronary system.

Unexpected Embolization of Teflon Pledget in the Left Main Stem during a Bentall Operation

PubMed Central

Rubino, Antonino S.; Serraino, Giuseppe F.; Marsico, Roberto; Renzulli, Attilio

2011-01-01

We report the case of an 83-year-old man in whom acute left ventricular failure with ventricular arrhythmic storm developed during a Bentall operation. During re-exploration of the annular and coronary ostial anastomoses, no abnormality was seen, and none of the common sequelae of aortic root replacement was evident. The application of retrograde cardioplegia yielded a Teflon pledget that had migrated into the distal part of the left main stem. The pledget was removed, the anastomoses were reestablished, and the patient recovered uneventfully. This case suggests that left ostial anastomosis re-exploration should be carefully considered when no other cause of coronary insufficiency is obvious, and that retrograde cardioplegia may be useful to detect embolization in the left coronary system. PMID:22163143

Stem cell mobilization and collection from pediatric patients and healthy children.

PubMed

Karakukcu, Musa; Unal, Ekrem

2015-08-01

Today, hematopoietic stem cell transplantation (HSCT) is a standard treatment for a variety of conditions in children, including certain malignancies, hemoglobinopathies, bone marrow failure syndromes, immunodeficiency and inborn metabolic disease. Two fundamentally different types of HSCT are categorized by the source of the stem cells. The first, autologous HSCT represents infusion of patient's own hematopoietic stem cells (HSCs) obtained from the patient; the second, allogeneic HSCT refers to the infusion of HSCs obtained from a donor via bone marrow harvest or apheresis. Bone marrow has been the typical source for HSCs for pediatric donors. Bone marrow harvest is a safe procedure mainly related to mild and transient side effects. Recently, a dramatically increased use of mobilized peripheral blood stem cells (PBSCs) in the autologous as well as allogeneic setting has been seen worldwide. There are limited data comparing mobilization regimens; also mobilization practices vary widely in children. The most commonly used approach includes granulocyte colony stimulating factor (G-CSF) at 10 mg/kg/day as a single daily dose for 4 days before the day of leukapheresis. G-CSF induced pain was less reported in children compared to adult donors. For the collection, there are several technical problems, derived from the size of the patient or donor, which must be considered before and during the apheresis. Vascular access, extracorporeal circuit volume, blood flow rates are the main limiting factors for PBSC collection in small children. Most children younger than 12 years require central vascular access for apheresis; line placement may require either general anesthesia or conscious sedation and many of the complications arise from the central venous catheter. In this review, we discuss that the ethical considerations and some principals regarding children serving as stem cell donors and the commonest sources of HSCs are presented in children, together with a discussion of how to collect and process these cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

Geomorphic responses of Duluth-area streams to the June 2012 flood, Minnesota

USGS Publications Warehouse

Fitzpatrick, Faith A.; Ellison, Christopher A.; Czuba, Christiana R.; Young, Benjamin M.; McCool, Molly M.; Groten, Joel T.

2016-09-01

In 2013, the U.S. Geological Survey, in cooperation with the Minnesota Pollution Control Agency, completed a geomorphic assessment of 51 Duluth-area stream sites in 20 basins to describe and document the stream geomorphic changes associated with the June 2012 flood. Heavy rainfall caused flood peaks with annual exceedance probabilities of less than 0.002 (flood recurrence interval of greater than 500 years) on large and small streams in and surrounding the Duluth area. A geomorphic segment-scale classification previously developed in 2003–4 by the U.S. Geological Survey for Duluth-area streams was used as a framework to characterize the observed flood-related responses along a longitudinal continuum from headwaters to rivermouths at Lake Superior related to drainage network position, slope, geologic setting, and valley type. Field assessments in 2013 followed and expanded on techniques used in 2003–4 at intensive and rapid sites. A third level of assessment was added in 2013 to increase the amount of quantitative data at a subset of 2003–4 rapid sites. Characteristics of channel morphology, channel bed substrate, exposed bars and soft sediment deposition, large wood, pools, and bank erosion were measured; and repeat photographs were taken. Additional measurements in 2013 included identification of Rosgen Level II stream types. The comparative analyses of field data collected in 2003–4 and again in 2013 indicated notable geomorphic changes, some of them expected and others not. As expected, in headwaters with gently sloping wetland segments, geomorphic changes were negligible (little measured or observed change). Downstream, middle main stems generally had bank and bluff erosion and bar formation as expected. Steep bedrock sites along middle and lower main stems had localized bank and bluff erosion in short sections with intermittent bedrock. Lower main stem and alluvial sites had bank erosion, widening, gravel bar deposition, and aggradation. Bar formation and accumulation of gravel was more widespread than expected among all main stems, especially for sites upstream and downstream from channel constrictions from road crossings, or even steep sites with localized, more gently sloping sections. Decreases in large wood and pools also were observed throughout the longitudinal continuum of main-stem sites, with immediate implications for fish and benthic invertebrate aquatic habitat. Whether or not the geomorphic conditions will return to their preflood condition depends on the location along the longitudinal continuum. The amount of large wood and pools may return after more moderate floods, whereas bars with coarse material may remain in place, locally altering flow direction and causing continued bank erosion. Results from this study can be used by local managers in postflood reconstruction efforts and provide baseline information for continued monitoring of geomorphic responses to the June 2012 flood.

Distinguishing the Biomass Allocation Variance Resulting from Ontogenetic Drift or Acclimation to Soil Texture

PubMed Central

Xie, Jiangbo; Tang, Lisong; Wang, Zhongyuan; Xu, Guiqing; Li, Yan

2012-01-01

In resource-poor environments, adjustment in plant biomass allocation implies a complex interplay between environmental signals and plant development rather than a delay in plant development alone. To understand how environmental factors influence biomass allocation or the developing phenotype, it is necessary to distinguish the biomass allocations resulting from environmental gradients or ontogenetic drift. Here, we compared the development trajectories of cotton plants (Gossypium herbaceum L.), which were grown in two contrasting soil textures during a 60-d period. Those results distinguished the biomass allocation pattern resulting from ontogenetic drift and the response to soil texture. The soil texture significantly changed the biomass allocation to leaves and roots, but not to stems. Soil texture also significantly changed the development trajectories of leaf and root traits, but did not change the scaling relationship between basal stem diameter and plant height. Results of nested ANOVAs of consecutive plant-size categories in both soil textures showed that soil gradients explained an average of 63.64–70.49% of the variation of biomass allocation to leaves and roots. Ontogenetic drift explained 77.47% of the variation in biomass allocation to stems. The results suggested that the environmental factors governed the biomass allocation to roots and leaves, and ontogenetic drift governed the biomass allocation to stems. The results demonstrated that biomass allocation to metabolically active organs (e.g., roots and leaves) was mainly governed by environmental factors, and that biomass allocation to metabolically non-active organs (e.g., stems) was mainly governed by ontogenetic drift. We concluded that differentiating the causes of development trajectories of plant traits was important to the understanding of plant response to environmental gradients. PMID:22911802

A prospective dual-energy X-ray absorptiometry study of bone remodeling after implantation of the Nanos short-stemmed prosthesis.

PubMed

Zeh, Alexander; Pankow, Franziska; Röllinhoff, Marc; Delank, Stefan; Wohlrab, David

2013-04-01

The aim of this study was to analyze the bone remodeling around the Nanos stem (Smith & Nephew, Marl, Germany) after primary total hip arthroplasty for coxarthrosis. In 25 patients (15 male, 10 female, mean age 59.9 years) with the diagnosis of coxarthrosis, a DEXA scan was performed immediately after surgery, 97 days (SD 6.1 days) and 368 days (SD 6.2 days) after implantation of a Nanos prosthesis. Plain radiographs were analyzed digitally for radiolucent lines, varus-valgus femoral stem alignment, measurement of stem migration and changes in varus-valgus femoral stem alignment. The position of the center of rotation (COR) and the offset were assessed pre- and postoperatively. Harris Hip Score was used to evaluate the clinical outcome. The DEXA scan showed a significant and relevant increase in BMD (Bone Mineral Density) in Gruen-Zone 6 (12%) and a decrease in Zone 1 (15%), 2 (5%) and 7 (12%), which was interpreted as reflecting a distal load transfer in the metaphysis of the femur. There was no clinically relevant migration or tilting of the Nanos stem. Radiolucent lines were noted in 12 cases, mainly at the polished tip area of the prosthesis; this was not regarded as a sign of impaired osseointegration. There was no significant difference between the position of the COR and the pre- and postoperative offset. The absence of stem migration, angulation, or relevant radiolucent lines is seen as evidence for an unimpaired osseointegration of the Nanos stem approximately 12 months after implantation. It is concluded that the Nanos prosthesis can reduce loss of BMD of the proximal femur composed with conventional stems or other short-stemmed implants.

Antitumor Activity of Rat Mesenchymal Stem Cells during Direct or Indirect Co-Culturing with C6 Glioma Cells.

PubMed

Gabashvili, A N; Baklaushev, V P; Grinenko, N F; Mel'nikov, P A; Cherepanov, S A; Levinsky, A B; Chehonin, V P

2016-02-01

The tumor-suppressive effect of rat mesenchymal stem cells against low-differentiated rat C6 glioma cells during their direct and indirect co-culturing and during culturing of C6 glioma cells in the medium conditioned by mesenchymal stem cells was studied in an in vitro experiment. The most pronounced antitumor activity of mesenchymal stem cells was observed during direct co-culturing with C6 glioma cells. The number of live C6 glioma cells during indirect co-culturing and during culturing in conditioned medium was slightly higher than during direct co-culturing, but significantly differed from the control (C6 glioma cells cultured in medium conditioned by C6 glioma cells). The cytotoxic effect of medium conditioned by mesenchymal stem cells was not related to medium depletion by glioma cells during their growth. The medium conditioned by other "non-stem" cells (rat astrocytes and fibroblasts) produced no tumor-suppressive effect. Rat mesenchymal stem cells, similar to rat C6 glioma cells express connexin 43, the main astroglial gap junction protein. During co-culturing, mesenchymal stem cells and glioma C6 cells formed functionally active gap junctions. Gap junction blockade with connexon inhibitor carbenoxolone attenuated the antitumor effect observed during direct co-culturing of C6 glioma cells and mesenchymal stem cells to the level produced by conditioned medium. Cell-cell signaling mediated by gap junctions can be a mechanism of the tumor-suppressive effect of mesenchymal stem cells against C6 glioma cells. This phenomenon can be used for the development of new methods of cell therapy for high-grade malignant gliomas.

The use of stem cells in regenerative medicine for Parkinson's and Huntington's Diseases.

PubMed

Lescaudron, L; Naveilhan, P; Neveu, I

2012-01-01

Cell transplantation has been proposed as a means of replacing specific cell populations lost through neurodegenerative processes such as that seen in Parkinson's or Huntington's diseases. Improvement of the clinical symptoms has been observed in a number of Parkinson and Huntington's patients transplanted with freshly isolated fetal brain tissue but such restorative approach is greatly hampered by logistic and ethical concerns relative to the use of fetal tissue, in addition to potential side effects that remain to be controlled. In this context, stem cells that are capable of self-renewal and can differentiate into neurons, have received a great deal of interest, as demonstrated by the numerous studies based on the transplantation of neural stem/progenitor cells, embryonic stem cells or mesenchymal stem cells into animal models of Parkinson's or Huntington's diseases. More recently, the induction of pluripotent stem cells from somatic adult cells has raised a new hope for the treatment of neurodegenerative diseases. In the present article, we review the main experimental approaches to assess the efficiency of cell-based therapy for Parkinson's or Huntington's diseases, and discuss the recent advances in using stem cells to replace lost dopaminergic mesencephalic or striatal neurons. Characteristics of the different stem cells are extensively examined with a special attention to their ability of producing neurotrophic or immunosuppressive factors, as these may provide a favourable environment for brain tissue repair and long-term survival of transplanted cells in the central nervous system. Thus, stem cell therapy can be a valuable tool in regenerative medicine.

Separation technologies for stem cell bioprocessing.

PubMed

Diogo, Maria Margarida; da Silva, Cláudia Lobato; Cabral, Joaquim M S

2012-11-01

Stem cells have been the focus of an intense research due to their potential in Regenerative Medicine, drug discovery, toxicology studies, as well as for fundamental studies on developmental biology and human disease mechanisms. To fully accomplish this potential, the successful application of separation processes for the isolation and purification of stem cells and stem cell-derived cells is a crucial issue. Although separation methods have been used over the past decades for the isolation and enrichment of hematopoietic stem/progenitor cells for transplantation in hemato-oncological settings, recent achievements in the stem cell field have created new challenges including the need for novel scalable separation processes with a higher resolution and more cost-effective. Important examples are the need for high-resolution methods for the separation of heterogeneous populations of multipotent adult stem cells to study their differential biological features and clinical utility, as well as for the depletion of tumorigenic cells after pluripotent stem cell differentiation. Focusing on these challenges, this review presents a critical assessment of separation processes that have been used in the stem cell field, as well as their current and potential applications. The techniques are grouped according to the fundamental principles that govern cell separation, which are defined by the main physical, biophysical, and affinity properties of cells. A special emphasis is given to novel and promising approaches such as affinity-based methods that take advantage of the use of new ligands (e.g., aptamers, lectins), as well as to novel biophysical-based methods requiring no cell labeling and integrated with microscale technologies. Copyright © 2012 Wiley Periodicals, Inc.

Responsible Translation of Stem Cell Research: An Assessment of Clinical Trial Registration and Publications.

PubMed

Fung, Moses; Yuan, Yan; Atkins, Harold; Shi, Qian; Bubela, Tania

2017-05-09

We assessed the extent to which the publication of clinical trial results of innovative cell-based interventions reflects International Society for Stem Cell Research best practice guidelines. We assessed: (1) characteristics and time to publication of completed trials; (2) quality of reported trials; and (3) results of published trials. We identified and analyzed publications from 1,052 novel stem cell clinical trials: 179 (45.4%) of 393 completed trials had published results; 48 trials were registered by known stem cell tourism clinics, none of which reported results. Completed non-industry-sponsored trials initially published more rapidly, but differences with industry-sponsored trials decreased over time. Most publications reported safety, and 67.3% (mainly early-stage trials) reported positive outcomes. A higher proportion of industry trials reported positive efficacy. Heightened patient expectations for stem cell therapies give rise to ethical obligations for the transparent conduct of clinical trials. Reporting guidelines need to be developed that are specific to early-phase clinical trials. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Genetically Encoded Photoactuators and Photosensors for Characterization and Manipulation of Pluripotent Stem Cells

PubMed Central

Pomeroy, Jordan E.; Nguyen, Hung X.; Hoffman, Brenton D.; Bursac, Nenad

2017-01-01

Our knowledge of pluripotent stem cell biology has advanced considerably in the past four decades, but it has yet to deliver on the great promise of regenerative medicine. The slow progress can be mainly attributed to our incomplete understanding of the complex biologic processes regulating the dynamic developmental pathways from pluripotency to fully-differentiated states of functional somatic cells. Much of the difficulty arises from our lack of specific tools to query, or manipulate, the molecular scale circuitry on both single-cell and organismal levels. Fortunately, the last two decades of progress in the field of optogenetics have produced a variety of genetically encoded, light-mediated tools that enable visualization and control of the spatiotemporal regulation of cellular function. The merging of optogenetics and pluripotent stem cell biology could thus be an important step toward realization of the clinical potential of pluripotent stem cells. In this review, we have surveyed available genetically encoded photoactuators and photosensors, a rapidly expanding toolbox, with particular attention to those with utility for studying pluripotent stem cells. PMID:28912894

In Vitro Generation of Vascular Wall-Resident Multipotent Stem Cells of Mesenchymal Nature from Murine Induced Pluripotent Stem Cells.

