Milloin natiivi korjaa ei-natiivin kielioppia keskustelussa?

Summary: When does a native speaker correct the grammar of a non-native speaker in conversation

Biophysical characterization of two different stable misfolded monomeric polypeptides that are chaperone-amenable substrates.

Misfolded polypeptide monomers may be regarded as the initial species of many protein aggregation pathways, which could accordingly serve as primary targets for molecular chaperones. It is therefore of paramount importance to study the cellular mechanisms that can prevent misfolded monomers from entering the toxic aggregation pathway and moreover rehabilitate them into active proteins. Here, we produced two stable misfolded monomers of luciferase and rhodanese, which we found to be differently processed by the Hsp70 chaperone machinery and whose conformational properties were investigated by biophysical approaches. In spite of their monomeric nature, they displayed enhanced thioflavin T fluorescence, non-native β-sheets, and tertiary structures with surface-accessible hydrophobic patches, but differed in their conformational stability and aggregation propensity. Interestingly, minor structural differences between the two misfolded species could account for their markedly different behavior in chaperone-mediated unfolding/refolding assays. Indeed, only a single DnaK molecule was sufficient to unfold by direct clamping a misfolded luciferase monomer, while, by contrast, several DnaK molecules were necessary to unfold the more resistant misfolded rhodanese monomer by a combination of direct clamping and cooperative entropic pulling.

Garlic Mustard: A Serious Threat to Iowa's Woodlands, October 2005

Garlic mustard is a rapidly spreading, highly invasive non-native plant. It was introduced from Europe in mid-1800 for medicinal and herbal uses. Came to the United States without predatory beetles or other natural controls. Threatens to rob us of healthy, diverse native woodlands.

Sobre las fronteras retóricas del español escrito

El artículo explora la presencia de elementos culturales y retóricos procedentes de la lengua nativa (L1) de un autor en sus escritos en segunda lengua (L2). Se resumen y comentan varias investigaciones de la Retórica Contrastiva, los Nuevos Estudios de Literacidad y la Traductología, que analizan las estrategias usadas por autores y traductores para ocultar o mostrar aspectos de su L1 en sus escritos en L2. También se analizan dos casos de escritura académica (de un latino que escribe en inglés y un quechua que lo hace en español), que aportan ejemplos de extralimitaciones en la corrección y de ocultación de rasgos culturales relevantes. Esos datos y las teorías permiten reflexionar sobre la gestión de la retórica y la cultura en los textos de los plurilingües, tanto desde una óptica de la construcción de la identidad como de la corrección de textos en clase.

Recent Observations of the Distribution and Status of Bluntnose Darters and Crystal Darters in Iowa

The distribution and status of Iowa's fishes were last extensively described in Iowa Fish and Fishing (Harlan et al. 1987). Since then, numerous fish collections have been made in Iowa's interior and bordering rivers and streams. Excluding non-native species, there have been three documented accounts of new fish species distributional records in Iowa since 1987. In this paper, I describe new collections of Crystal Darter (Crystallaria asprella) and Bluntnose Darter (Etheostoma chlorosomum) from the Mississippi River. The first documented specimen of C. asprella in Iowa was collected in Pool 11 of the Upper Mississippi River (UMR) in 1995. One specimen of E. chlorosomum was collected in Pool 13 of the UMR in 1998, and another was collected in 1999. The bluntnose darter had not been collected since 1975 and was generally thought to be extirpated in Iowa.

Ain't no mountain high enough: plant invasions reaching new elevations

Most studies of invasive species have been in highly modified, lowland environments, with comparatively little attention directed to less disturbed, high-elevation environments. However, increasing evidence indicates that plant invasions do occur in these environments, which often have high conservation value and provide important ecosystem services. Over a thousand non-native species have become established in natural areas at high elevations worldwide, and although many of these are not invasive, some may pose a considerable threat to native mountain ecosystems. Here, we discuss four main drivers that shape plant invasions into high-elevation habitats: (1) the (pre-)adaptation of non-native species to abiotic conditions, (2) natural and anthropogenic disturbances, (3) biotic resistance of the established communities, and (4) propagule pressure. We propose a comprehensive research agenda for tackling the problem of plant invasions into mountain ecosystems, including documentation of mountain invasion patterns at multiple scales, experimental studies, and an assessment of the impacts of non-native species in these systems. The threat posed to high-elevation biodiversity by invasive plant species is likely to increase because of globalization and climate change. However, the higher mountains harbor ecosystems where invasion by non-native species has scarcely begun, and where science and management have the opportunity to respond in time.

Heavy metal ions are potent inhibitors of protein folding.

Environmental and occupational exposure to heavy metals such as cadmium, mercury and lead results in severe health hazards including prenatal and developmental defects. The deleterious effects of heavy metal ions have hitherto been attributed to their interactions with specific, particularly susceptible native proteins. Here, we report an as yet undescribed mode of heavy metal toxicity. Cd2+, Hg2+ and Pb2+ proved to inhibit very efficiently the spontaneous refolding of chemically denatured proteins by forming high-affinity multidentate complexes with thiol and other functional groups (IC(50) in the nanomolar range). With similar efficacy, the heavy metal ions inhibited the chaperone-assisted refolding of chemically denatured and heat-denatured proteins. Thus, the toxic effects of heavy metal ions may result as well from their interaction with the more readily accessible functional groups of proteins in nascent and other non-native form. The toxic scope of heavy metals seems to be substantially larger than assumed so far.

