992 resultados para Nushagak, Alaska


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Many life-history traits are expressed interactively in life, but to a varying extent on different occasions. Changes in trait expression can be accounted for by differences in the quality of the environment ('environmental constraint' hypothesis) or by strategic adjustments, if the relative contribution of the trait to fitness varies with time ('strategic allocation' hypothesis). In birds, egg production is lower in replacement clutches than in first clutches, but it is unknown whether this reduction results from an environmental constraint (e.g. food being less available at the time when the replacement clutch is produced) or from a strategic allocation of resources between the two breeding attempts. To distinguish between these two hypotheses, we performed an experiment with black-legged kittiwakes (Rissa tridactyla). Pairs were either food-supplemented or not before the first clutch was laid onwards and we induced them to produce a replacement clutch by removing eggs once when the first clutch was complete. As predicted by the 'strategic allocation' hypothesis, egg production of food-supplemented and non-food-supplemented birds decreased between first and replacement clutches. This suggests that kittiwakes strategically reduce investment in egg production for their replacement clutches compared to first clutches.

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In 1875, 7 years prior to the description of the Koch bacillus, Klebs visualized the first Streptococcus pneumoniae in a pleural fluid. Since then, this organism has played a determinant role in biomedical science. From a biological point of view, it was largely implicated in the development of passive and active immunization by serotherapy and vaccination, respectively. Genetic transformation was also first observed in S. pneumoniae, leading to the discovery of DNA. From a clinical point of view, S. pneumoniae is still today a prime cause of otitis media in children and of pneumonia in all age groups, as well as a predominant cause of meningitis and bacteremia. In adults, bacteremia is still entailed with a mortality of over 25%. Although S. pneumoniae remained very sensitive to penicillin for many years, penicillin-resistance has emerged and increased dramatically over the last 15 years. During this period of time, the frequency of penicillin-resistant isolates has increased from < or = 1% to frequencies varying from 20 to 60% in geographic areas as diverse as South Africa, Spain, France, Hungary, Iceland, Alaska, and numerous regions of the United States and South America. In Switzerland, the current frequency of penicillin-resistant pneumococci ranges between 5 and > or = 10%. The increase in penicillin-resistant pneumococci correlates with the intensive use of beta-lactam antibiotics. The mechanism of resistance is not due to bacterial production of penicillinase, but to an alteration of the bacterial target of penicillin, the so-called penicillin-binding proteins. Resistance is subdivided into (i) inter mediate level resistance (minimal inhibitory concentration [MIC] of penicillin of 0.1-1 mg/L) and (ii) high level resistance (MCI > or = 2 mg/L). The clinical significance of intermediate resistance remains poorly defined. On the other hand, highly resistant strains were responsible for numerous therapeutical failures, especially in cases of meningitis. Antibiotics recommended against penicillin-resistant pneumococci include cefotaxime, ceftriaxone, imipenem and in some instances vancomycin. However, penicillin-resistant pneumococci tend to present cross-resistances to all the antibotics of the beta-lactam family and could even become resistant to the last resort drugs mentioned above. Thus, in conclusion, the explosion of resistance to penicillin in pneumococci is a ubiquitous phenomenon which must be fought against by (i) a strict utilization of antibiotics, (ii) the practice of microbiological sampling of infected foci before treatment, (iii) the systematic surveillance of resistance profiles of pneumococci against antibiotics and (iv) the adequate vaccination of populations at risk.

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The State of Iowa and the Hiring Practices Working Group commissioned this review of the State’s hiring practices in response to recent concerns about these practices involving racial discrimination claims against the Departments of Human Services, Transportation, and Iowa Workforce Development. The State of Iowa should be commended for undertaking this review. The State has a longstanding Affirmative Action Program and commitment to diversity – they instituted their Affirmative Action Program in 1973, and continue their commitment to its success by making the changes necessary to ensure the program is viable and sustainable. Iowa Department of Administrative Services In July 2003, the State created the Iowa Department of Administrative Services (DAS) as a way to manage and coordinate the major resources of state government. DAS provides human resource services through an entrepreneurial management model. Entrepreneurial management is a customer-focused approach to delivering services. The customer departments have input about what services and products they want from DAS and in turn DAS is funded by the customer departments through purchases of DAS services and products. DAS looks to offer new and additional services (for example recruitment support and coordination) to various customers on a fee-for-service basis. A customer council is charged with approving the DAS business plan, establishing the rate for services, and reviewing service delivery and complaints. Under this entrepreneurial model, human resource services are provided by DAS-HRE (Human Resources Enterprise) central staff, 12 DAS-HRE Personnel Officers located at the customer departments, and customer agency staff. The majority of the recruitment and hiring functions are done by the customer (hiring) departments and their staff. Applications for employment are submitted using the BrassRing system with applicants being qualified by DAS-HRE employees. Since the creation of Human Resources Enterprise, DAS-HRE has strived to provide human resource tools to the departments. The Screening Manual and the Supervisor’s Manual are just two examples of the resources created for the hiring departments. They also provide Supervisor Training for newly appointed supervisors. Larger departments have dedicated staff assigned to human resource activities. The staff at the departmental level may or may not have a human resources background. Iowa Population and Workforce The 2000 U.S. Census indicated that Iowa’s population was 2,926,324. According to this census, 92.6 percent of Iowa’s population identified their race as white (alone). The nonwhite alone or minority population (including Black or African American, Asian, Native Hawaiian or Pacific Islander, Hispanic or Latino, American Indian or Alaska Native, two or more races, or some other race) was 7.4 percent.