PubMed

Steens, Jennifer; Zuk, Melanie; Benchellal, Mohamed; Bornemann, Lea; Teichweyde, Nadine; Hess, Julia; Unger, Kristian; Görgens, André; Klump, Hannes; Klein, Diana

2017-04-11

The vascular wall (VW) serves as a niche for mesenchymal stem cells (MSCs). In general, tissue-specific stem cells differentiate mainly to the tissue type from which they derive, indicating that there is a certain code or priming within the cells as determined by the tissue of origin. Here we report the in vitro generation of VW-typical MSCs from induced pluripotent stem cells (iPSCs), based on a VW-MSC-specific gene code. Using a lentiviral vector expressing the so-called Yamanaka factors, we reprogrammed tail dermal fibroblasts from transgenic mice containing the GFP gene integrated into the Nestin-locus (NEST-iPSCs) to facilitate lineage tracing after subsequent MSC differentiation. A lentiviral vector expressing a small set of recently identified human VW-MSC-specific HOX genes then induced MSC differentiation. This direct programming approach successfully mediated the generation of VW-typical MSCs with classical MSC characteristics, both in vitro and in vivo. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Optimization of a serum-free culture medium for mouse embryonic stem cells using design of experiments (DoE) methodology.

PubMed

Knöspel, Fanny; Schindler, Rudolf K; Lübberstedt, Marc; Petzolt, Stephanie; Gerlach, Jörg C; Zeilinger, Katrin

2010-12-01

The in vitro culture behaviour of embryonic stem cells (ESC) is strongly influenced by the culture conditions. Current culture media for expansion of ESC contain some undefined substances. Considering potential clinical translation work with such cells, the use of defined media is desirable. We have used Design of Experiments (DoE) methods to investigate the composition of a serum-free chemically defined culture medium for expansion of mouse embryonic stem cells (mESC). Factor screening analysis according to Plackett-Burman revealed that insulin and leukaemia inhibitory factor (LIF) had a significant positive influence on the proliferation activity of the cells, while zinc and L: -cysteine reduced the cell growth. Further analysis using minimum run resolution IV (MinRes IV) design indicates that following factor adjustment LIF becomes the main factor for the survival and proliferation of mESC. In conclusion, DoE screening assays are applicable to develop and to refine culture media for stem cells and could also be employed to optimize culture media for human embryonic stem cells (hESC).

Requirement of myomaker-mediated stem cell fusion for skeletal muscle hypertrophy

PubMed Central

Goh, Qingnian; Millay, Douglas P

2017-01-01

Fusion of skeletal muscle stem/progenitor cells is required for proper development and regeneration, however the significance of this process during adult muscle hypertrophy has not been explored. In response to muscle overload after synergist ablation in mice, we show that myomaker, a muscle specific membrane protein essential for myoblast fusion, is activated mainly in muscle progenitors and not myofibers. We rendered muscle progenitors fusion-incompetent through genetic deletion of myomaker in muscle stem cells and observed a complete reduction of overload-induced hypertrophy. This blunted hypertrophic response was associated with a reduction in Akt and p70s6k signaling and protein synthesis, suggesting a link between myonuclear accretion and activation of pro-hypertrophic pathways. Furthermore, fusion-incompetent muscle exhibited increased fibrosis after muscle overload, indicating a protective role for normal stem cell activity in reducing myofiber strain associated with hypertrophy. These findings reveal an essential contribution of myomaker-mediated stem cell fusion during physiological adult muscle hypertrophy. DOI: http://dx.doi.org/10.7554/eLife.20007.001 PMID:28186492

Biomechanical study of the tibia in knee replacement revision.

PubMed

Quílez, M P; Pérez, M A; Seral-García, B

2015-01-01

The best management of severe bone defects following total knee replacement is still controversial. Metal augments, tantalum cones and porous tibial sleeves could help the surgeon to manage any type of bone loss, providing a stable and durable knee joint reconstruction. Five different types of prostheses have been analysed: one prosthesis with straight stem; two prostheses with offset stem, with and without supplement, and two prostheses with sleeves, with and without stem. The purpose of this study is to report a finite element study of revision knee tibial implants. The main objective was to analyse the tibial bone density changes and Von Misses tension changes following different tibial implant designs. In all cases, the bone density decreases in the proximal epiphysis and medullary channels, with a bone density increase also being predicted in the diaphysis and at the bone around the stems tips. The highest value of Von Misses stress has been obtained for the straight tibial stem, and the lowest for the stemless metaphyseal sleeves prosthesis. Copyright © 2014 SECOT. Published by Elsevier Espana. All rights reserved.

Functional significance of CD105-positive cells in papillary renal cell carcinoma.

PubMed

Matak, Damian; Brodaczewska, Klaudia K; Szczylik, Cezary; Koch, Irena; Myszczyszyn, Adam; Lipiec, Monika; Lewicki, Slawomir; Szymanski, Lukasz; Zdanowski, Robert; Czarnecka, Anna M

2017-01-05

CD105 was postulated as a renal cell carcinoma (RCC) stem cell marker, and CD133 as a putative RCC progenitor. Hypoxia, a natural microenvironment that prevails in tumors, was also incorporated into the study, especially in terms of the promotion of hypothetical stem-like cell properties. Within this study, we verify the existence of CD105+ and CD133+ populations in selected papillary subtype RCC (pRCC) cell lines. Both populations were analyzed for correlation with stem-like cell properties, such as stemness gene expression, and sphere and colony formation. For the preliminary analysis, several RCC cell lines were chosen (786-O, SMKT-R2, Caki-2, 796-P, ACHN, RCC6) and the control was human kidney cancer stem cells (HKCSC) and renal cells of embryonic origin (ASE-5063). Four cell lines were chosen for further investigation: Caki-2 (one of the highest numbers of CD105+ cells; primary origin), ACHN (a low number of CD105+ cells; metastatic origin), HKCSC (putative positive control), and ASE-5063 (additional control). In 769-P and RCC6, we could not detect a CD105+ population. Hypoxia variously affects pRCC cell growth, and mainly diminishes the stem-like properties of cells. Furthermore, we could not observe the correlation of CD105 and/or CD133 expression with the enhancement of stem-like properties. Based on this analysis, CD105/CD133 cannot be validated as cancer stem cell markers of pRCC cell lines.

Human Embryonic Stem Cell Therapy in Crohn’s Disease: A Case Report

PubMed Central

Shroff, Geeta

2016-01-01

Patient: Male, 21 Final Diagnosis: Crohn’s disease Symptoms: Intolerance to specific foods • abdominal pain and diarrhea Medication: Human embryonic stem cell therapy Clinical Procedure: Human embryonic stem cell transplantation Specialty: Gastroenterology Objective: Unusual or unexpected effect of treatment Background: Crohn’s disease is a chronic inflammatory disease of the intestines, mainly the colon and ileum, related with ulcers and fistulae. It is estimated to affect 565 000 people in the United States. Currently available therapies, such as antibiotics, thiopurines, and anti-tumor necrosis factor-alpha agents, are only observed to reduce the complications associated with Crohn’s disease and to improve quality of life, but cannot cure the disease. Stem cell therapy appears to have certain advantages over conventional therapies. Our study aimed to evaluate the efficacy of human embryonic stem cell therapy in a patient with Crohn’s disease. Case Report: A 21-year-old male with chief complaints of intolerance to specific foods, abdominal pain, and diarrhea underwent human embryonic stem cell therapy for two months. After undergoing human embryonic stem cell therapy, the patient showed symptomatic relief. He had no complaints of back pain, abdominal pain, or diarrhea and had improved digestion. The patient had no signs and symptoms of skin infection, and had improved limb stamina, strength, and endurance. The condition of patient was stable after the therapy. Conclusions: Human embryonic stem cell therapy might serve as a new optimistic treatment approach for Crohn’s disease. PMID:26923312

Future research and therapeutic applications of human stem cells: general, regulatory, and bioethical aspects.

PubMed

Liras, Antonio

2010-12-10

There is much to be investigated about the specific characteristics of stem cells and about the efficacy and safety of the new drugs based on this type of cells, both embryonic as adult stem cells, for several therapeutic indications (cardiovascular and ischemic diseases, diabetes, hematopoietic diseases, liver diseases). Along with recent progress in transference of nuclei from human somatic cells, as well as iPSC technology, has allowed availability of lineages of all three germ layers genetically identical to those of the donor patient, which permits safe transplantation of organ-tissue-specific adult stem cells with no immune rejection. The main objective is the need for expansion of stem cell characteristics to maximize stem cell efficacy (i.e. the proper selection of a stem cell) and the efficacy (maximum effect) and safety of stem cell derived drugs. Other considerations to take into account in cell therapy will be the suitability of infrastructure and technical staff, biomaterials, production costs, biobanks, biosecurity, and the biotechnological industry. The general objectives in the area of stem cell research in the next few years, are related to identification of therapeutic targets and potential therapeutic tests, studies of cell differentiation and physiological mechanisms, culture conditions of pluripotent stem cells and efficacy and safety tests for stem cell-based drugs or procedures to be performed in both animal and human models in the corresponding clinical trials. A regulatory framework will be required to ensure patient accessibility to products and governmental assistance for their regulation and control. Bioethical aspects will be required related to the scientific and therapeutic relevance and cost of cryopreservation over time, but specially with respect to embryos which may ultimately be used for scientific uses of research as source of embryonic stem cells, in which case the bioethical conflict may be further aggravated.

Mercury Contributions from Flint Creek and other Tributaries to the Upper Clark Fork River in Northwestern Montana

NASA Astrophysics Data System (ADS)

Langner, H.; Young, M.; Staats, M. F.

2013-12-01

Methylmercury contamination in biota is a major factor diminishing the environmental quality of the Upper Clark Fork River (CFR), e.g. by triggering human consumption limits of fish. The CFR is subject to one of the largest Superfund cleanup projects in the US, but remediation and restoration is currently focused exclusively on other mining-related contaminants (As, Cu, Zn, Pb, Cd), which may be counterproductive with respect to the bio-availability of mercury, for example by creation of wetlands along mercury-contaminated reaches of the river. The identification and elimination of Hg sources is an essential step toward reducing the methylmercury exposure in the biota of the CFR watershed because a strong correlation exists between total mercury levels in river sediment and methylmercury levels in aquatic life. We analyzed duplicate samples from the top sediment layer of the main stem and significant tributaries to the Clark Fork River along a 240 km reach between Butte, MT and downstream of the Missoula Valley. Mercury concentrations were 1.3 × 1.6 (mean × SD, n = 35) in the main stem. Concentrations in tributaries varied widely (0.02 to 85 mg/kg) and seemed only loosely related to the number of historic precious metal mines in the watershed. In the upper reach of the CFR, elevated Hg levels are likely caused by residual contaminated sediments in the flood plain. Levels tend to decrease downstream until Drummond, MT, where Flint Creek contributes a significant amount of mercury, causing Hg levels in the main stem CFR to increase from 0.7 to 4 mg/kg. Levels continue to decrease downstream. Flint Creek is the single largest contributor of Hg to the CFR. Detailed sampling of the main stem Flint Creek and tributaries (26 sites) showed extremely high levels in two tributaries (22 to 85 mg/kg) where historic milling operations were located. Elimination of these point sources may be accomplished comparatively economically and may significantly reduce mercury levels in Flint Creek and the Clark Fork River basin.

Density-Dependent Regulation of Brook Trout Population Dynamics along a Core-Periphery Distribution Gradient in a Central Appalachian Watershed

PubMed Central

Huntsman, Brock M.; Petty, J. Todd

2014-01-01

Spatial population models predict strong density-dependence and relatively stable population dynamics near the core of a species' distribution with increasing variance and importance of density-independent processes operating towards the population periphery. Using a 10-year data set and an information-theoretic approach, we tested a series of candidate models considering density-dependent and density-independent controls on brook trout population dynamics across a core-periphery distribution gradient within a central Appalachian watershed. We sampled seven sub-populations with study sites ranging in drainage area from 1.3–60 km2 and long-term average densities ranging from 0.335–0.006 trout/m. Modeled response variables included per capita population growth rate of young-of-the-year, adult, and total brook trout. We also quantified a stock-recruitment relationship for the headwater population and coefficients of variability in mean trout density for all sub-populations over time. Density-dependent regulation was prevalent throughout the study area regardless of stream size. However, density-independent temperature models carried substantial weight and likely reflect the effect of year-to-year variability in water temperature on trout dispersal between cold tributaries and warm main stems. Estimated adult carrying capacities decreased exponentially with increasing stream size from 0.24 trout/m in headwaters to 0.005 trout/m in the main stem. Finally, temporal variance in brook trout population size was lowest in the high-density headwater population, tended to peak in mid-sized streams and declined slightly in the largest streams with the lowest densities. Our results provide support for the hypothesis that local density-dependent processes have a strong control on brook trout dynamics across the entire distribution gradient. However, the mechanisms of regulation likely shift from competition for limited food and space in headwater streams to competition for thermal refugia in larger main stems. It also is likely that source-sink dynamics and dispersal from small headwater habitats may partially influence brook trout population dynamics in the main stem. PMID:24618602

Channel Width Change as a Potential Sediment Source, Minnesota River Basin

NASA Astrophysics Data System (ADS)

Lauer, J. W.; Echterling, C.; Lenhart, C. F.; Rausch, R.; Belmont, P.

2017-12-01

Turbidity and suspended sediment are important management considerations along the Minnesota River. The system has experience large and relatively consistent increases in both discharge and channel width over the past century. Here we consider the potential role of channel cross section enlargement as a sediment source. Reach-average channel width was digitized from aerial images dated between 1937 and 2015 along multiple sub-reaches of the Minnesota River and its major tributaries. Many of the sub-reaches include several actively migrating bends. The analysis shows relatively consistent increases in width over time, with average increase rates of 0.4 percent per year. Extrapolation to the river network using a regional relationship for cross-sectional area vs. drainage area indicates that large tributaries and main-stem reaches account for most of the bankfull cross-sectional volume in the basin. Larger tributaries and the main stem thus appear more important for widening related sediment production than small tributaries. On a basin-wide basis, widening could be responsible for a gross supply of more sediment than has been gaged at several main-stem sites, indicating that there may be important sinks for both sand and silt/clay size material distributed throughout the system. Sediment storage is probably largest along the lowest-slope reaches of the main stem. While channel width appears to have adjusted relatively quickly in response to discharge and other hydraulic modifications, net storage of sediment in floodplains probably occurs sufficiently slowly that depth adjustment will lag width adjustment significantly. Detailed analysis of the lower Minnesota River using a river segmenting approach allows for a more detailed assessment of reach-scale processes. Away from channel cutoffs, elongation of the channel at eroding bends is consistent with rates observed on other actively migrating rivers. However, the sinuosity increase has been more than compensated by several natural and engineered cutoffs. The sinuosity change away from cutoffs probably plays a relatively modest role in the reach's sediment budget. However, point bars and abandoned oxbow lakes are important zones of sediment storage that may be large enough to account for much of the widening-related production of sand in the reach.

Brachypodium as an experimental system for the study of stem parenchyma biology in grasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jensen, Jacob Kruger; Wilkerson, Curtis Gene; Ma, Wujun

Stem parenchyma is a major cell type that serves key metabolic functions for the plant especially in large grasses, such as sugarcane and sweet sorghum, where it serves to store sucrose or other products of photosynthesis. It is therefore desirable to understand the metabolism of this cell type as well as the mechanisms by which it provides its function for the rest of the plant. Ultimately, this information can be used to selectively manipulate this cell type in a controlled manner to achieve crop improvement. In this study, we show that Brachypodium distachyon is a useful model system for stemmore » pith parenchyma biology. Brachypodium can be grown under condition where it resembles the growth patterns of important crops in that it produces large amounts of stem material with the lower leaves senescing and with significant stores of photosynthate located in the stem parenchyma cell types. We further characterize stem plastid morphology as a function of tissue types, as this organelle is central for a number of metabolic pathways, and quantify gene expression for the four main classes of starch biosynthetic genes. Notably, we find several of these genes differentially regulated between stem and leaf. Furthermore, these studies show, consistent with other grasses, that the stem functions as a specialized storage compartment in Brachypodium.« less

Modelling reveals endogenous osmotic adaptation of storage tissue water potential as an important driver determining different stem diameter variation patterns in the mangrove species Avicennia marina and Rhizophora stylosa.