1009-004 Lost Island Lake Watershed Final Report

The Lost Island Lake watershed is located in the prairie pothole region, a region dotted with glacial wetlands and shallow lakes. At 1,180 acres, Lost Island Lake is the state's fifth largest natural lake and its watershed is comprised of nearly 1,000 acres of wetland habitat, including Iowa 's largest natural wetland – Barringer Slough. Unfortunately, Lost Island and its associated wetlands are not functioning to their fullest ecological and water quality potential. In 2002 and 2004, Lost Island Lake was categorized as '·impaired'" on Iowa's Impaired Waters List. Frequent algal blooms and suspended solids drastically increase turbidity levels resulting in its impairment. To investigate these concerns, a two-year study and resulting Water Quality Improvement Plan were completed. The water quality study identified an overabundance of non-native common carp (Cyprinus carpio) in the lake and its surrounding wetlands as a primary cause of impairment. The goal of the Lost Island Lake Watershed Enhancement Project is to restore ecological health to Lost Island Lake and its intricate watershed resulting in improved water quality and a diverse native plant and wildlife community. The purpose of this grant is to obtain funding for the construction of two combination fish barriers and water control structures placed at key locations in the watershed within the Blue Wing Marsh complex. Construction of the fish barriers and water control structures would aid restoration efforts by preventing spawning common carp from entering wetlands in the watershed and establishing the ability to manage water levels in large wetland areas. Water level management is crucial in wetland health and exotic fish control. These two structures are part of a larger construction project that involves a total of four combination fish barriers and water control structures and one additional fish barrier. The entire Lost Island Lake Watershed Enhancement Project is a multi-year project, but the construction phase for the fish barriers and water control structures will be completed before December 31, 2011.

Hajautetun järjestelmäkehityksen soveltaminen

Hajautetulla järjestelmäkehityksellä tarkoitetaan tietojärjestelmän kehitysprojektin hajauttamista maantieteellisesti jakamalla projektiryhmä virtuaalitiimeiksi eri paikkakunnille tai eri maihin. Tässä diplomityössä tutustutaan hajautettuun järjestelmäkehitykseen käsitteenä sekä perehdytään kehitysprosessin hajauttamisen ja virtuaalitiimien käytön potentiaalisiin hyötyihin ja ongelmiin sekä kirjallisuuden että eräässä yrityksessä toteutetun projektin pohjalta, sekä kirjallisuudessaesiintyviin ratkaisuihin riskien pitämiseksi mahdollisimman pieninä. Tältä pohjalta etsitään keskeisimmät projektin onnistumiseen vaikuttavat tekijät. Työssä haetaan kirjallisuudessa esitettyjä keinoja yhdistämällä ratkaisuja virtuaalitiimien potentiaalisten hyötyjen toteuttamiseksi ja riskien välttämiseksi. Kehitettyjä ratkaisuja tarkastellaan sekä kirjallisuuden esimerkkitapausten, että hajautetusta järjestelmäkehitysprojektista saatujen omakohtaisten käytännön kokemusten valossa. Työssä luodaan myös silmäys hajautettua työskentelyätukeviin työkaluihin. Kirjallisuuden ja osin myös käytännön kokemusten pohjalta merkittävimmiksi hajautetun järjestelmäkehitystyön tukemisessa osoittautuivat työryhmän viestinnän tukeminen, erityisesti silloin kun ryhmänjäsenet eivät voi käyttää äidinkieltään, ryhmän jäsenten välisen luottamuksen ja yhteenkuuluvuuden luominen, sekä työn koordinointi.

Physical interaction between bacterial heat shock protein (Hsp) 90 and Hsp70 chaperones mediates their cooperative action to refold denatured proteins.

In eukaryotes, heat shock protein 90 (Hsp90) is an essential ATP-dependent molecular chaperone that associates with numerous client proteins. HtpG, a prokaryotic homolog of Hsp90, is essential for thermotolerance in cyanobacteria, and in vitro it suppresses the aggregation of denatured proteins efficiently. Understanding how the non-native client proteins bound to HtpG refold is of central importance to comprehend the essential role of HtpG under stress. Here, we demonstrate by yeast two-hybrid method, immunoprecipitation assays, and surface plasmon resonance techniques that HtpG physically interacts with DnaJ2 and DnaK2. DnaJ2, which belongs to the type II J-protein family, bound DnaK2 or HtpG with submicromolar affinity, and HtpG bound DnaK2 with micromolar affinity. Not only DnaJ2 but also HtpG enhanced the ATP hydrolysis by DnaK2. Although assisted by the DnaK2 chaperone system, HtpG enhanced native refolding of urea-denatured lactate dehydrogenase and heat-denatured glucose-6-phosphate dehydrogenase. HtpG did not substitute for DnaJ2 or GrpE in the DnaK2-assisted refolding of the denatured substrates. The heat-denatured malate dehydrogenase that did not refold by the assistance of the DnaK2 chaperone system alone was trapped by HtpG first and then transferred to DnaK2 where it refolded. Dissociation of substrates from HtpG was either ATP-dependent or -independent depending on the substrate, indicating the presence of two mechanisms of cooperative action between the HtpG and the DnaK2 chaperone system.