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Pavement marking technology is a continually evolving subject. There are numerous types of materials used in the field today, including (but not limited to) paint, epoxy, tape, and thermoplastic. Each material has its own set of unique characteristics related to durability, retro reflectivity, installation cost, and life-cycle cost. The Iowa Highway Research Board was interested in investigating the possibility of developing an ongoing program to evaluate the various products used in pavement marking. This potential program would maintain a database of performance and cost information to assist state and local agencies in determining which materials and placement methods are most appropriate for their use. The Center for Transportation Research and Education at Iowa State University has completed Phase I of this research: to identify the current practice and experiences from around the United States to recommend a further course of action for the State of Iowa. There has been a significant amount of research completed in the last several years. Research from Michigan, Pennsylvania, South Dakota, Ohio, and Alaska all had some common findings: white markings are more retro reflective than yellow markings; paint is by-and-large the least expensive material; paint tends to degrade faster than other materials; thermoplastic and tapes had higher retro reflective characteristics. Perhaps the most significant program going on in the area of pavement markings is the National Transportation Product Evaluation Program (NTPEP). This is an ongoing research program jointly conducted by the American Association of State Highway and Transportation Officials and its member states. Field and lab tests on numerous types of pavement marking materials are being conducted at sites representing four climatological areas. These results are published periodically for use by any jurisdiction interested in pavement marking materials performance.At this time, it is recommended that the State of Iowa not embark on a test deck evaluation program. Instead, close attention should be paid to the ongoing evaluations of the NTPEP program. Materials that fare well on the NTPEP test de cks should be considered for further field studies in Iowa.

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Pavement marking technology is a continually evolving subject. There are numerous types of materials used in the field today, including (but not limited to) paint, epoxy, tape, and thermoplastic. Each material has its own set of unique characteristics related to durability, retroreflectivity, installation cost, and life-cycle cost. The Iowa Highway Research Board was interested in investigating the possibility of developing an ongoing program to evaluate the various products used in pavement marking. This potential program would maintain a database of performance and cost information to assist state and local agencies in determining which materials and placement methods are most appropriate for their use. The Center for Transportation Research and Education at Iowa State University has completed Phase I of this research: to identify the current practice and experiences from around the United States to recommend a further course of action for the State of Iowa. There has been a significant amount of research completed in the last several years. Research from Michigan, Pennsylvania, South Dakota, Ohio, and Alaska all had some common findings: white markings are more retroreflective than yellow markings; paint is by-and-large the least expensive material; paint tends to degrade faster than other materials; thermoplastic and tapes had higher retroreflective characteristics. Perhaps the most significant program going on in the area of pavement markings is the National Transportation Product Evaluation Program (NTPEP). This is an ongoing research program jointly conducted by the American Association of State Highway and Transportation Officials and its member states. Field and lab tests on numerous types of pavement marking materials are being conducted at sites representing four climatological areas. These results are published periodically for use by any jurisdiction interested in pavement marking materials performance. At this time, it is recommended that the State of Iowa not embark on a test deck evaluation program. Instead, close attention should be paid to the ongoing evaluations of the NTPEP program. Materials that fare well on the NTPEP test de cks should be considered for further field studies in Iowa.