PubMed

Vandegehuchte, Maurits W; Guyot, Adrien; Hubeau, Michiel; De Swaef, Tom; Lockington, David A; Steppe, Kathy

2014-09-01

Stem diameter variations are mainly determined by the radial water transport between xylem and storage tissues. This radial transport results from the water potential difference between these tissues, which is influenced by both hydraulic and carbon related processes. Measurements have shown that when subjected to the same environmental conditions, the co-occurring mangrove species Avicennia marina and Rhizophora stylosa unexpectedly show a totally different pattern in daily stem diameter variation. Using in situ measurements of stem diameter variation, stem water potential and sap flow, a mechanistic flow and storage model based on the cohesion-tension theory was applied to assess the differences in osmotic storage water potential between Avicennia marina and Rhizophora stylosa. Both species, subjected to the same environmental conditions, showed a resembling daily pattern in simulated osmotic storage water potential. However, the osmotic storage water potential of R. stylosa started to decrease slightly after that of A. marina in the morning and increased again slightly later in the evening. This small shift in osmotic storage water potential likely underlaid the marked differences in daily stem diameter variation pattern between the two species. The results show that in addition to environmental dynamics, endogenous changes in the osmotic storage water potential must be taken into account in order to accurately predict stem diameter variations, and hence growth.

Stem cell research and policy in India: current scenario and future perspective.

PubMed

Sharma, Alka

2009-01-01

Stem cell research is an exciting area of biomedical research, with potential to advance cell biology, and other new modalities of treatment for many untreatable diseases. The potential resides in the ability of these cells to develop into many different cell types in the body. In India, efforts are being made on several fronts to promote this area in an integrated way. The main features of the strategy are: explore the full potential of adult and embryonic stem cells (ESCs) through basic and translational research; generate patient specific human ESC lines; enhance creation of animal models for pre-clinical studies; virtual network of Centres; creation institutions; generation of well trained manpower; build partnership with large companies in path-breaking areas; promote closer interactions amongst basic scientists, clinical researchers and the industry. Newer initiatives include: establishment of a dedicated institute for stem cell science and regenerative medicine with its translational units; GMP and clean room facilities in medical schools; creation of a system for multi-centric clinical studies using autologous adult stem cells; national and international training courses for providing training to the students and the young scientists in the both embryonic and adult stem cells; and formulation of guidelines to conduct stem cell research in a responsible and ethically sensitive manner in the country. The core capacity must be nurtured and built to create the required critical mass to have impact.

Brachypodium as an experimental system for the study of stem parenchyma biology in grasses

DOE PAGES

Jensen, Jacob Kruger; Wilkerson, Curtis Gene; Ma, Wujun

2017-03-01

Stem parenchyma is a major cell type that serves key metabolic functions for the plant especially in large grasses, such as sugarcane and sweet sorghum, where it serves to store sucrose or other products of photosynthesis. It is therefore desirable to understand the metabolism of this cell type as well as the mechanisms by which it provides its function for the rest of the plant. Ultimately, this information can be used to selectively manipulate this cell type in a controlled manner to achieve crop improvement. In this study, we show that Brachypodium distachyon is a useful model system for stemmore » pith parenchyma biology. Brachypodium can be grown under condition where it resembles the growth patterns of important crops in that it produces large amounts of stem material with the lower leaves senescing and with significant stores of photosynthate located in the stem parenchyma cell types. We further characterize stem plastid morphology as a function of tissue types, as this organelle is central for a number of metabolic pathways, and quantify gene expression for the four main classes of starch biosynthetic genes. Notably, we find several of these genes differentially regulated between stem and leaf. Furthermore, these studies show, consistent with other grasses, that the stem functions as a specialized storage compartment in Brachypodium.« less

Potential economic benefits of adapting agricultural production systems to future climate change

USGS Publications Warehouse

Fagre, Daniel B.; Pederson, Gregory; Bengtson, Lindsey E.; Prato, Tony; Qui, Zeyuan; Williams, Jimmie R.

2010-01-01

Potential economic impacts of future climate change on crop enterprise net returns and annual net farm income (NFI) are evaluated for small and large representative farms in Flathead Valley in Northwest Montana. Crop enterprise net returns and NFI in an historical climate period (1960–2005) and future climate period (2006–2050) are compared when agricultural production systems (APSs) are adapted to future climate change. Climate conditions in the future climate period are based on the A1B, B1, and A2 CO2 emission scenarios from the Intergovernmental Panel on Climate Change Fourth Assessment Report. Steps in the evaluation include: (1) specifying crop enterprises and APSs (i.e., combinations of crop enterprises) in consultation with locals producers; (2) simulating crop yields for two soils, crop prices, crop enterprises costs, and NFIs for APSs; (3) determining the dominant APS in the historical and future climate periods in terms of NFI; and (4) determining whether NFI for the dominant APS in the historical climate period is superior to NFI for the dominant APS in the future climate period. Crop yields are simulated using the Environmental/Policy Integrated Climate (EPIC) model and dominance comparisons for NFI are based on the stochastic efficiency with respect to a function (SERF) criterion. Probability distributions that best fit the EPIC-simulated crop yields are used to simulate 100 values for crop yields for the two soils in the historical and future climate periods. Best-fitting probability distributions for historical inflation-adjusted crop prices and specified triangular probability distributions for crop enterprise costs are used to simulate 100 values for crop prices and crop enterprise costs. Averaged over all crop enterprises, farm sizes, and soil types, simulated net return per ha averaged over all crop enterprises decreased 24% and simulated mean NFI for APSs decreased 57% between the historical and future climate periods. Although adapting APSs to future climate change is advantageous (i.e., NFI with adaptation is superior to NFI without adaptation based on SERF), in six of the nine cases in which adaptation is advantageous, NFI with adaptation in the future climate period is inferior to NFI in the historical climate period. Therefore, adaptation of APSs to future climate change in Flathead Valley is insufficient to offset the adverse impacts on NFI of such change.

Heavy metals in fish from the Aleutians: Interspecific and locational differences

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burger, Joanna, E-mail: burger@biology.rutgers.edu; Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, NJ; Consortium for Risk Evaluation with Stakeholder Participation, Vanderbilt University, Nashville, TN 37235

The objectives of this study were to examine levels of arsenic, cadmium, lead, mercury and selenium in edible tissue of seven species of marine fish collected from several Aleutian islands (in 2004) to determine: (1) interspecific differences, (2) locational differences (among Aleutian Islands), (3) size-related differences in any metal levels within a species, and (4) potential risk to the fish or to predators on the fish, including humans. We also compared metals levels to those of three other fish species previously examined in detail, as well as examining metals in the edible tissue of octopus (Octopus dofleini). Octopus did notmore » have the highest levels of any metal. There were significant interspecific differences in all metal levels among the fish species, although the differences were less than an order of magnitude, except for arsenic (mean of 19,500 ppb in Flathead sole, Hippoglossoides elassodon). Significant intraisland variation occurred among the four sites on Amchitka, but there was not a consistent pattern. There were significant interisland differences for some metals and species. Mercury levels increased significantly with size for several species; lead increased significantly for only one fish species; and cadmium and selenium decreased significantly with size for halibut (Hippoglossus stenolepis). The Alaskan Department of Health and Social Services supports unrestricted consumption of most Alaskan fish species for all people, including pregnant women. Most mean metal concentrations were well below the levels known to adversely affect the fish themselves, or predators that consume them (including humans), except for mercury in three fish species (mean levels just below 0.3 ppm), and arsenic in two fish species. However, even at low mercury levels, people who consume fish almost daily will exceed guideline values from the Centers for Disease Control and the Environmental Protection Agency. - Highlights: • Cadmium, lead, mercury and selenium levels differed among 10 fish species from the Aleutians. • Mean Arsenic was as high as 19,500 ppb (flathead sole, Hippoglossoides elassodon). • Mercury levels increased significantly with fish size for several species. • Metal levels were generally below adverse effects levels for fish and their predators. • Mercury and arsenic might pose a risk to human consumers, and require further examination.« less

Uniquely Acquired Vintage Seismic Reflection Data Reveal the Stratigraphic and Tectonic History of the Montana Disturbed Belt, USA

NASA Astrophysics Data System (ADS)

Speece, M. A.; Link, C. A.; Stickney, M.

2011-12-01

In 1983 and 1984 Techco of Denver, Colorado, acquired approximately 302 linear kilometers of two-dimensional (2D) seismic reflection data in Flathead and Lake Counties, Montana, USA, as part of an initiative to identify potential drilling targets beneath the Swan and Whitefish Mountain Ranges and adjacent basins of northwestern Montana. These seismic lines were collected in the Montana Disturbed Belt (MDB) or Montana thrust belt along the western edge of Glacier National Park in mountainous terrain with complicated subsurface structures including thrust faults and folds. These structures formed during the Laramide Orogeny as sedimentary rocks of the Precambrian Belt Supergroup were thrust eastward. Later, during the Cenozoic, high-angle normal faults produced prominent west-facing mountain scarps of the Mission, Swan and Whitefish mountains. The 1983 data set consisted of two profiles of 24-fold (96-channels) Vibroseis data and four profiles of 24-fold (96-channels) helicopter-assisted dynamite data. The dynamite data were collected using the Poulter Method in which explosives were placed on poles and air shots were recorded. The 1983 dynamite profiles extend from southwest to northeast across the Whitefish Mountain Range to the edge of Glacier National Park and the Vibroseis data were collected along nearby roadways. The 1984 data set consists of four profiles of 30-fold (120-channels) helicopter-assisted dynamite data that were also collected using the Poulter Method. The 1984 profiles cross the Swan Mountain Range between Flathead Lake and Glacier National Park. All of these data sets were recently donated to Montana Tech and subsequently recovered from nine-track tape. Conventionally processed seismic stacked sections from the 1980s of these data show evidence of a basement decollement that separates relatively undeformed basement from overlying structures of the MDB. Unfortunately, these data sets have not been processed using modern seismic processing techniques including linear noise suppression of the air wave and ground roll, refraction statics, and prestack migration. Reprocessing of these data using state-of-the-art seismic reflection processing techniques will provide a detailed picture of the stratigraphy and tectonic framework for this region. Moreover, extended correlations of the Vibroseis records to Moho depths might reveal new insights on crustal thickness and provide a framework for understanding crustal thickening during the Laramide Orogeny as well as later Cenozoic extension.

Tuning stochastic matrix models with hydrologic data to predict the population dynamics of a riverine fish

USGS Publications Warehouse

Sakaris, P.C.; Irwin, E.R.

2010-01-01

We developed stochastic matrix models to evaluate the effects of hydrologic alteration and variable mortality on the population dynamics of a lotie fish in a regulated river system. Models were applied to a representative lotic fish species, the flathead catfish (Pylodictis olivaris), for which two populations were examined: a native population from a regulated reach of the Coosa River (Alabama, USA) and an introduced population from an unregulated section of the Ocmulgee River (Georgia, USA). Size-classified matrix models were constructed for both populations, and residuals from catch-curve regressions were used as indices of year class strength (i.e., recruitment). A multiple regression model indicated that recruitment of flathead catfish in the Coosa River was positively related to the frequency of spring pulses between 283 and 566 m3/s. For the Ocmulgee River population, multiple regression models indicated that year class strength was negatively related to mean March discharge and positively related to June low flow. When the Coosa population was modeled to experience five consecutive years of favorable hydrologic conditions during a 50-year projection period, it exhibited a substantial spike in size and increased at an overall 0.2% annual rate. When modeled to experience five years of unfavorable hydrologic conditions, the Coosa population initially exhibited a decrease in size but later stabilized and increased at a 0.4% annual rate following the decline. When the Ocmulgee River population was modeled to experience five years of favorable conditions, it exhibited a substantial spike in size and increased at an overall 0.4% annual rate. After the Ocmulgee population experienced five years of unfavorable conditions, a sharp decline in population size was predicted. However, the population quickly recovered, with population size increasing at a 0.3% annual rate following the decline. In general, stochastic population growth in the Ocmulgee River was more erratic and variable than population growth in the Coosa River. We encourage ecologists to develop similar models for other lotic species, particularly in regulated river systems. Successful management of fish populations in regulated systems requires that we are able to predict how hydrology affects recruitment and will ultimately influence the population dynamics of fishes. ?? 2010 by the Ecological Society of America.

Potential economic benefits of adapting agricultural production systems to future climate change.

PubMed

Prato, Tony; Zeyuan, Qiu; Pederson, Gregory; Fagre, Dan; Bengtson, Lindsey E; Williams, Jimmy R

2010-03-01

Potential economic impacts of future climate change on crop enterprise net returns and annual net farm income (NFI) are evaluated for small and large representative farms in Flathead Valley in Northwest Montana. Crop enterprise net returns and NFI in an historical climate period (1960-2005) and future climate period (2006-2050) are compared when agricultural production systems (APSs) are adapted to future climate change. Climate conditions in the future climate period are based on the A1B, B1, and A2 CO(2) emission scenarios from the Intergovernmental Panel on Climate Change Fourth Assessment Report. Steps in the evaluation include: (1) specifying crop enterprises and APSs (i.e., combinations of crop enterprises) in consultation with locals producers; (2) simulating crop yields for two soils, crop prices, crop enterprises costs, and NFIs for APSs; (3) determining the dominant APS in the historical and future climate periods in terms of NFI; and (4) determining whether NFI for the dominant APS in the historical climate period is superior to NFI for the dominant APS in the future climate period. Crop yields are simulated using the Environmental/Policy Integrated Climate (EPIC) model and dominance comparisons for NFI are based on the stochastic efficiency with respect to a function (SERF) criterion. Probability distributions that best fit the EPIC-simulated crop yields are used to simulate 100 values for crop yields for the two soils in the historical and future climate periods. Best-fitting probability distributions for historical inflation-adjusted crop prices and specified triangular probability distributions for crop enterprise costs are used to simulate 100 values for crop prices and crop enterprise costs. Averaged over all crop enterprises, farm sizes, and soil types, simulated net return per ha averaged over all crop enterprises decreased 24% and simulated mean NFI for APSs decreased 57% between the historical and future climate periods. Although adapting APSs to future climate change is advantageous (i.e., NFI with adaptation is superior to NFI without adaptation based on SERF), in six of the nine cases in which adaptation is advantageous, NFI with adaptation in the future climate period is inferior to NFI in the historical climate period. Therefore, adaptation of APSs to future climate change in Flathead Valley is insufficient to offset the adverse impacts on NFI of such change.

The stem canker (blackleg) fungus, Leptosphaeria maculans, enters the genomic era.

PubMed

Rouxel, T; Balesdent, M H

2005-05-01

SUMMARY Leptosphaeria maculans is the most ubiquitous pathogen of Brassica crops, and mainly oilseed brassicas (oilseed rape, canola), causing the devastating 'stem canker' or 'blackleg'. This review summarizes our current knowledge on the pathogen, from taxonomic issues to specific life traits. It mainly illustrates the importance of formal genetics approaches on the pathogen side to dissect the interaction with the host plants. In addition, this review presents the main current research topics on L. maculans and focuses on the L. maculans genome initiative recently begun, including its main research issues. Leptosphaeria maculans (Desm.) Ces. & de Not. (anamorph Phoma lingam Tode ex Fr.). Kingdom Fungi, Phylum Ascomycota, Class Dothideomycetes (Loculoascomycetes), Order Pleosporales, Genus Leptosphaeria, Species maculans. cultivated Brassicas such as Brassica napus (oilseed rape, canola), B. rapa, B. juncea, B. oleracea, etc., along with numerous wild crucifers species. Arabidopsis thaliana was recently reported to be a potential host for L. maculans. Primary disease symptoms are greyish-green collapse of cotyledon or leaf tissue, without a visible margin, bearing tiny black spots (pycnidia). The fungus then develops an endophytic symptomless growth for many months. Secondary symptoms, at the end of the growing season, are dry necroses of the crown tissues with occasional blackening (stem canker or blackleg) causing lodging of the plants. Pseudothecia differentiate on leftover residues. Seedling damping-off and premature ripening are also reported under certain environmental conditions. Leptosphaeria maculans sequencing project at Genoscope: http://www.genoscope.cns.fr/externe/English/Projets/Projet_DM/organisme_DM.html; the SECURE site: http://www.secure.rothamsted.ac.uk/ the 'Blackleg' group at the University of Melbourne: http://www.botany.unimelb.edu.au/blackleg/overview.htm.