Inmigración e interacción en la enseñanza/adquisición de lenguas: la construcción conversacional del alumnado de origen inmigrante

Además de presentar la interacción en el aula desde la perspectiva del trabajo en parejas alumno autóctono/no autóctono, nuestro objetivo en el presente apartado de este volumen es analizar los procesos interactivos que llevan a que una misma tarea escolar se resuelva de manera más o menos eficiente. Al mismo tiempo, contemplamos y comparamos en nuestro análisis la interacción que tiene lugar entre dos parejas de alumnos (alumna inmigrante/alumno autóctono) en la resolución de tareas escolares en lengua inglesa, prestando especial atención a cómo y en qué medida los interlocutores se orientan interactivamente hacia la identidad del alumno inmigrante.

A melting pot world of species : reply to Speziale et al.

Native plants and animals are a natural heritage threatened by one of the six greatest extinction events in Earth's history. Humans, through habitat transformation, exploitation, and species introductions, are driving this extinction event. To turn this tide, Speziale et al. (2014) suggest reducing human dependence on non-native species by increasing the use, harvest, planting, and raising of native species, thereby increasing their cultural and economic value. The search for new or under-appreciated uses of native species is laudable, especially if it helps protect them and contributes to local cultural diversity. Such efforts are arguably an inherent trait of human curiosity and entrepreneurship and are a central platform of popular movements such as slow foods and native gardening. However, Speziale et al.'s hypothesis - that using native species can protect them - is less simple than they suggest. We refute the idea of nativism that underpins Speziale et al.'s proposal and makes it poorly defensible and considered the unaddressed consequences of the proposal for people and for conservation.

Synergism between a foldase and an unfoldase: reciprocal dependence between the thioredoxin-like activity of DnaJ and the polypeptide-unfolding activity of DnaK.

The role of bacterial Hsp40, DnaJ, is to co-chaperone the binding of misfolded or alternatively folded proteins to bacterial Hsp70, DnaK, which is an ATP-fuelled unfolding chaperone. In addition to its DnaK targeting activity, DnaJ has a weak thiol-reductase activity. In between the substrate-binding domain and the J-domain anchor to DnaK, DnaJ has a unique domain with four conserved CXXC motives that bind two Zn(2+) and partly contribute to polypeptide binding. Here, we deleted in DnaJ this Zn-binding domain, which is characteristic to type I but not of type II or III J-proteins. This caused a loss of the thiol-reductase activity and strongly reduced the ability of DnaJ to mediate the ATP- and DnaK-dependent unfolding/refolding of mildly oxidized misfolded polypeptides, an inhibition that was alleviated in the presence of thioredoxin or DTT. We suggest that in addition to their general ability to target misfolded polypeptide substrates to the Hsp70/Hsp110 chaperone machinery, Type I J-proteins carry an ancillary protein dithiol-isomerase function that can synergize the unfolding action of the chaperone, in the particular case of substrates that are further stabilized by non-native disulfide bonds. Whereas the unfoldase can remain ineffective without the transient untying of disulfide bonds by the foldase, the foldase can remain ineffective without the transient ATP-fuelled unfolding of wrong local structures by the unfoldase.

Will climate change increase the risk of plant invasions into mountains?

Mountain ecosystems have been less adversely affected by invasions of non-native plants than most other ecosystems, partially because most invasive plants in the lowlands are limited by climate and cannot grow under harsher high-elevation conditions. However, with ongoing climate change, invasive species may rapidly move upwards and threaten mid- then high-elevation mountain ecosystems. We evaluated this threat by predicting current and future potential distributions of 48 invasive plant species distributed in Switzerland (CH) and New South Wales (NSW), two areas where climate interacts differently with the elevation gradient. Using a species distribution modeling approach combining two scales, which builds on high-resolution data (< 250 m) but accounts for the global climatic niche of species, we found that different environmental drivers limit the elevation range of invasive species in the two regions, leading to region-specific species responses to climate change. Whereas the optimal suitability for plant invaders is predicted to markedly shift from the lowland to the montane or subalpine zone in CH, such an upward shift is far less pronounced in NSW where montane and subalpine elevations are currently already suitable. Non-native species able to invade the upper reaches of mountains in a future climate will be cold-tolerant in the Swiss Alps but preferring wet soils in the Australian Alps. Other plant traits were only marginally associated with elevation limits. These results demonstrate that a more systematic consideration of future distributions of invasive species is required in conservation plans of not yet invaded mountainous ecosystems.