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This report synthesizes the safety corridor programs of 13 states that currently have some type of program: Alaska, California, Florida, Kentucky, Minnesota, New Jersey, New Mexico, New York, Ohio, Oregon, Pennsylvania, Virginia, and Washington. This synthesis can help Midwestern states implement their own safety corridor programs and select pilot corridors or enhance existing corridors. Survey and interview information about the states’ programs was gathered from members of each state department of transportation (DOT) and Federal Highway Administration (FHWA) division office. Topics discussed included definitions of a safety corridor; length and number of corridors in the program; criteria for selection of a corridor; measures of effectiveness of an implemented safety corridor; organizational structure of the program; funding and legislation issues; and engineering, education, enforcement, and emergency medical service strategies. Safety corridor programs with successful results were then examined in more detail, and field visits were made to Kansas, Oregon, Pennsylvania, and Washington for first-hand observations. With the survey and field visit information, several characteristics of successful safety corridor programs were identified, including multidisciplinary (3E and 4E) efforts; selection, evaluation, and decommissioning strategies; organization structure, champions, and funding; task forces and Corridor Safety Action Plans; road safety audits; and legislation and other safety issues. Based on the synthesis, the report makes recommendations for establishing and maintaining a successful safety corridor program.

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Crystallisation of hydrous mafic magmas at high pressure is a subject of numerous petrologic and experimental studies since the last century and is mainly related to the process of continental crust formation and the possible link between mantle derived melts and low pressure granitoids. Albeit the sequence of crystallization is well constrained by experimental studies, the origin of exposed lower crustal rocks exposed on the earth surface is controversial. Ones line of argument is favouring high pressure crystallization of dry or wet mafic magmas, whereas others invoke partial melting of pre-existing crust. Therefore studies involving field, textural and chemical observations of exposed lower crust such as in Kohistan (Pakistan) or Talkeetna (Alaska) are crucial to understand the continental crust formation processes via arc magmatism. Epidote-bearing gabbros are very sparse and always associated with the deep part of continental crust (>30 km) as in the Kohistan Arc Complex (Pakistan) or in the Chelan Complex (western U.S.). Magmatic epidote is restricted to a small temperature interval above the water-saturated solidus of MORB and represent the last crystallizing liquids in lower crustal regions. However, epidote and melt stability at lower crustal pressures are not clearly established.¦The Chelan complex (western U.S.) at the base of the Cascadian Arc is composed mainly by peraluminous tonalité associated with gabbroic and ultramafic rocks and was traditionally interpreted as a migmatitic terrain. However field, chemical and mineralogical observations rather suggest a magmatic origin and point to a protracted crystallization at intermediate to high pressure ~ 1.0 GPa dominated by amphibole fractionation and followed by isobaric cooling down to 650°C. Crystal fractionation modelling using whole rock composition and field constraints is able to generate peraluminous tonalité. The modelled crystallisation sequence and the volume proportions are in agreement with experimental studies performed at these pressures. The Chelan complex was thus not formed during a partial melting event, but represent the sequence of crystallisation occurring at the base of the crust. Massive fractionation of hornblende is able to generate peraluminous tonalité without significant assimilation of crustal rock.¦Similarly to the Chelan complex, the base of the Kohistan arc is composed of cumulates derived by high pressure crystallization of hydrous magma. In garnet gabbros, epidote occurs as magmatic phase, crystallising from hydrous interstitial melt trapped between grain boundaries at lower crustal pressures (Ρ ~ 1.2 GPa) for temperature of (650-700 °C). Trace and REE signature in epidote indicate that epidote was formed through peritectic reaction involving garnet, clinopyroxene and plagioclase. At the beginning of the crystallisation epidote signature is dominated by REE content in the melt, whereas at the end the signature is dominated by reacting phases. Melt in equilibrium with epidote inferred from the partition coefficients available is similar to intrusive tonalité up the section indicating that hydrous melt was extracted from the garnet gabbros. In some gabbros epidote shows single homogeneous compositions, while in others coexisting epidote have different compositions indicating the presence of solvi along the Al-Fe3+ join. The overgowths are only observed in presence of paragonite in the assemblage, suggesting high water content. At high water content, the hydrous solidus is shift to lower temperature and probably intersects the solvi observed along the Al-Fe3+ join. Therefore, several compositions of epidote is stable at high water content.¦-¦La composition chimique de la croûte continentale est considérée comme similaire à celle du magmatisme calco-alcalin de marge continentale active (enrichissement en éléments mobiles dans les fluides, anomalies négatives en Nb, Ta et éléments à haut potentiel électronique, etc...). Cependant la nature andésitique de la croûte continentale (Si02 > 60 wt%), résultant des nombreuses intrusions de granitoïdes dans la croûte supérieure, est sujette à polémique et le lien entre les magmas dérivés du manteau et les roches évoluées de faible profondeur n'est pas clairement établi (fusion partielle de croûte basaltique, cristallisation fractionnée à haute pression, etc...).¦Les affleurements de croûte profonde sont rares mais précieux, car ils permettent d'observer les phénomènes se passant à grande profondeur. Le complexe de Chelan (Washington Cascades) en est un exemple. Formé à environ 30 km de profondeur, il est composé de roches gabbroïques et ultramafiques, ainsi que de tonalités, qui furent souvent interprétés comme le produit de la fusion partielle de la croûte. Cependant, les relations de terrain, la chimie des éléments majeurs et des éléments traces sont cohérentes avec l'évolution d'un complexe magmatique mafique dans la croûte profonde ou moyenne ( 1.0 GPa), dominée par le fractionnement de l'amphibole. Après son emplacement, le complexe a subi un refroidissement isobare jusqu'à des températures de l'ordre de 650 °C, déduit de la composition chimique des minéraux. Un bilan de masse contraint pax les observations de terrain permet de calculer la séquence et les volumes de fractionnement. Les faciès évolués légèrement hyperalumineux observés sur le terrain peuvent être générés par la cristallisation de 3 % de websterite à olivine, 12 % d'hornblendite à pyroxène 33 % d'hornblendite, 19 % de gabbros, 15 % de diorite et 2 % de tonalité. Nous montrons ainsi qu'une série de fractionnement contrôlée par l'amphibole permet de générer des tonalités sans assimilation de matériel crustal et l'exemple de Chelan illustre la viabilité de ce processus dans la formation de croûte continentale.¦Les réactions proches du solidus saturé en H20 dans les systèmes basaltiques à des pressions élevées restent énigmatiques. Diverses expériences tendent à montrer que l'épidote est stable dans ces conditions, mais rarement observée (décrite ?) comme phase primaire dans les systèmes naturels. Les épidotes trouvées dans les gabbros de Jijal (nord-Pakistan) montrent des textures de type .magmatique telles qu'observées dans les roches évoluées. Le contenu en terres rares de ces épidotes est très variable allant de signatures enrichies en terres rares légères impliquant la présence de liquide interstitiel à des signatures complètement déprimées en ces mêmes éléments, évoquant une cristallisation en coexistence avec du grenat. Ces diverses signatures reflètent un chemin de cristallisation en présence de liquide interstitiel et enregistrent des réactions péritectiques impliquant grenat, clinopyroxene et plagioclase à des pressions de ~ 1.2 GPa pour des températures de 650-700 °C. Cependant dans quelques échantillons deux ou trois compositions d'épidotes coexistent démontrant la présence de lacunes d'immiscibilité le long de la solution solide épidote-clinozoïsite. La forte teneur en H20 du liquide magmatique est certainement à l'origine de la coexistence de deux compositions distinctes.