Identified recreation opportunities and preferences for the lower Penobscot River, Maine

Treesearch

Milton J. Fusselman; Joanne Tynon

1995-01-01

The Penobscot River has been the focus of a major Atlantic Salmon restoration effort for the last 25 years. The river has received national and international attention with the proposal of an additional 38-megawatt hydroelectric facility on its main stem. This study was conducted in response to a need to identify recreation enhancement and mitigation options related to...

Original and regenerating lizard tail cartilage contain putative resident stem/progenitor cells.

PubMed

Alibardi, Lorenzo

2015-11-01

Regeneration of cartilaginous tissues is limited in mammals but it occurs with variable extension in lizards (reptiles), including in their vertebrae. The ability of lizard vertebrae to regenerate cartilaginous tissue that is later replaced with bone has been analyzed using tritiated thymidine autoradiography and 5BrdU immunocytochemistry after single pulse or prolonged-pulse and chase experiments. The massive cartilage regeneration that can restore broad vertebral regions and gives rise to a long cartilaginous tube in the regenerating tail, depends from the permanence of some chondrogenic cells within adult vertebrae. Few cells that retain tritiated thymidine or 5-bromodeoxy-uridine for over 35 days are mainly localized in the inter-vertebral cartilage and in sparse chondrogenic regions of the neural arch of the vertebrae, suggesting that they are putative resident stem/progenitor cells. The study supports previous hypothesis indicating that the massive regeneration of the cartilaginous tissue in damaged vertebrae and in the regenerating tail of lizards derive from resident stem cells mainly present in the cartilaginous areas of the vertebrae including in the perichondrium that are retained in adult lizards as growing centers for most of their lifetime. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of a precipitation-runoff model to simulate unregulated streamflow in the South Fork Flathead River Basin, Montana

USGS Publications Warehouse

Chase, K.J.

2011-01-01

This report documents the development of a precipitation-runoff model for the South Fork Flathead River Basin, Mont. The Precipitation-Runoff Modeling System model, developed in cooperation with the Bureau of Reclamation, can be used to simulate daily mean unregulated streamflow upstream and downstream from Hungry Horse Reservoir for water-resources planning. Two input files are required to run the model. The time-series data file contains daily precipitation data and daily minimum and maximum air-temperature data from climate stations in and near the South Fork Flathead River Basin. The parameter file contains values of parameters that describe the basin topography, the flow network, the distribution of the precipitation and temperature data, and the hydrologic characteristics of the basin soils and vegetation. A primary-parameter file was created for simulating streamflow during the study period (water years 1967-2005). The model was calibrated for water years 1991-2005 using the primary-parameter file. This calibration was further refined using snow-covered area data for water years 2001-05. The model then was tested for water years 1967-90. Calibration targets included mean monthly and daily mean unregulated streamflow upstream from Hungry Horse Reservoir, mean monthly unregulated streamflow downstream from Hungry Horse Reservoir, basin mean monthly solar radiation and potential evapotranspiration, and daily snapshots of basin snow-covered area. Simulated streamflow generally was in better agreement with observed streamflow at the upstream gage than at the downstream gage. Upstream from the reservoir, simulated mean annual streamflow was within 0.0 percent of observed mean annual streamflow for the calibration period and was about 2 percent higher than observed mean annual streamflow for the test period. Simulated mean April-July streamflow upstream from the reservoir was about 1 percent lower than observed streamflow for the calibration period and about 4 percent higher than observed for the test period. Downstream from the reservoir, simulated mean annual streamflow was 17 percent lower than observed streamflow for the calibration period and 12 percent lower than observed streamflow for the test period. Simulated mean April-July streamflow downstream from the reservoir was 13 percent lower than observed streamflow for the calibration period and 6 percent lower than observed streamflow for the test period. Calibrating to solar radiation, potential evapotranspiration, and snow-covered area improved the model representation of evapotranspiration, snow accumulation, and snowmelt processes. Simulated basin mean monthly solar radiation values for both the calibration and test periods were within 9 percent of observed values except during the month of December (28 percent different). Simulated basin potential evapotranspiration values for both the calibration and test periods were within 10 percent of observed values except during the months of January (100 percent different) and February (13 percent different). The larger percent errors in simulated potential evaporation occurred in the winter months when observed potential evapotranspiration values were very small; in January the observed value was 0.000 inches and in February the observed value was 0.009 inches. Simulated start of melting of the snowpack occurred at about the same time as observed start of melting. The simulated snowpack accumulated to 90-100 percent snow-covered area 1 to 3 months earlier than observed snowpack. This overestimated snowpack during the winter corresponded to underestimated streamflow during the same period. In addition to the primary-parameter file, four other parameter files were created: for a "recent" period (1991-2005), a historical period (1967-90), a "wet" period (1989-97), and a "dry" period (1998-2005). For each data file of projected precipitation and air temperature, a single parameter file can be used to simulate a s

Ground-water resources of Sheridan County, Wyoming

USGS Publications Warehouse

Lowry, Marlin E.; Cummings, T. Ray

1966-01-01

Sheridan County is in the north-central part of Wyoming and is an area of about 2,500 square miles. The western part of the county is in the Bighorn Mountains, and the eastern part is in the Powder River structural basin. Principal streams are the Powder and Tongue Rivers, which are part of the Yellowstone River system. The climate is semiarid, and the mean annual precipitation at Sheridan is about 16 inches. Rocks of Precambrian age are exposed in the central part of the Bighorn Mountains, and successively younger rocks are exposed eastward. Rocks of Tertiary age, which are the most widespread, are exposed throughout a large part of the Powder River structural basin. Deposits of Quaternary age underlie the flood plains and terraces along the larger streams, particularly in the western part of the basin. Aquifers of pre-Tertiary age are exposed in the western part of the county, but they dip steeply and are deeply buried just a few miles east of their outcrop. Aquifers that might yield large supplies of water include the Bighorn Dolomite, Madison Limestone, Amsden Formation, and Tensleep Sandstone. The Flathead Sandstone, Sundance Formation, Morrison Formation, Cloverly Formation,. Newcastle Sandstone, Frontier Formation, Parkman Sandstone, Bearpaw Shale, .and Lance Formation may yield small or, under favorable conditions, moderate supplies of water. Few wells tap aquifers of pre-Tertiary age, and these are restricted to the outcrop area. The meager data available indicate that the water from the Lance Formation, Bearpaw Shale, Parkman Sandstone, Tensleep Sandstone and Amsden Formation, and Flathead Standstone is of suitable quality for domestic or stock purposes, and that water from the Tensleep Sandstone and Amsden Formation and the Flathead Sandstone is of good quality for irrigation. Samples could not be obtained from other aquifers of pre-Tertiary age; so the quality of water in these aquifers could not be determined. Adequate supplies of ground water for stock or domestic use can be developed throughout much of the report area from the Fort Union and Wasatch Formations of Tertiary age; larger supplies might be obtained from the coarse-grained sandstone facies of the Wasatch Formation near Moncreiffe Ridge. Four aquifer tests were made at wells tapping formations of Tertiary age, and the coefficients of permeability determined ranged from 2.5 to 7.9 gallons per day per square foot. The depths to which wells must be drilled to penetrate an aquifer differ within relatively short distances because of the lenticularity of the aquifers. Water in aquifers of Tertiary age may occur under water-table, artesian, or a combination of artesian and gas-lift conditions. Water from the Fort Union is usable for domestic purposes, but the iron and dissolved-solids content impair the quality at some localities. Water from the Fort Union Formation is not recommended for irrigation because of sodium and bicarbonate content. The water is regarded as good to fair for stock use. Water from the Wasatch Formation generally contains dissolved solids in excess of the suggested domestic standards, but this water is usable in the absence of other supplies. The development of irrigation supplies from the Wasatch Formation may be possible in some areas, but the water quality should be carefully checked. Water of good to very poor quality for stock supplies is obtained, depending upon the location. Hydrogen sulfide, commonly present in water of the Fort Union and Wasatch Formations, becomes an objectionable characteristic when the water is used for human consumption. Deposits of Quaternary age generally yield small to moderate supplies of water to wells. Two pumping tests were conducted, and the coefficients of permeability of the aquifers tested were 380 and 1,100 gallons per day per square foot. Usable supplies of ground water can be developed from the deposits of Quaternary age, principally along the valleys of perennial strea

Modeling Human Neurological and Neurodegenerative Diseases: From Induced Pluripotent Stem Cells to Neuronal Differentiation and Its Applications in Neurotrauma.

PubMed

Bahmad, Hisham; Hadadeh, Ola; Chamaa, Farah; Cheaito, Katia; Darwish, Batoul; Makkawi, Ahmad-Kareem; Abou-Kheir, Wassim

2017-01-01

With the help of several inducing factors, somatic cells can be reprogrammed to become induced pluripotent stem cell (iPSCs) lines. The success is in obtaining iPSCs almost identical to embryonic stem cells (ESCs), therefore various approaches have been tested and ultimately several ones have succeeded. The importance of these cells is in how they serve as models to unveil the molecular pathways and mechanisms underlying several human diseases, and also in its potential roles in the development of regenerative medicine. They further aid in the development of regenerative medicine, autologous cell therapy and drug or toxicity screening. Here, we provide a comprehensive overview of the recent development in the field of iPSCs research, specifically for modeling human neurological and neurodegenerative diseases, and its applications in neurotrauma. These are mainly characterized by progressive functional or structural neuronal loss rendering them extremely challenging to manage. Many of these diseases, including Parkinson's disease (PD), Huntington's disease (HD), Amyotrophic lateral sclerosis (ALS) and Alzheimer's disease (AD) have been explored in vitro . The main purpose is to generate patient-specific iPS cell lines from the somatic cells that carry mutations or genetic instabilities for the aim of studying their differentiation potential and behavior. This new technology will pave the way for future development in the field of stem cell research anticipating its use in clinical settings and in regenerative medicine in order to treat various human diseases, including neurological and neurodegenerative diseases.

7 CFR 51.910 - Straggly.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Standards for Grades of Table Grapes (European or Vinifera Type) 1 Definitions § 51.910 Straggly. Straggly means that the berries are so widely spaced on main and laterial stems that the bunch is distinctly open...

7 CFR 51.910 - Straggly.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Standards for Grades of Table Grapes (European or Vinifera Type) 1 Definitions § 51.910 Straggly. Straggly means that the berries are so widely spaced on main and laterial stems that the bunch is distinctly open...

7 CFR 51.910 - Straggly.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Standards for Grades of Table Grapes (European or Vinifera Type) 1 Definitions § 51.910 Straggly. Straggly means that the berries are so widely spaced on main and laterial stems that the bunch is distinctly open...

Selenium in the upper Blackfoot River watershed, southeastern Idaho, 2001-12

USGS Publications Warehouse

Mebane, Christopher A.; Mladenka, Greg; Van Every, Lynn; Williams, Marshall L.; Hardy, Mark A.; Garbarino, John R.

2014-11-05

For the annual spring synoptic samples collected by the IDEQ along the main stem Blackfoot River and major tributaries, selenium concentrations ranged from less than 2 to 870 μg/L in 176 samples. In most years, the synoptic sampling showed that the majority of the selenium loads passing the USGS streamgage at the outlet of the watershed could be attributed to a single tributary, East Mill Creek, which enters the Blackfoot River through Spring Creek. Selenium loads decreased by about half from East Mill Creek before reaching the Blackfoot River, suggesting that much selenium is at least temporarily removed from the water column by uptake by aquatic vegetation or by losses to sediment. Similar decreases in selenium loads occurred through the main stem Blackfoot River before reaching the outlet in low flow years, but not in high flow years.

Immediate flow reserve of Y thoracic artery grafts: an intraoperative flowmetric study.

PubMed

Gaudino, Mario; Di Mauro, Michele; Iacò, Angela Lorena; Canosa, Carlo; Vitolla, Giuseppe; Calafiore, Antonio Maria

2003-10-01

Use of both internal thoracic arteries in a Y graft configuration can raise concerns about the possibility of the single left internal thoracic artery being able to meet the flow requirements of two or three distal territories. We evaluated intraoperatively the flow reserve of a Y thoracic artery graft distally anastomosed to the anterior and lateral territories. In 21 patients who had Y thoracic artery grafts, the flow was measured in the main stem of the left internal thoracic artery, in the left internal thoracic artery branch, and in the right internal thoracic artery. A transit time Doppler flowmeter was used. Measurements were repeated after the injection of a bolus of 20 mug/kg dobutamine. At baseline condition, the mean blood flow was 44.8 +/- 24.2, 23.4 +/- 11.5, and 21.4 +/- 15.3 mL/min in the main stem of the left internal thoracic artery, in the left internal thoracic artery branch, and in the right internal thoracic artery, respectively. After dobutamine injection, these values increased to 93.2 +/- 49.8, 46.1 +/- 22.6, and 42.5 +/- 31.2 mL/min, respectively. Flow reserve was 2.1 +/- 0.6, 2.2 +/- 0.9, and 2.1 +/- 0.9 mL/min, respectively. Intraoperative injection of dobutamine increases the flow in the Y thoracic graft by more than two times, not only in the main stem but also in each branch. This finding attests to the safety of Y thoracic conduits in terms of hemodynamic potential.

Important photosynthetic contribution from the non-foliar green organs in cotton at the late growth stage.

PubMed

Hu, Yuan-Yuan; Zhang, Ya-Li; Luo, Hong-Hai; Li, Wei; Oguchi, Riichi; Fan, Da-Yong; Chow, Wah Soon; Zhang, Wang-Feng

2012-02-01

Non-foliar green organs are recognized as important carbon sources after leaves. However, the contribution of each organ to total yield has not been comprehensively studied in relation to the time-course of changes in surface area and photosynthetic activity of different organs at different growth stages. We studied the contribution of leaves, main stem, bracts and capsule wall in cotton by measuring their time-course of surface area development, O(2) evolution capacity and photosynthetic enzyme activity. Because of the early senescence of leaves, non-foliar organs increased their surface area up to 38.2% of total at late growth stage. Bracts and capsule wall showed less ontogenetic decrease in O(2) evolution capacity per area and photosynthetic enzyme activity than leaves at the late growth stage. The total capacity for O(2) evolution of stalks and bolls (bracts plus capsule wall) was 12.7 and 23.7% (total ca. 36.4%), respectively, as estimated by multiplying their surface area by their O(2) evolution capacity per area. We also kept the bolls (from 15 days after anthesis) or main stem (at the early full bolling stage) in darkness for comparison with non-darkened controls. Darkening the bolls and main stem reduced the boll weight by 24.1 and 9%, respectively, and the seed weight by 35.9 and 16.3%, respectively. We conclude that non-foliar organs significantly contribute to the yield at the late growth stage.

Tradeoffs in Greenhouse Gas Fluxes from Aquatic Ecosystems Along a Rural to Urban Gradient are Driven by N Loading

NASA Astrophysics Data System (ADS)

McDowell, W. H.; Potter, J.

2017-12-01

The effects of urbanization on net greenhouse gas (GHG) exchange from streams and rivers to the atmosphere are poorly understood. Previous work on a few small suburban streams in New Hampshire shows that N2O concentration is strongly seasonal, increases with wetland contact, and can be highest in streams with low CH4 production. Here we expand on these observations using 4 years of weekly samples in multiple headwater streams and a single downstream main stem site. Our results show that within a single drainage network, CH4 concentrations are higher downstream than in any of the small tributaries studied, which span a range of land use and wetland coverage. Methane is also very strongly seasonal in concentration in the tributaries (peaking in late summer), but is aseasonal in the main stem. In contrast, N2O concentrations are strongly seasonal at all sites, but peak in early winter and are much higher in more urban tributaries than the main stem. Urbanization results in a flipping of GHG concentrations, with highest N2O and lowest CH4 in the most urban watershed. CO2 shows no strong patterns with respect to landscape position, urbanization, or season. We examined multiple biogeochemical drivers of net CH4 and N2O production, and found that the increased NO3 concentration associated with urbanization is a good predictor of N2O concentrations in many streams.

Behavior and movements of adult spring Chinook salmon (Oncorhynchus tshawytscha) in the Chehalis River Basin, southwestern Washington, 2015

USGS Publications Warehouse

Liedtke, Theresa L.; Zimmerman, Mara S.; Tomka, Ryan G.; Holt, Curt; Jennings, Lyle

2016-09-14

Recent interest in flood control and restoration strategies in the Chehalis River Basin has increased the need to understand the current status and ecology of spring Chinook salmon. Based on the extended period between freshwater entry and spawn timing, spring Chinook salmon have the longest exposure of all adult Chinook salmon life histories to the low-flow and high water temperature conditions that typically occur during summer. About 100 adult spring Chinook salmon were found dead in the Chehalis River in July and August 2009. Adult Chinook salmon are known to hold in cool-water refugia during warm summer months, but the extent to which spring Chinook salmon might use thermal refugia in the Chehalis River is unknown. The movements and temperature exposures of adult spring Chinook salmon following their return to the Chehalis River were investigated using radiotelemetry and transmitters equipped with temperature sensors, combined with water temperature monitoring throughout the basin. A total of 23 spring Chinook salmon were radio-tagged between April and early July 2015; 11 were captured and released in the main-stem Chehalis River, and 12 were captured and released in the South Fork Newaukum River. Tagged fish were monitored with a combination of fixed-site monitoring locations and regular mobile tracking, from freshwater entry through the spawning period.Water temperature and flow conditions in the main-stem Chehalis River during 2015 were atypical compared to historical averages. Mean monthly water temperatures between March and July 2015 were higher than any decade since 1960 and mean daily flows were 30–70 percent of the flows in previous years. Overall, 96 percent of the tagged fish were detected, with a mean of 62 d in the detection history of tagged fish. Of the 11 fish released in the main-stem Chehalis River, six fish (55 percent) moved upstream, either shortly after release (2–7 d, 50 percent), or following a short delay (12–18 d, 50 percent). One fish released in the main-stem Chehalis River remained near the release location for 64 d before moving upstream.The final fates for the seven fish that moved upstream in the main-stem Chehalis River included two fish with unknown fates, two fish with a fate of pre-spawn mortality, and three fish that were assigned a fate of spawner. Four (36 percent) of the radio-tagged Chinook salmon released in the main-stem Chehalis River showed limited movement from their release sites, and were assigned fates of unknown (one fish), pre-spawn mortality (one fish), and spit/mortality (2 fish). The 12 spring Chinook salmon released in the South Fork Newaukum River remained in the South Fork Newaukum River throughout the study period. Five (42 percent) of these fish were actively moving through the spawning period and were assigned a fate of spawner. Seven (58 percent) of these fish were detected for a period following release, but their detection histories ended prior to the spawning period. The fates assigned to these seven fish included two fish with spit/mortality fates and five fish with fates of pre-spawn mortality. Tagged fish in both the Chehalis River and the South Fork Newaukum River showed limited movements during the peak water temperatures in July and August, and were not frequently detected at sites where water temperatures were greater than 21 °C. Pre-spawn mortality due to predation or harvest may be an important factor in the Chehalis River Basin as it was the assigned fate for 27 percent of the fish released in the main-stem Chehalis River and 42 percent of the fish released in the South Fork Newaukum River.This study represents a substantial contribution to the understanding of spring Chinook salmon in the Chehalis River Basin. The water temperatures and flow conditions during the 2015 study period were not typical of the historical conditions in the basin and the numbers of tagged fish monitored was relatively low, so results should be interpreted with those cautions in mind.

[Proliferation and osteogenic differentiation of mesenchymal stem cells in hydrogels of human blood plasma].

PubMed

Linero, Itali M; Doncel, Adriana; Chaparro, Orlando

2014-01-01

The use of mesenchymal stem cells in clinical practice has increased considerably in the last decade because they play a supporting role in the processes of tissue repair and regeneration, becoming the main tool of cell therapy for the treatment of diseases functionally affecting bone and cartilage tissue . To evaluate in vitro the proliferative and osteogenic differentiation ability of mesenchymal stem cells derived from human adipose tissue in a blood plasma hydrogel. Mesenchymal stem cells were obtained from human adipose tissue explants and characterized by flow cytometry. Their multipotentiality was demonstrated by their ability to differentiate to adipogenic and osteogenic lineages. Cell proliferation and osteogenic differentiation ability of the cells cultured in blood plasma hydrogels were also evaluated. Mesenchymal stem cells derived from human adipose tissue growing in human blood plasma hydrogels showed a pattern of proliferation similar to that of the cells cultured in monolayer and also maintained their ability to differentiate to osteogenic lineage. Human blood plasma hydrogels are a suitable support for proliferation and osteogenic differentiation of mesenchymal stem cells derived from human adipose tissue and provides a substrate that is autologous, biocompatible, reabsorbable, easy to use, potentially injectable and economic, which could be used as a successful strategy for the management and clinical application of cell therapy in regenerative medicine.

Correlated miR-mRNA expression signatures of mouse hematopoietic stem and progenitor cell subsets predict "Stemness" and "Myeloid" interaction networks.

PubMed

Heiser, Diane; Tan, Yee Sun; Kaplan, Ian; Godsey, Brian; Morisot, Sebastien; Cheng, Wen-Chih; Small, Donald; Civin, Curt I

2014-01-01

Several individual miRNAs (miRs) have been implicated as potent regulators of important processes during normal and malignant hematopoiesis. In addition, many miRs have been shown to fine-tune intricate molecular networks, in concert with other regulatory elements. In order to study hematopoietic networks as a whole, we first created a map of global miR expression during early murine hematopoiesis. Next, we determined the copy number per cell for each miR in each of the examined stem and progenitor cell types. As data is emerging indicating that miRs function robustly mainly when they are expressed above a certain threshold (∼100 copies per cell), our database provides a resource for determining which miRs are expressed at a potentially functional level in each cell type. Finally, we combine our miR expression map with matched mRNA expression data and external prediction algorithms, using a Bayesian modeling approach to create a global landscape of predicted miR-mRNA interactions within each of these hematopoietic stem and progenitor cell subsets. This approach implicates several interaction networks comprising a "stemness" signature in the most primitive hematopoietic stem cell (HSC) populations, as well as "myeloid" patterns associated with two branches of myeloid development.

Unraveling the non-senescence phenomenon in Hydra.

PubMed

Dańko, Maciej J; Kozłowski, Jan; Schaible, Ralf

2015-10-07

Unlike other metazoans, Hydra does not experience the distinctive rise in mortality with age known as senescence, which results from an increasing imbalance between cell damage and cell repair. We propose that the Hydra controls damage accumulation mainly through damage-dependent cell selection and cell sloughing. We examine our hypothesis with a model that combines cellular damage with stem cell renewal, differentiation, and elimination. The Hydra individual can be seen as a large single pool of three types of stem cells with some features of differentiated cells. This large stem cell community prevents "cellular damage drift," which is inevitable in complex conglomerate (differentiated) metazoans with numerous and generally isolated pools of stem cells. The process of cellular damage drift is based on changes in the distribution of damage among cells due to random events, and is thus similar to Muller's ratchet in asexual populations. Events in the model that are sources of randomness include budding, cellular death, and cellular damage and repair. Our results suggest that non-senescence is possible only in simple Hydra-like organisms which have a high proportion and number of stem cells, continuous cell divisions, an effective cell selection mechanism, and stem cells with the ability to undertake some roles of differentiated cells. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Semantic transparency in free stems: The effect of Orthography-Semantics Consistency on word recognition.

PubMed

Marelli, Marco; Amenta, Simona; Crepaldi, Davide

2015-01-01

A largely overlooked side effect in most studies of morphological priming is a consistent main effect of semantic transparency across priming conditions. That is, participants are faster at recognizing stems from transparent sets (e.g., farm) in comparison to stems from opaque sets (e.g., fruit), regardless of the preceding primes. This suggests that semantic transparency may also be consistently associated with some property of the stem word. We propose that this property might be traced back to the consistency, throughout the lexicon, between the orthographic form of a word and its meaning, here named Orthography-Semantics Consistency (OSC), and that an imbalance in OSC scores might explain the "stem transparency" effect. We exploited distributional semantic models to quantitatively characterize OSC, and tested its effect on visual word identification relying on large-scale data taken from the British Lexicon Project (BLP). Results indicated that (a) the "stem transparency" effect is solid and reliable, insofar as it holds in BLP lexical decision times (Experiment 1); (b) an imbalance in terms of OSC can account for it (Experiment 2); and (c) more generally, OSC explains variance in a large item sample from the BLP, proving to be an effective predictor in visual word access (Experiment 3).

Synergy of multi-scale toughening and protective mechanisms at hierarchical branch-stem interfaces

NASA Astrophysics Data System (ADS)

Müller, Ulrich; Gindl-Altmutter, Wolfgang; Konnerth, Johannes; Maier, Günther A.; Keckes, Jozef

2015-09-01

Biological materials possess a variety of artful interfaces whose size and properties are adapted to their hierarchical levels and functional requirements. Bone, nacre, and wood exhibit an impressive fracture resistance based mainly on small crystallite size, interface organic adhesives and hierarchical microstructure. Currently, little is known about mechanical concepts in macroscopic biological interfaces like the branch-stem junction with estimated 1014 instances on earth and sizes up to few meters. Here we demonstrate that the crack growth in the upper region of the branch-stem interface of conifer trees proceeds along a narrow predefined region of transversally loaded tracheids, denoted as sacrificial tissue, which fail upon critical bending moments on the branch. The specific arrangement of the tracheids allows disconnecting the overloaded branch from the stem in a controlled way by maintaining the stem integrity. The interface microstructure based on the sharply adjusted cell orientation and cell helical angle secures a zig-zag crack propagation path, mechanical interlock closing after the bending moment is removed, crack gap bridging and self-repairing by resin deposition. The multi-scale synergetic concepts allows for a controllable crack growth between stiff stem and flexible branch, as well as mechanical tree integrity, intact physiological functions and recovery after the cracking.

Stem Cell-Like Differentiation Potentials of Endometrial Side Population Cells as Revealed by a Newly Developed In Vivo Endometrial Stem Cell Assay

PubMed Central

Miyazaki, Kaoru; Maruyama, Tetsuo; Masuda, Hirotaka; Yamasaki, Akiko; Uchida, Sayaka; Oda, Hideyuki; Uchida, Hiroshi; Yoshimura, Yasunori

2012-01-01

Background Endometrial stem/progenitor cells contribute to the cyclical regeneration of human endometrium throughout a woman's reproductive life. Although the candidate cell populations have been extensively studied, no consensus exists regarding which endometrial population represents the stem/progenitor cell fraction in terms of in vivo stem cell activity. We have previously reported that human endometrial side population cells (ESP), but not endometrial main population cells (EMP), exhibit stem cell-like properties, including in vivo reconstitution of endometrium-like tissues when xenotransplanted into immunodeficient mice. The reconstitution efficiency, however, was low presumably because ESP cells alone could not provide a sufficient microenvironment (niche) to support their stem cell activity. The objective of this study was to establish a novel in vivo endometrial stem cell assay employing cell tracking and tissue reconstitution systems and to examine the stem cell properties of ESP through use of this assay. Methodology/Principal Findings ESP and EMP cells isolated from whole endometrial cells were infected with lentivirus to express tandem Tomato (TdTom), a red fluorescent protein. They were mixed with unlabeled whole endometrial cells and then transplanted under the kidney capsule of ovariectomized immunodeficient mice. These mice were treated with estradiol and progesterone for eight weeks and nephrectomized. All of the grafts reconstituted endometrium-like tissues under the kidney capsules. Immunofluorescence revealed that TdTom-positive cells were significantly more abundant in the glandular, stromal, and endothelial cells of the reconstituted endometrium in mice transplanted with TdTom-labeled ESP cells than those with TdTom-labeled EMP cells. Conclusions/Significance We have established a novel in vivo endometrial stem cell assay in which multi-potential differentiation can be identified through cell tracking during in vivo endometrial tissue reconstitution. Using this assay, we demonstrated that ESP cells differentiated into multiple endometrial lineages in the niche provided by whole endometrial cells, indicating that ESP cells are genuine endometrial stem/progenitor cells. PMID:23226538

Co-culture of Adult Mesenchymal Stem Cells and Nucleus Pulposus Cells in Bilaminar Pellets for Intervertebral Disc Regeneration.

PubMed

Allon, Aliza A; Schneider, Richard A; Lotz, Jeffrey C

2009-01-01

Our goal is to optimize stem cell-based tissue engineering strategies in the context of the intervertebral disc environment. We explored the benefits of co-culturing nucleus pulposus cells (NPC) and adult mesenchymal stem cells (MSC) using a novel spherical bilaminar pellet culture system where one cell type is enclosed in a sphere of the other cell type. Our 3D system provides a structure that exploits embryonic processes such as tissue induction and condensation. We observed a unique phenomenon: the budding of co-culture pellets and the formation of satellite pellets that separate from the main pellet. MSC and NPC co-culture pellets were formed with three different structural organizations. The first had random organization. The other two had bilaminar organization with either MSC inside and NPC outside or NPC inside and MSC outside. By 14 days, all co-culture pellets exhibited budding and spontaneously generated satellite pellets. The satellite pellets were composed of both cell types and, surprisingly, all had the same bilaminar organization with MSC on the inside and NPC on the outside. This organization was independent of the structure of the main pellet that the satellites stemmed from. The main pellets generated satellite pellets that spontaneously organized into a bilaminar structure. This implies that structural organization occurs naturally in this cell culture system and may be inherently favorable for cell-based tissue engineering strategies. The occurrence of budding and the organization of satellite pellets may have important implications for the use of co-culture pellets in cell-based therapies for disc regeneration. From a therapeutic point of view, the generation of satellite pellets may be a beneficial feature that would serve to spread donor cells throughout the host matrix and restore normal matrix composition in a sustainable way, ultimately renewing tissue function.

Continuous myocloni and tonic spasms in a 2-month-old infant with enterovirus 71 brain stem encephalitis.

PubMed

Lee, Kyung Yeon; Yeh, Hye-Ryun

2015-02-01

Brain stem encephalitis is a cardinal presentation of central nervous system involvement in enterovirus 71 infection, and manifests as myoclonus, ataxia, tremor, and autonomic dysfunction. A 2-month-old infant with enterovirus 71 brain stem encephalitis demonstrated continuous myocloni and tonic spasms. On admission, the patient's myoclonus, which mainly involved the shoulders and the arms, was considerably worse during wakefulness and occurred once or twice a minute. Several hours after admission, the myoclonic jerks steadily worsened, appeared ceaselessly every 1 to 2 seconds, and were intermixed with tonic spasms of all four extremities accompanied by crying. Video electroencephalography revealed a normal background without epileptiform discharges and no ictal electroencephalographic changes during the myoclonic jerks and tonic spasms. Complete remission was achieved without complications after completion of a 3-day immunoglobulin therapy. This case suggests that the brain stem may be a major origin site for not only myoclonus but also tonic spasm. Georg Thieme Verlag KG Stuttgart · New York.

Science identity possibilities: a look into Blackness, masculinities, and economic power relations

NASA Astrophysics Data System (ADS)

Rosa, Katemari

2018-02-01

This forum paper dialogues with Sheron Mark's A bit of both science and economics: a non-traditional STEM identity narrative. In her paper, she discusses the development of a Science, Technology, Engineering, and Mathematics (STEM) identity by a young African American male during an informal STEM for Social Justice Program. Here, the discussion focuses on Black masculinities, identity formation, and the role of science educators in making STEM fields a welcoming place for young Black men. Drawing from Mark's data and discussion, this paper is a dialogue between science identity possibilities in the United States and in Brazil when we look at the intersections of race, gender, and socioeconomic status. Using the shared colonial past of both countries a connection is established to address race relations within science education. The main argument in this paper is that racism can no longer be denied and dismissed by the science education community worldwide and that intersectional approaches are needed to face this issue.

The RNA-binding protein repertoire of embryonic stem cells.