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In 1875, 7 years prior to the description of the Koch bacillus, Klebs visualized the first Streptococcus pneumoniae in pleural fluid. Since then, this organism has played a decisive role in biomedical science. From a biological point of view, it was extensively involved in the development of passive and active immunization by serotherapy and vaccination respectively. Genetic transformation was also first observed in S. pneumoniae, leading to the discovery of DNA. From a clinical point of view, S. pneumoniae is today still a prime cause of otitis media in children and of pneumonia in all age groups, as well as a predominant cause of meningitis and bacteremia. In adults, bacteremia still has a mortality of over 25%. Although S. pneumoniae remained very sensitive to penicillin for many years, penicillin-resistant strains have emerged and increased dramatically over the last 15 years. During this period the frequency of penicillin-resistant isolates has increased from < or = 1% to frequencies varying from 20 to 60% in geographic areas as diverse as South Africa, Spain, France, Hungary, Iceland, Alaska, and numerous regions of the United States and South America. In Switzerland, the current frequency of penicillin-resistant pneumococci ranges between 5 and > or = 10%. The increase in penicillin-resistant pneumococci correlates with the intensive use of beta-lactam antibiotics. The mechanism of resistance is not due to bacterial production of penicillinase but to an alteration of the bacterial target of penicillin, the so-called penicillin-binding proteins. Resistance is subdivided into (1) intermediate level resistance (minimal inhibitory concentration [MIC] of penicillin of 0.1-1 mg/l) and (2) high level resistance (MCI > or = 2 mg/l). The clinical significance of intermediate resistance remains poorly defined. On the other hand, highly resistant strains have been responsible for numerous therapeutic failures, especially in cases of meningitis. Antibiotics recommended against penicillin-resistant pneumococci include cefotaxime, ceftriaxone, imipenem and in some instances vancomycin. However, penicillin-resistant pneumococci tend to present cross-resistances to all the antibiotics of the beta-lactam family and could even become resistant to the last resort drugs mentioned above. Thus, the explosion of resistance to penicillin in pneumococci is a ubiquitous phenomenon which must be fought against by (1) avoiding excessive use of antibiotics, (2) the practice of microbiological sampling of infected foci before treatment, (3) the systematic surveillance of resistance profiles of pneumococci against antibiotics and (4) adequate vaccination of populations at risk.