PubMed

Kwon, S Chul; Yi, Hyerim; Eichelbaum, Katrin; Föhr, Sophia; Fischer, Bernd; You, Kwon Tae; Castello, Alfredo; Krijgsveld, Jeroen; Hentze, Matthias W; Kim, V Narry

2013-09-01

RNA-binding proteins (RBPs) have essential roles in RNA-mediated gene regulation, and yet annotation of RBPs is limited mainly to those with known RNA-binding domains. To systematically identify the RBPs of embryonic stem cells (ESCs), we here employ interactome capture, which combines UV cross-linking of RBP to RNA in living cells, oligo(dT) capture and MS. From mouse ESCs (mESCs), we have defined 555 proteins constituting the mESC mRNA interactome, including 283 proteins not previously annotated as RBPs. Of these, 68 new RBP candidates are highly expressed in ESCs compared to differentiated cells, implicating a role in stem-cell physiology. Two well-known E3 ubiquitin ligases, Trim25 (also called Efp) and Trim71 (also called Lin41), are validated as RBPs, revealing a potential link between RNA biology and protein-modification pathways. Our study confirms and expands the atlas of RBPs, providing a useful resource for the study of the RNA-RBP network in stem cells.

Chemically Induced Reprogramming of Somatic Cells to Pluripotent Stem Cells and Neural Cells.

PubMed

Biswas, Dhruba; Jiang, Peng

2016-02-06

The ability to generate transplantable neural cells in a large quantity in the laboratory is a critical step in the field of developing stem cell regenerative medicine for neural repair. During the last few years, groundbreaking studies have shown that cell fate of adult somatic cells can be reprogrammed through lineage specific expression of transcription factors (TFs)-and defined culture conditions. This key concept has been used to identify a number of potent small molecules that could enhance the efficiency of reprogramming with TFs. Recently, a growing number of studies have shown that small molecules targeting specific epigenetic and signaling pathways can replace all of the reprogramming TFs. Here, we provide a detailed review of the studies reporting the generation of chemically induced pluripotent stem cells (ciPSCs), neural stem cells (ciNSCs), and neurons (ciN). We also discuss the main mechanisms of actions and the pathways that the small molecules regulate during chemical reprogramming.

Accelerated generation of oligodendrocyte progenitor cells from human induced pluripotent stem cells by forced expression of Sox10 and Olig2.

PubMed

Li, Pengyan; Li, Mo; Tang, Xihe; Wang, Shuyan; Zhang, Y Alex; Chen, Zhiguo

2016-11-01

Oligodendrocyte progenitor cells (OPCs) hold great promise for treatment of dysmyelinating disorders, such as multiple sclerosis and cerebral palsy. Recent studies on generation of human OPCs mainly use human embryonic stem cells (hESCs) or neural stem cells (NSCs) as starter cell sources for the differentiation process. However, NSCs are restricted in availability and the present method for generation of oligodendrocytes (OLs) from ESCs often requires a lengthy period of time. Here, we demonstrated a protocol to efficiently derive OPCs from human induced pluripotent stem cells (hiPSCs) by forced expression of two transcription factors (2TFs), Sox10 and Olig2. With this method, PDGFRα + OPCs can be obtained in 14 days and O4 + OPCs in 56 days. Furthermore, OPCs may be able to differentiate to mature OLs that could ensheath axons when co-cultured with rat cortical neurons. The results have implications in the development of autologous cell therapies.

The quantitative proteomes of human-induced pluripotent stem cells and embryonic stem cells

PubMed Central

Munoz, Javier; Low, Teck Y; Kok, Yee J; Chin, Angela; Frese, Christian K; Ding, Vanessa; Choo, Andre; Heck, Albert J R

2011-01-01

Assessing relevant molecular differences between human-induced pluripotent stem cells (hiPSCs) and human embryonic stem cells (hESCs) is important, given that such differences may impact their potential therapeutic use. Controversy surrounds recent gene expression studies comparing hiPSCs and hESCs. Here, we present an in-depth quantitative mass spectrometry-based analysis of hESCs, two different hiPSCs and their precursor fibroblast cell lines. Our comparisons confirmed the high similarity of hESCs and hiPSCS at the proteome level as 97.8% of the proteins were found unchanged. Nevertheless, a small group of 58 proteins, mainly related to metabolism, antigen processing and cell adhesion, was found significantly differentially expressed between hiPSCs and hESCs. A comparison of the regulated proteins with previously published transcriptomic studies showed a low overlap, highlighting the emerging notion that differences between both pluripotent cell lines rather reflect experimental conditions than a recurrent molecular signature. PMID:22108792

Changes in the sugar content of sweet sorghum stems under natural conditions during winter in saline soil of the Yellow River Delta

NASA Astrophysics Data System (ADS)

Li, Ying; Yuan, Fang; Wang, Baoshan

2018-02-01

In order to investigate the maximum storage period during their natural growth state, the sweet sorghum (Sorghum bicolor L. Moench) stems of four cultivars were analyzed to determine changes in contents of water, total sugars, main soluble sugars and the enzyme activity. From early November 2016 to late January 2017, the decrease in the total sugar content and the contents of sucrose, glucose and fructose slowed down, and the enzyme activities (sucrose synthase and sucrose phosphate synthase) involving sucrose metabolism in the stem remained stable. However, these indicators decreased significantly after the end of January 2017. Low temperatures and a dry environment were conducive to the storage of the sweet sorghum stems. During the winter (from early November 2016 to late January 2017) in northern China, the sweet sorghum plants can be stored naturally in the field via regulating sowing dates, which saves a lot of storage space and production costs for bioethanol company.

Microscopic diagnosis of the leaf and stem of Piper solmsianum C.DC.

PubMed

Bertocco, A R P; Migacz, I P; Santos, V L P; Franco, C R C; Silva, R Z; Yunes, R A; Cechinel-Filho, V; Budel, J M

2017-08-01

Piper solmsianum C.DC., which is popularly known as pariparoba, is a shrub that measures 1-3 m in height and it inhabits areas with wet tropical soils. The objective of this study was to analyze the leaf and stem anatomy using light microscopy, scanning electron micrographs, and energy-dispersive X-ray spectroscopy in order to provide information for species identification. The anatomical profile showed the following main microscopic markers: hypostomatic leaf; hypodermis layer on both sides; pearl glands; biconvex midrib shape; five collateral vascular bundles in open arc with the central bundle larger than the others; circular stem shape; collateral vascular bundles arranged in two rings; sinuous sclerenchymatic sheath in the pith; secretory idioblasts; and starch grains in the mesophyll, in the ground parenchyma of the midrib, petiole, and in the stem; and six morphotypes of calcium oxalate crystals (styloids, cuneiform, tabular crystal rosettes, cuneiform crystal rosettes, elongated square dipyramids, as well as very elongated square dipyramids). © 2017 Wiley Periodicals, Inc.

Encouraging Girls into Science and Technology with Feminine Role Model: Does This Work?

NASA Astrophysics Data System (ADS)

Bamberger, Yael M.

2014-08-01

This study examines the effect of a program that aimed to encourage girls to choose a science, technology, engineering, and mathematics (STEM) career in Israel. The program involved school visits to a high-tech company and meeting with role model female scientists. Sixty ninth-grade female students from a Jewish modern-orthodox single-sex secondary school in the same city as the company participated in the study. The control group contained 30 girls from the same classes who did not participate in the program. Data were collected through pre-post questionnaires, observations, and focus group interviews. It was analyzed for three main themes: perceptions of scientists and engineers, capability of dealing with STEM, and future career choice. Findings indicated respect toward the women scientists as being smart and creative, but significant negative change on the perceptions of women scientists/engineers, the capability of dealing with STEM, and the STEM career choices. Possible causes for these results are discussed, as well as implications for education.

Mechanisms of cellular therapy in respiratory diseases.

PubMed

Abreu, Soraia C; Antunes, Mariana A; Pelosi, Paolo; Morales, Marcelo M; Rocco, Patricia R M

2011-09-01

Stem cells present a variety of clinical implications in the lungs. According to their origin, these cells can be divided into embryonic and adult stem cells; however, due to the important ethical and safety limitations that are involved in the embryonic stem cell use, most studies have chosen to focus on adult stem cell therapy. This article aims to present and clarify the recent advances in the field of stem cell biology, as well as to highlight the effects of mesenchymal stem cell (MSC) therapy in the context of acute lung injury/acute respiratory distress syndrome and chronic disorders such as lung fibrosis and chronic obstructive pulmonary disease. For this purpose, we performed a critical review of adult stem cell therapies, covering the main clinical and experimental studies published in Pubmed databases in the past 11 years. Different characteristics were extracted from these articles, such as: the experimental model, strain, cellular type and administration route used as well as the positive or negative effects obtained. There is evidence for beneficial effects of MSC on lung development, repair, and remodeling. The engraftment in the injured lung does not occur easily, but several studies report that paracrine factors can be effective in reducing inflammation and promoting tissue repair. MSC releases several growth factors and anti-inflammatory cytokines that regulate endothelial and epithelial permeability and reduce the severity of inflammation. A better understanding of the mechanisms that control cell division and differentiation, as well as of their paracrine effects, is required to enable the optimal use of bone marrow-derived stem cell therapy to treat human respiratory diseases.

Firefighter willingness to participate in a stem cell clinical trial for burns: A mixed methods study.

PubMed

Horch, Jenny D; Carr, Eloise C J; Harasym, Patricia; Burnett, Lindsay; Biernaskie, Jeff; Gabriel, Vincent

2016-12-01

Adult stem cells represent a potentially renewable and autologous source of cells to regenerate skin and improve wound healing. Firefighters are at risk of sustaining a burn and potentially benefiting from a split thickness skin graft (STSG). This mixed methods study examined firefighter willingness to participate in a future stem cell clinical trial, outcome priorities and factors associated with this decision. A sequential explanatory mixed methods design was used. The quantitative phase (online questionnaire) was followed by the qualitative phase (semi-structured interviews). A sample of 149 firefighters completed the online survey, and a purposeful sample of 15 firefighters was interviewed. A majority (74%) reported they would participate in a future stem cell clinical trial if they experienced burn benefiting from STSG. Hypothetical concerns related to receiving a STSG were pain, itch, scarring/redness and skin durability. Participants indicated willingness to undergo stem cell therapy if the risk of no improvement was 43% or less. Risk tolerance was predicted by perceived social support and having children. Interviews revealed four main themes: a desire to help others, improving clinical outcomes, trusting relationships, and a belief in scientific investigation. Many participants admitted lacking sufficient knowledge to make an informed decision regarding stem cell therapies. Firefighters indicated they were largely willing to participate in a stem cell clinical trial but also indicated a lack of knowledge upon which to make a decision. Public education of the role of stem cells in STSG will be increasingly important as clinical trials are developed. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Leg lengthening and femoral-offset reduction after total hip arthroplasty: where is the problem - stem or cup positioning?

PubMed

Al-Amiry, Bariq; Mahmood, Sarwar; Krupic, Ferid; Sayed-Noor, Arkan

2017-09-01

Background Restoration of femoral offset (FO) and leg length is an important goal in total hip arthroplasty (THA) as it improves functional outcome. Purpose To analyze whether the problem of postoperative leg lengthening and FO reduction is related to the femoral stem or acetabular cup positioning or both. Material and Methods Between September 2010 and April 2013, 172 patients with unilateral primary osteoarthritis treated with THA were included. Postoperative leg-length discrepancy (LLD) and global FO (summation of cup and FO) were measured by two observers using a standardized protocol for evaluation of antero-posterior plain hip radiographs. Patients with postoperative leg lengthening ≥10 mm (n = 41) or with reduced global FO >5 mm (n = 58) were further studied by comparing the stem and cup length of the operated side with the contralateral side in the lengthening group, and by comparing the stem and cup offset of the operated side with the contralateral side in the FO reduction group. We evaluated also the inter-observer and intra-observer reliability of the radiological measurements. Results Both observers found that leg lengthening was related to the stem positioning while FO reduction was related to the positioning of both the femoral stem and acetabular cup. Both inter-observer reliability and intra-observer reproducibility were moderate to excellent (intra-class correlation co-efficient, ICC ≥0.69). Conclusion Post THA leg lengthening was mainly caused by improper femoral stem positioning while global FO reduction resulted from improper positioning of both the femoral stem and the acetabular cup.

Women discouraged by masculine culture in physics

NASA Astrophysics Data System (ADS)

Allen, Michael

2016-12-01

An analysis of more than 1000 papers on gender disparity in science, technology, engineering and mathematics (STEM) has revealed three main reasons why women are underrepresented in those subjects at undergraduate level in the US.

Chemical constituents of essential oils from the leaves, stems, roots and fruits of Alpinia polyantha.

PubMed

Huong, Le T; Thang, Tran D; Ogunwande, Isiaka A

2015-02-01

The essential oils obtained from the leaves, stems, roots and fruits of Alpinia polyantha D. Fang (Zingiberaceae) have been studied. The leaf oil was comprised mainly of camphor (16.1%), α-pinene (15.2%) and β-agarofuran (12.9%), while the major constituents of the stem oil were α-pinene (12.4%), β-cubebene (10.6%), β-agarofuran (10.3%) and globulol (8.8%). However, β-cubebene (12.6%), fenchyl acetate (10.8%), β-maaliene (9.0%), aristolone (8.8%) and α-pinene (8.2%) were the compounds occurring in higher amounts in the root oil. The quantitatively significant compounds of the fruit oil were δ-cadinene (10.9%), β-caryophyllene (9.1%), β-pinene (8.7%) and α-muurolene (7.7%).

Generation of transgene-free induced pluripotent stem cells with non-viral methods.

PubMed

Wang, Tao; Zhao, Hua-shan; Zhang, Qiu-ling; Xu, Chang-lin; Liu, Chang-bai

2013-03-01

Induced pluripotent stem (iPS) cells were originally generated from mouse fibroblasts by enforced expression of Yamanaka factors (Oct3/4, Sox2, Klf4, and c-Myc). The technique was quickly reproduced with human fibroblasts or mesenchymal stem cells. Although having been showed therapeutic potential in animal models of sickle cell anemia and Parkinson's disease, iPS cells generated by viral methods do not suit all the clinical applications. Various non-viral methods have appeared in recent years for application of iPS cells in cell transplantation therapy. These methods mainly include DNA vector-based approaches, transfection of mRNA, and transduction of reprogramming proteins. This review summarized these non-viral methods and compare the advantages, disadvantages, efficiency, and safety of these methods.

Fast-acting valve and uses thereof

DOEpatents

Meyer, J.A.

1980-05-16

A very fast acting valve capable of producing a very well-defined plug of gas suitable for filling a theta pinch vacuum vessel is given. The valve requires no springs, instead being stopped mainly by a nonlinear force. Thus, the valve is not subject to bouncing; and the ratio of the size of the valve housing to the size of the valve stem is smaller than it would be if springs were needed to stop the valve stem. Furthermore, the valve can be used for thousands of valve firings with no apparent valve damage.

Martins Fork Lake Sedimentation Study. Hydraulic Model Investigation

DTIC Science & Technology

1988-09-01

30 per- cent of the 1.67 acre-ft/square mile, or 0.50 acre-ft/square mile was selected to represent the new expected sediment inflow rate (USAED...Cross Sec- tion Coordinates" (GEDA). The GEDA files were converted to HEC-6 format. Roughness 15. Manning’s n values were selected for each stem of...the network. The values selected are shown in Table 2. Table 2 * Manning’s n Values Network n Value Martins Fork main stem 0.040 Crane Creek 0.045 Board

Fast-acting valve and uses thereof

DOEpatents

Meyer, James A.

1982-01-01

A very fast acting valve capable of producing a very well-defined plug of gas suitable for filling a theta pinch vacuum vessel is given. The valve requires no springs, instead being stopped mainly by a nonlinear force. Thus, the valve is not subject to bouncing; and the ratio of the size of the valve housing to the size of the valve stem is smaller than it would be if springs were needed to stop the valve stem. Furthermore, the valve can be used for thousands of valve firings with no apparent valve damage.

Graft-versus-Leukemia Effect Following Hematopoietic Stem Cell Transplantation for Leukemia

PubMed Central

Dickinson, Anne M.; Norden, Jean; Li, Shuang; Hromadnikova, Ilona; Schmid, Christoph; Schmetzer, Helga; Jochem-Kolb, Hans

2017-01-01

The success of hematopoietic stem cell transplantation (HSCT) lies with the ability of the engrafting immune system to remove residual leukemia cells via a graft-versus-leukemia effect (GvL), caused either spontaneously post-HSCT or via donor lymphocyte infusion. GvL effects can also be initiated by allogenic mismatched natural killer cells, antigen-specific T cells, and activated dendritic cells of leukemic origin. The history and further application of this GvL effect and the main mechanisms will be discussed and reviewed in this chapter. PMID:28638379

[The embryonic stem cells research. Example of biotechnology progress under extra-scientific pressure].

PubMed

Gámez Escalona, José Antonio

2013-01-01

The possibility to isolate, cultivate, preserve, characterize and differentiate Human Embryonic Stem Cells (ES) discovered by James Thomson and his colleagues in 1998 was a milestone in the history of Stem Cell Research. Immediately after this discovery many speculations were made about the therapeutic possibilities of ES, motivated by ideological, political and economic aspects. The episode made clear the lack of scientific rationality and ethics when assessing realities as meaningful as those of human embryos obtained by in vitro fertilization techniques (IVF) or human eggs. Therapeutic Cloning as a promise to produce ″tailored″ Stem Cells reported by Hwang and his team in 2004, ended up being a scandal within the scientific community. The technical difficulties and ethical controversies that arose from obtaining ES were insurmountable. In 2010 only two clinical trials were reported using these cells. Those trials were abandoned in late 2011 arguing financial reasons. The discovery of Induced Pluripotent Stem Cell (iPS) in 2006 in mice and in 2007 in humans, represented the possibility of obtaining pluripotent stem cells without the need to destroy embryos. Today, the absence of clinical trials using ES, caused by financial difficulties as a result of its ineffectiveness, anticipates that the use of ES will be limited to certain experimental controls. Probably, the main contribution of Embryonic Stem Cells will be the understanding that biomedical research should follow an ethically and rationally based rigorous method that cannot be ignore.

Potential Use of Human Periapical Cyst-Mesenchymal Stem Cells (hPCy-MSCs) as a Novel Stem Cell Source for Regenerative Medicine Applications

PubMed Central

Tatullo, Marco; Codispoti, Bruna; Pacifici, Andrea; Palmieri, Francesca; Marrelli, Massimo; Pacifici, Luciano; Paduano, Francesco

2017-01-01

Mesenchymal stem cells (MSCs) are attracting growing interest by the scientific community due to their huge regenerative potential. Thus, the plasticity of MSCs strongly suggests the utilization of these cells for regenerative medicine applications. The main issue about the clinical use of MSCs is related to the complex way to obtain them from healthy tissues; this topic has encouraged scientists to search for novel and more advantageous sources of these cells in easily accessible tissues. The oral cavity hosts several cell populations expressing mesenchymal stem cell like-features, furthermore, the access to oral and dental tissues is simple and isolation of cells is very efficient. Thus, oral-derived stem cells are highly attractive for clinical purposes. In this context, human periapical cyst mesenchymal stem cells (hPCy-MSCs) exhibit characteristics similar to other dental-derived MSCs, including their extensive proliferative potential, cell surface marker profile and the ability to differentiate into various cell types such as osteoblasts, adipocytes and neurons. Importantly, hPCy-MSCs are easily collected from the surgically removed periapical cysts; this reusing of biological waste guarantees a smart source of stem cells without any impact on the surrounding healthy tissues. In this review, we report the most interesting research topics related to hPCy-MSCs with a newsworthy discussion about the future insights. This newly discovered cell population exhibits interesting and valuable potentialities that could be of high impact in the future regenerative medicine applications. PMID:29259970

Potential Use of Human Periapical Cyst-Mesenchymal Stem Cells (hPCy-MSCs) as a Novel Stem Cell Source for Regenerative Medicine Applications.

PubMed

Tatullo, Marco; Codispoti, Bruna; Pacifici, Andrea; Palmieri, Francesca; Marrelli, Massimo; Pacifici, Luciano; Paduano, Francesco

2017-01-01

Mesenchymal stem cells (MSCs) are attracting growing interest by the scientific community due to their huge regenerative potential. Thus, the plasticity of MSCs strongly suggests the utilization of these cells for regenerative medicine applications. The main issue about the clinical use of MSCs is related to the complex way to obtain them from healthy tissues; this topic has encouraged scientists to search for novel and more advantageous sources of these cells in easily accessible tissues. The oral cavity hosts several cell populations expressing mesenchymal stem cell like-features, furthermore, the access to oral and dental tissues is simple and isolation of cells is very efficient. Thus, oral-derived stem cells are highly attractive for clinical purposes. In this context, human periapical cyst mesenchymal stem cells (hPCy-MSCs) exhibit characteristics similar to other dental-derived MSCs, including their extensive proliferative potential, cell surface marker profile and the ability to differentiate into various cell types such as osteoblasts, adipocytes and neurons. Importantly, hPCy-MSCs are easily collected from the surgically removed periapical cysts; this reusing of biological waste guarantees a smart source of stem cells without any impact on the surrounding healthy tissues. In this review, we report the most interesting research topics related to hPCy-MSCs with a newsworthy discussion about the future insights. This newly discovered cell population exhibits interesting and valuable potentialities that could be of high impact in the future regenerative medicine applications.

Stem cells in animal asthma models: a systematic review.

PubMed

Srour, Nadim; Thébaud, Bernard

2014-12-01

Asthma control frequently falls short of the goals set in international guidelines. Treatment options for patients with poorly controlled asthma despite inhaled corticosteroids and long-acting β-agonists are limited, and new therapeutic options are needed. Stem cell therapy is promising for a variety of disorders but there has been no human clinical trial of stem cell therapy for asthma. We aimed to systematically review the literature regarding the potential benefits of stem cell therapy in animal models of asthma to determine whether a human trial is warranted. The MEDLINE and Embase databases were searched for original studies of stem cell therapy in animal asthma models. Nineteen studies were selected. They were found to be heterogeneous in their design. Mesenchymal stromal cells were used before sensitization with an allergen, before challenge with the allergen and after challenge, most frequently with ovalbumin, and mainly in BALB/c mice. Stem cell therapy resulted in a reduction of bronchoalveolar lavage fluid inflammation and eosinophilia as well as Th2 cytokines such as interleukin-4 and interleukin-5. Improvement in histopathology such as peribronchial and perivascular inflammation, epithelial thickness, goblet cell hyperplasia and smooth muscle layer thickening was universal. Several studies showed a reduction in airway hyper-responsiveness. Stem cell therapy decreases eosinophilic and Th2 inflammation and is effective in several phases of the allergic response in animal asthma models. Further study is warranted, up to human clinical trials. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

How to become a tree without wood--biomechanical analysis of the stem of Carica papaya L.

PubMed

Kempe, A; Lautenschläger, T; Lange, A; Neinhuis, C

2014-01-01

Carica papaya L. does not contain wood, according to the botanical definition of wood as lignified secondary xylem. Despite its parenchymatous secondary xylem, these plants are able to grow up to 10-m high. This is surprising, as wooden structural elements are the ubiquitous strategy for supporting height growth in plants. Proposed possible alternative principles to explain the compensation for lack of wood in C. papaya are turgor pressure of the parenchyma, lignified phloem fibres in the bark, or a combination of the two. Interestingly, lignified tissue comprises only 5-8% of the entire stem mass. Furthermore, the phloem fibres do not form a compact tube enclosing the xylem, but instead form a mesh tubular structure. To investigate the mechanism of papaya's unusually high mechanical strength, a set of mechanical measurements were undertaken on whole stems and tissue sections of secondary phloem and xylem. The structural Young's modulus of mature stems reached 2.5 GPa. Since this is low compared to woody plants, the flexural rigidity of papaya stem construction may mainly be based on a higher second moment of inertia. Additionally, stem turgor pressure was determined indirectly by immersing specimens in sucrose solutions of different osmolalities, followed by mechanical tests; turgor pressure was between 0.82 and 1.25 MPa, indicating that turgor is essential for flexural rigidity of the entire stem. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

Periodontal tissue engineering strategies based on nonoral stem cells.

PubMed

Requicha, João Filipe; Viegas, Carlos Alberto; Muñoz, Fernando; Reis, Rui Luís; Gomes, Manuela Estima

2014-01-01

Periodontal disease is an inflammatory disease which constitutes an important health problem in humans due to its enormous prevalence and life threatening implications on systemic health. Routine standard periodontal treatments include gingival flaps, root planning, application of growth/differentiation factors or filler materials and guided tissue regeneration. However, these treatments have come short on achieving regeneration ad integrum of the periodontium, mainly due to the presence of tissues from different embryonic origins and their complex interactions along the regenerative process. Tissue engineering (TE) aims to regenerate damaged tissue by providing the repair site with a suitable scaffold seeded with sufficient undifferentiated cells and, thus, constitutes a valuable alternative to current therapies for the treatment of periodontal defects. Stem cells from oral and dental origin are known to have potential to regenerate these tissues. Nevertheless, harvesting cells from these sites implies a significant local tissue morbidity and low cell yield, as compared to other anatomical sources of adult multipotent stem cells. This manuscript reviews studies describing the use of non-oral stem cells in tissue engineering strategies, highlighting the importance and potential of these alternative stem cells sources in the development of advanced therapies for periodontal regeneration. Copyright © 2013 Wiley Periodicals, Inc.

A Campus-Wide Study of STEM Courses: New Perspectives on Teaching Practices and Perceptions

PubMed Central

Vinson, Erin L.; Smith, Jeremy A.; Lewin, Justin D.; Stetzer, MacKenzie R.

2014-01-01

At the University of Maine, middle and high school science, technology, engineering, and mathematics (STEM) teachers observed 51 STEM courses across 13 different departments and collected information on the active-engagement nature of instruction. The results of these observations show that faculty members teaching STEM courses cannot simply be classified into two groups, traditional lecturers or instructors who teach in a highly interactive manner, but instead exhibit a continuum of instructional behaviors between these two classifications. In addition, the observation data reveal that student behavior differs greatly in classes with varied levels of lecture. Although faculty members who teach large-enrollment courses are more likely to lecture, we also identified instructors of several large courses using interactive teaching methods. Observed faculty members were also asked to complete a survey about how often they use specific teaching practices, and we find that faculty members are generally self-aware of their own practices. Taken together, these findings provide comprehensive information about the range of STEM teaching practices at a campus-wide level and how such information can be used to design targeted professional development for faculty. PMID:25452485

On the Progress of Scanning Transmission Electron Microscopy (STEM) Imaging in a Scanning Electron Microscope.

PubMed

Sun, Cheng; Müller, Erich; Meffert, Matthias; Gerthsen, Dagmar

2018-04-01

Transmission electron microscopy (TEM) with low-energy electrons has been recognized as an important addition to the family of electron microscopies as it may avoid knock-on damage and increase the contrast of weakly scattering objects. Scanning electron microscopes (SEMs) are well suited for low-energy electron microscopy with maximum electron energies of 30 keV, but they are mainly used for topography imaging of bulk samples. Implementation of a scanning transmission electron microscopy (STEM) detector and a charge-coupled-device camera for the acquisition of on-axis transmission electron diffraction (TED) patterns, in combination with recent resolution improvements, make SEMs highly interesting for structure analysis of some electron-transparent specimens which are traditionally investigated by TEM. A new aspect is correlative SEM, STEM, and TED imaging from the same specimen region in a SEM which leads to a wealth of information. Simultaneous image acquisition gives information on surface topography, inner structure including crystal defects and qualitative material contrast. Lattice-fringe resolution is obtained in bright-field STEM imaging. The benefits of correlative SEM/STEM/TED imaging in a SEM are exemplified by structure analyses from representative sample classes such as nanoparticulates and bulk materials.

Morphological description of limbal epithelium: searching for stem cells crypts in the dog, cat, pig, cow, sheep and horse.

PubMed

Patruno, M; Perazzi, A; Martinello, T; Blaseotto, A; Di Iorio, E; Iacopetti, I

2017-06-01

The cornea provides protection and transparency to the eye, allowing an optimal sharpness view. In some pathological conditions the cornea is able to regenerate thanks to the presence of a stem cells reservoir present at the level of the transition area between cornea and sclera (limbus). Corneal cell therapies in Veterinary Medicine are really limited due to the lacking of knowledge about the anatomy of the limbal area, the putative presence of stem cells and their identification in domestic species. The aim of this study was to provide an overview of the main distinctive structural features of the sclero-corneal junction and conjunctival-corneal junction areas in some species of veterinary importance, using optic microscope observations of histological sections. The resulting data were compared with cornea from humans adapting protocols already used to identify stem cells by means of a specific cellular marker. We tested the expression of ΔNp63α isoform in the cornea basal cells, trying to correlate the distribution profile with areas of highly proliferative turnover. The results obtained from this study represent a first step towards the identification of a corneal stem cells reservoir in different animals.

Growth Factors and Stem Cells for the Management of Anterior Cruciate Ligament Tears

PubMed Central

Rizzello, Giacomo; Longo, Umile Giuseppe; Petrillo, Stefano; Lamberti, Alfredo; Khan, Wasim Sardar; Maffulli, Nicola; Denaro, Vincenzo

2012-01-01

The anterior cruciate ligament (ACL) is fundamental for the knee joint stability. ACL tears are frequent, especially during sport activities, occurring mainly in young and active patients. Nowadays, the gold standard for the management of ACL tears remains the surgical reconstruction with autografts or allografts. New strategies are being developed to resolve the problems of ligament grafting and promote a physiological healing process of ligamentous tissue without requiring surgical reconstruction. Moreover, these strategies can be applicable in association surgical reconstruction and may be useful to promote and accelerate the healing process. The use of growth factors and stem cells seems to offer a new and fascinating solution for the management of ACL tears. The injection of stem cell and/or growth factors in the site of ligamentous injury can potentially enhance the repair process of the physiological tissue. These procedures are still at their infancy, and more in vivo and in vitro studies are required to clarify the molecular pathways and effectiveness of growth factors and stem cells therapy for the management of ACL tears. This review aims to summarize the current knowledge in the field of growth factors and stem cells for the management of ACL tears. PMID:23248722

Assessment of ecological conditions and potential effects of water produced from coalbed natural gas development on biological communities in streams of the Powder River structural basin, Wyoming and Montana, 2005-08

USGS Publications Warehouse

Peterson, David A.; Clark, Melanie L.; Foster, Katharine; Wright, Peter R.; Boughton, Gregory K.

2010-01-01

Ongoing development of coalbed natural gas in the Powder River structural basin in Wyoming and Montana led to formation of an interagency task group to address concerns about the effects of the resulting production water on biological communities in streams of the area. The interagency task group developed a monitoring plan and conducted sampling of macroinvertebrate, algal, and fish communities at 47 sites during 2005-08 to document current ecological conditions and determine existing and potential effects of water produced from coalbed natural gas development on biological communities. Macroinvertebrate, algal, and fish community composition varied between drainage basins, among sites within drainage basins, and by year. Macroinvertebrate communities of the main-stem Tongue River were characterized by higher taxa richness and higher abundance of Ephemeroptera, for example, compared to macroinvertebrate communities in plains tributaries of the Tongue River and the main-stem Powder River. Fish communities of the Tongue River were characterized by higher taxa richness and abundance of introduced species compared to the Powder River where native species were dominant. Macroinvertebrate community metric values from sites in the middle reach of the main-stem Powder River, from below Willow Creek to below Crazy Woman Creek, differed from metric values in the upper and lower reaches of the Powder River. Metrics indicative of communitywide differences included measures of taxa richness, relative abundance, feeding mode, and tolerance. Some of the variation in the macroinvertebrate communities could be explained by variation in environmental variables, including physical (turbidity, embeddedness, bed substrate size, and streamflow) and chemical (alkalinity and specific conductance) variables. Of these environmental variables, alkalinity was the best indicator of coalbed natural gas development because of the sodiumbicarbonate signature of the production water. Algal samples from the main-stem Powder River generally confirmed the pattern observed in the macroinvertebrate communities. Algal communities at sites in the middle reach of the Powder River commonly were characterized by dominance by a single taxon and by low biovolume of algae compared to other sites. In contrast to the macroinvertebrate and algal communities, species richness of fish communities was highest in the middle reach of the Powder River. Although a few significant differences in fish metrics were determined along the main-stem Powder River, the differences did not correspond to the pattern observed for the macroinvertebrate and algae communities. Differences in biological communities were noted between years, potentially due to the effects of drought. Macroinvertebrate community metrics, such as Diptera taxa richness, were significantly different in the severe drought year of 2006 from metric values in 2005 and 2007-08. Waterquality data collected during the study indicated that, with few exceptions, water-quality constituents generally did not exceed State or Federal acute and chronic criteria for the protection of aquatic life.