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The disjunction of floras between East Asia, Southeast North America, West North America, and Southwest Eurasia has been interpreted in terms of the fragmentation of a once continuous mixed mesophytic forest that occurred throughout the Northern Hemisphere due to the climatic and geological changes during the late Tertiary. The sword moss, Bryoxiphium, exhibits a distribution that strikingly resembles that of the mesophytic forest elements such as Liriodendron and is considered as the only living member of an early Tertiary flora in Iceland. These hypotheses are tested here using molecular dating analyses and ancestral area estimations. The results suggest that the extant range of Bryoxiphium results from the fragmentation of a formerly wider range encompassing North America and Southeast Asia about 10 million years ago. The split of continental ancestral populations is too recent to match with a continental drift scenario but is spatially and temporally remarkably congruent with that observed in Tertiary angiosperm relict species. The timing of the colonization of Iceland from Macaronesian ancestors, about two million years ago, is, however, incompatible with the hypothesis that Bryoxiphium is the only living member of an early Tertiary flora of the island. Alaska was recurrently colonized from East Asia. The ability of Bryoxiphium to overcome large oceanic barriers is further evidenced by its occurrence on remote oceanic archipelagos. In particular, Madeira was colonized twice independently from American and East Asian ancestors, respectively. The striking range disjunction of Bryoxiphium is interpreted in terms of its mating system, as the taxon exhibits a very singular pattern of spatial segregation of the sexes.

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Kartta kuuluu A. E. Nordenskiöldin kokoelmaan

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The semipalmated sandpiper Calidris pusilla and the spotted sandpiper Actitis macularia are long- and short-distance migrants, respectively. C. pusilla breeds in the sub-arctic and mid-arctic tundra of Canada and Alaska and winters on the north and east coasts of South America. A. macularia breeds in a broad distribution across most of North America from the treeline to the southern United States. It winters in the southern United States, and Central and South America. The autumn migration route of C. pusilla includes a non-stop flight over the Atlantic Ocean, whereas autumn route of A. macularia is largely over land. Because of this difference in their migratory paths and the visuo-spatial recognition tasks involved, we hypothesized that hippocampal volume and neuronal and glial numbers would differ between these two species. A. macularia did not differ from C. pusilla in the total number of hippocampal neurons, but the species had a larger hippocampal formation and more hippocampal microglia. It remains to be investigated whether these differences indicate interspecies differences or neural specializations associated with different strategies of orientation and navigation.

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Every German consumes per year, 15% is salmon, which is the third most popular fish in Germany after Alaska-Seelachs and Hering (Keller/Kress 2013: 9). But where does the salmon that ends up on our plates every 6th time we eat fish come from? There's no obligation for producers to declare the origin of their fish products, but if they do so, the latin name of the fish, catching method and catch area should be declared. Salmon, of which about 40% are captured in the wild and the rest brought up in aquacultures, could then be declared as follows: Salmon (salmo salar), aquaculture from Chile. Without any doubt, this makes consumption more transparent, but the standards of production – both, social and ecological ones – and the ecological impacts are still kept in the dark.

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Resumen del autor

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Un cuento de Alaska. Relata las aventuras de un perro ovejero que va a vivir con sus dueños, maestros de escuela, a una remota aldea esquimal y cómo él y los habitantes se acostumbran a convivir. Los niños juegan con el perro y un día éste se pierde en las montañas. Todo el mundo en el pueblo lo busca hasta que un vecino de otro pueblo lo lleva a la aldea montando en una moto de nieve.

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Los pueblos azteca e inca crearon grandes imperios en Centroamérica y Sudamérica, respectivamente.Los aztecas, procedentes de Asia, se instalaron primero en Alaska y después en el norte y centro de México, donde fundaron Tenochtitlán y, se expandieron hasta la costa del Golfo de México, en el reinado de Montezuma.Por su parte,los incas se extendieron por los territorios que actualmente corresponden a Perú, Bolivia, Ecuador y parte de Chile y fundaron Cuzco. Aunque ambas civilizaciones fueron destruidas en el siglo XVI por los españoles,conocemos bastante de ellas por las descripciones de los conquistadores y también por la gran cantidad de restos conservados.