KUSPACE: Embedding Science Technology and Mathematics Ambassador Activities in the Undergradiuate Engineering Curriculum

NASA Astrophysics Data System (ADS)

Welch, C.; Osborne, B.

The UK national STEM Ambassadors programme provides inspiring role models for school students in science, technology, engineering, mathematics (STEM) subjects. STEMNET, the national body responsible for STEM Ambassa- dors aims to provide more than 27,000 STEM Ambassadors nationwide by the end of 2011. This paper reports on a project at Kingston University to embed STEM Ambassador training and activity in Year 2 of the undergraduate Aerospace Engineering, Astronautics and Space Technology degree. The project, known as KUSPACE (Kingston University Students Providing Amazing Classroom Experiences), was conceived to develop students' communication, planning and presentation skills and build links between different cohort years, while providing a valuable contribution to local primary schools' STEM programmes and simultaneously raising the public engagement profile of the university. This paper describes the pedagogical conception of the KUSPACE, its implementation in the curriculum, the delivery of it in the university and schools and its effect on the undergraduate students, as well as identifying good practice and drawing attention to lessons learned.STEMNET (www.stemnet.org) is the UK's Science, Technol- ogy, Engineering and Mathematics Network. Working with a broad range of UK partners and funded by the UK govern- ment's Department for Business Innovation and Skills, STEMNET plays a significant role in ensuring that five to nineteen year olds and their teachers can experience a wide range of activities and schemes which enhance and enrich the school curriculum [1]. Covering all aspects of Science, Tech- nology, Engineering and Maths (STEM), these activities and schemes are designed both to increase STEM awareness and literacy in the young people and also to encourage more of them to undertake post-16 STEM qualifications and associated careers [2]. STEMNET operates through forty-five local con- tract holders around the UK which help the network deliver its programmes to schools and organisations in their particular areas, mainly through the STEM Ambassador Programme (see below) and the Schools STEM Advisory Network.In support of its vision - `To increase young people's choice and chances through science, technology, engineering, and mathematics ' - STEMNET seeks to be a recognised leader in enabling all young people to achieve their potential in STEM by:

Better early functional outcome after short stem total hip arthroplasty? A prospective blinded randomised controlled multicentre trial comparing the Collum Femoris Preserving stem with a Zweymuller straight cementless stem total hip replacement for the treatment of primary osteoarthritis of the hip

PubMed Central

van Oldenrijk, Jakob; Scholtes, Vanessa A B; van Beers, Loes W A H; Geerdink, Carel H; Niers, Bob B A M; Runne, Wouter; Bhandari, Mohit; Poolman, Rudolf W

2017-01-01

Objectives Primary aim was to compare the functional results at 3 months and 2 years between short and conventional cementless stem total hip arthroplasty (THA). Secondary aim was to determine the feasibility of a double-blind implant-related trial. Design A prospective blinded randomised controlled multicentre trial in patients with osteoarthritis of the hip. All patients, research assistants, clinical assessors, investigators and data analysts were blinded to the type of prosthesis. Population: 150 patients between 18 and 70 years with osteoarthritis of the hip, 75 in the short stem and 75 in the conventional stem group. Mean age: 60 years (SD 7). Interventions: the Collum Femoris Preserving short stem versus the Zweymuller Alloclassic conventional stem. Main outcome measures The Dutch version of the Hip Disability and Osteoarthritis Outcome Score (HOOS). Secondary outcomes measures: Harris Hip Score, the Physical Component Scale of the SF12, the Timed Up and Go test, Pain and the EQ-5D. Feasibility outcomes: continued blinding, protocol adherence and follow-up success rate. Results No significant difference between the two groups. Mean HOOS total score in the short stem group increased 32.7 points from 36.6 (95% CI 32.9 to 40.2) preoperatively to 69.3 (95% CI 66.4 to 72.1) at 3 months follow-up. Mean HOOS total score in the conventional straight stem group increased 36.3 points from 37.1 (95% CI 33.9 to 40.3) preoperatively to 73.4 (95% CI 70.3 to 76.4) at 3 months follow-up. 91.2% of patients remained blinded at 2 years follow-up. Both protocol adherence and follow-up success rate were 98%. Conclusions Functional result at 3 months and 2 years after short stem THA is not superior to conventional cementless THA. There were more perioperative and postoperative complications in the short stem group. Direct comparison of two hip implants in a double-blinded randomised controlled trial is feasible. Trial registration number NTR1560. PMID:29042371

Developmental patterns of jicama (Pachyrhizus erosus (L.) Urban) plant and the chemical constituents of roots grown in Sonora, Mexico.

PubMed

Fernandez, M V; Warid, W A; Loaiza, J M; Montiel, A

1997-01-01

The developmental pattern of jicama (Pachyrhizus erosus (L.) Urban) was studied by sampling plants aged 20 to 36 weeks at weekly intervals. There was an increase in all characteristics of foliage: fresh and dry weight, number of leaves per plant, main stem length, number of leaves, nodes and internodes of the main stem; and in all root characteristics: fresh and dry weight, diameter and length. The chemical analysis was determined for roots at different plant ages. The range values for dry matter were 16.19-22.28%, protein 1.11-1.62%, fat 0.553-0.867%, crude fiber 0.3048-0.3943%, and ash 0.669-1.089%. The chemical constituents fluctuated with age but without specific trends. These values are considered the first record of roots produced by plants grown in Mexico.

Assessment of selected water-quality data collected in the lower Red River (main stem) basin, Texas, 1997-98

USGS Publications Warehouse

Baldys, Stanley; Hamilton, Danna K.

2003-01-01

The Texas part of the Red River Basin has been divided into five reaches or subbasins (fig. 1) to facilitate improved planning, monitoring, geographical analysis, and dissemination of information. The U.S. Geological Survey (USGS), in cooperation with the Red River Authority of Texas, is studying the five subbasins, each for a period of about 1 year. Baldys and Phillips (1998) discuss various components and the associated scope of study of each of the five reaches. Data from the first reach studied—reach 2, the Wichita River Basin—were presented in a fact sheet by Baldys and Phillips (2000). This fact sheet presents an assessment of data collected at 11 sites during 1997–98 for reach 1—the lower Red River (main stem) Basin from the confluence of Cache Creek downstream to the Texas-Arkansas State Line (fig. 1).

Localized cooling of stems induces latewood formation and cambial dormancy during seasons of active cambium in conifers

PubMed Central

Begum, Shahanara; Kudo, Kayo; Matsuoka, Yugo; Nakaba, Satoshi; Yamagishi, Yusuke; Nabeshima, Eri; Rahman, Md Hasnat; Nugroho, Widyanto Dwi; Oribe, Yuichiro; Jin, Hyun-O; Funada, Ryo

2016-01-01

Background and Aims In temperate regions, trees undergo annual cycles of cambial growth, with periods of cambial activity and dormancy. Environmental factors might regulate the cambial growth, as well as the development of cambial derivatives. We investigated the effects of low temperature by localized cooling on cambial activity and latewood formation in two conifers, Chamaecyparis obtusa and Cryptomeria japonica. Methods A plastic rubber tube that contained cooled water was wrapped around a 30-cm-wide portion of the main stem of Chamaecyparis obtusa and Cryptomeria japonica trees during seasons of active cambium. Small blocks were collected from both cooled and non-cooled control portions of the stems for sequential observations of cambial activity and for anatomical measurements of cell morphology by light microscopy and image analysis. Key Results The effect of localized cooling was first observed on differentiating tracheids. Tracheids narrow in diameter and with significantly decreased cambial activity were evident 5 weeks after the start of cooling in these stems. Eight weeks after the start of cooling, tracheids with clearly diminished diameters and thickened cell walls were observed in these stems. Thus, localized low temperature induced narrow diameters and obvious thickening of secondary cell walls of tracheids, which were identified as latewood tracheids. Two months after the cessation of cooling, a false annual ring was observed and cambium became active again and produced new tracheids. In Cryptomeria japonica, cambial activity ceased earlier in locally cooled portions of stems than in non-cooled stems, indicating that the cambium had entered dormancy sooner in the cooled stems. Conclusions Artificial cooling of stems induced latewood formation and cessation of cambial activity, indicating that cambium and its derivatives can respond directly to changes in temperature. A decrease in the temperature of the stem is a critical factor in the control of cambial activity and xylem differentiation in trees. PMID:26703452

Detection of Single Tree Stems in Forested Areas from High Density ALS Point Clouds Using 3d Shape Descriptors

NASA Astrophysics Data System (ADS)

Amiri, N.; Polewski, P.; Yao, W.; Krzystek, P.; Skidmore, A. K.

2017-09-01

Airborne Laser Scanning (ALS) is a widespread method for forest mapping and management purposes. While common ALS techniques provide valuable information about the forest canopy and intermediate layers, the point density near the ground may be poor due to dense overstory conditions. The current study highlights a new method for detecting stems of single trees in 3D point clouds obtained from high density ALS with a density of 300 points/m2. Compared to standard ALS data, due to lower flight height (150-200 m) this elevated point density leads to more laser reflections from tree stems. In this work, we propose a three-tiered method which works on the point, segment and object levels. First, for each point we calculate the likelihood that it belongs to a tree stem, derived from the radiometric and geometric features of its neighboring points. In the next step, we construct short stem segments based on high-probability stem points, and classify the segments by considering the distribution of points around them as well as their spatial orientation, which encodes the prior knowledge that trees are mainly vertically aligned due to gravity. Finally, we apply hierarchical clustering on the positively classified segments to obtain point sets corresponding to single stems, and perform ℓ1-based orthogonal distance regression to robustly fit lines through each stem point set. The ℓ1-based method is less sensitive to outliers compared to the least square approaches. From the fitted lines, the planimetric tree positions can then be derived. Experiments were performed on two plots from the Hochficht forest in Oberösterreich region located in Austria.We marked a total of 196 reference stems in the point clouds of both plots by visual interpretation. The evaluation of the automatically detected stems showed a classification precision of 0.86 and 0.85, respectively for Plot 1 and 2, with recall values of 0.7 and 0.67.

Localized cooling of stems induces latewood formation and cambial dormancy during seasons of active cambium in conifers.

PubMed

Begum, Shahanara; Kudo, Kayo; Matsuoka, Yugo; Nakaba, Satoshi; Yamagishi, Yusuke; Nabeshima, Eri; Rahman, Md Hasnat; Nugroho, Widyanto Dwi; Oribe, Yuichiro; Jin, Hyun-O; Funada, Ryo

2016-03-01

In temperate regions, trees undergo annual cycles of cambial growth, with periods of cambial activity and dormancy. Environmental factors might regulate the cambial growth, as well as the development of cambial derivatives. We investigated the effects of low temperature by localized cooling on cambial activity and latewood formation in two conifers, Chamaecyparis obtusa and Cryptomeria japonica. A plastic rubber tube that contained cooled water was wrapped around a 30-cm-wide portion of the main stem of Chamaecyparis obtusa and Cryptomeria japonica trees during seasons of active cambium. Small blocks were collected from both cooled and non-cooled control portions of the stems for sequential observations of cambial activity and for anatomical measurements of cell morphology by light microscopy and image analysis. The effect of localized cooling was first observed on differentiating tracheids. Tracheids narrow in diameter and with significantly decreased cambial activity were evident 5 weeks after the start of cooling in these stems. Eight weeks after the start of cooling, tracheids with clearly diminished diameters and thickened cell walls were observed in these stems. Thus, localized low temperature induced narrow diameters and obvious thickening of secondary cell walls of tracheids, which were identified as latewood tracheids. Two months after the cessation of cooling, a false annual ring was observed and cambium became active again and produced new tracheids. In Cryptomeria japonica, cambial activity ceased earlier in locally cooled portions of stems than in non-cooled stems, indicating that the cambium had entered dormancy sooner in the cooled stems. Artificial cooling of stems induced latewood formation and cessation of cambial activity, indicating that cambium and its derivatives can respond directly to changes in temperature. A decrease in the temperature of the stem is a critical factor in the control of cambial activity and xylem differentiation in trees. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Stemming Malay Text and Its Application in Automatic Text Categorization

NASA Astrophysics Data System (ADS)

Yasukawa, Michiko; Lim, Hui Tian; Yokoo, Hidetoshi

In Malay language, there are no conjugations and declensions and affixes have important grammatical functions. In Malay, the same word may function as a noun, an adjective, an adverb, or, a verb, depending on its position in the sentence. Although extensively simple root words are used in informal conversations, it is essential to use the precise words in formal speech or written texts. In Malay, to make sentences clear, derivative words are used. Derivation is achieved mainly by the use of affixes. There are approximately a hundred possible derivative forms of a root word in written language of the educated Malay. Therefore, the composition of Malay words may be complicated. Although there are several types of stemming algorithms available for text processing in English and some other languages, they cannot be used to overcome the difficulties in Malay word stemming. Stemming is the process of reducing various words to their root forms in order to improve the effectiveness of text processing in information systems. It is essential to avoid both over-stemming and under-stemming errors. We have developed a new Malay stemmer (stemming algorithm) for removing inflectional and derivational affixes. Our stemmer uses a set of affix rules and two types of dictionaries: a root-word dictionary and a derivative-word dictionary. The use of set of rules is aimed at reducing the occurrence of under-stemming errors, while that of the dictionaries is believed to reduce the occurrence of over-stemming errors. We performed an experiment to evaluate the application of our stemmer in text mining software. For the experiment, text data used were actual web pages collected from the World Wide Web to demonstrate the effectiveness of our Malay stemming algorithm. The experimental results showed that our stemmer can effectively increase the precision of the extracted Boolean expressions for text categorization.

Productive mRNA stem loop-mediated transcriptional slippage: Crucial features in common with intrinsic terminators.

PubMed

Penno, Christophe; Sharma, Virag; Coakley, Arthur; O'Connell Motherway, Mary; van Sinderen, Douwe; Lubkowska, Lucyna; Kireeva, Maria L; Kashlev, Mikhail; Baranov, Pavel V; Atkins, John F

2015-04-21

Escherichia coli and yeast DNA-dependent RNA polymerases are shown to mediate efficient nascent transcript stem loop formation-dependent RNA-DNA hybrid realignment. The realignment was discovered on the heteropolymeric sequence T5C5 and yields transcripts lacking a C residue within a corresponding U5C4. The sequence studied is derived from a Roseiflexus insertion sequence (IS) element where the resulting transcriptional slippage is required for transposase synthesis. The stability of the RNA structure, the proximity of the stem loop to the slippage site, the length and composition of the slippage site motif, and the identity of its 3' adjacent nucleotides (nt) are crucial for transcripts lacking a single C. In many respects, the RNA structure requirements for this slippage resemble those for hairpin-dependent transcription termination. In a purified in vitro system, the slippage efficiency ranges from 5% to 75% depending on the concentration ratios of the nucleotides specified by the slippage sequence and the 3' nt context. The only previous proposal of stem loop mediated slippage, which was in Ebola virus expression, was based on incorrect data interpretation. We propose a mechanical slippage model involving the RNAP translocation state as the main motor in slippage directionality and efficiency. It is distinct from previously described models, including the one proposed for paramyxovirus, where following random movement efficiency is mainly dependent on the stability of the new realigned hybrid. In broadening the scope for utilization of transcription slippage for gene expression, the stimulatory structure provides parallels with programmed ribosomal frameshifting at the translation level.