797 research outputs found
Distribution of diatoms in relation to the character of water masses and currents off southern California in 1938
In 1938 the E.W. Scripps made six cruises at intervals of two months, covering on each cruise the same area off the coast of southern California. The station plan is shown in Figure 37, but not all stations indicated in that figure could be occupied on each cruise owing to unfavorable weather conditions and the short time available for completion of the work. On all cruises observations of temperature, salinity, and oxygen were made between the surface and a depth of 600 meters...
A repurposing strategy for Hsp90 inhibitors demonstrates their potency against filarial nematodes
Novel drugs are required for the elimination of infections caused by filarial worms, as most commonly used drugs largely target the microfilariae or first stage larvae of these infections. Previous studies, conducted in vitro, have shown that inhibition of Hsp90 kills adult Brugia pahangi. As numerous small molecule inhibitors of Hsp90 have been developed for use in cancer chemotherapy, we tested the activity of several novel Hsp90 inhibitors in a fluorescence polarization assay and against microfilariae and adult worms of Brugia in vitro. The results from all three assays correlated reasonably well and one particular compound, NVP-AUY922, was shown to be particularly active, inhibiting Mf output from female worms at concentrations as low as 5.0 nanomolar after 6 days exposure to drug. NVP-AUY922 was also active on adult worms after a short 24 h exposure to drug. Based on these in vitro data, NVP-AUY922 was tested in vivo in a mouse model and was shown to significantly reduce the recovery of both adult worms and microfilariae. These studies provide proof of principle that the repurposing of currently available Hsp90 inhibitors may have potential for the development of novel agents with macrofilaricidal properties
Psykososialt arbeidsmiljø på tre servicekontor i offentlig sektor – hvordan opplever medarbeiderne sin yrkeshverdag?
Denne rapporten omhandler hvordan ansatte i førstelinjen i offentlig sektor opplever sitt
arbeidsmiljø. Undersøkelsen ble gjennomført ved tre servicekontor i offentlig sektor. Det ble
foretatt 8 intervjuer med frontservice personell om deres oppfattelse av det psykososiale
arbeidsmiljøet. Målet med undersøkelsen var to delt. For det første, å sammenligne
resultatene fra de tre kontorene for å se om det var noen fellestrekk eller ikke i det
psykososiale arbeidsmiljøet, og om disse eventuelle fellestrekkene i arbeidsmiljøet kan si noe
om generelle arbeidsmiljøbetingelser i serviceyrket i offentlig sektor. Eller er det slik at hvert
individ med sine personlige forutsetninger opplever arbeidsmiljøet forskjellig?
For det andre, å finne nye problemstillinger og tema når det gjelder frontservice og
psykososialt arbeidsmiljø, som kan være aktuelle å undersøke videre. Resultatene viste at
fellestrekkene i arbeidsmiljøet viste seg å omfatte store deler av det fysiske arbeidsmiljøet,
herunder støy, luftkvalitet og temperatur. I tillegg var det viktig å være sosial og kunne
samarbeide. Videre oppfattet alle de spurte arbeidsdagen som hektisk, og at de hadde liten
mulighet til å bestemme tempo og planlegge arbeidsdagen selv. Spennvidden lå i hvilke
utfordringer de følte de hadde i arbeidet, hvilke evner de følte de fikk brukt, og forventninger
til arbeidet. Det ble avdekket flere tema og problemstillinger som kan være aktuelle å
undersøke videre, herunder; tiltak for å bedre arbeidsmiljøet, dilemmaet i ”forvaltningens to
ansikter”, omstilling i offentlig sektor konsekvenser for arbeidsmiljø samt omfanget av stress
og emosjonell utmattelse blant førstelinjen. Ved økt fokus på det psykososiale arbeidsmiljøet,
kan en ved å avdekke hvilke arbeidsmiljøbetingelser som er generelle, finne ut hvilke tiltak
som bør igangsettes for å bedre hverdagen i førstelinjen.English: This article concerns how employees in front service in public sector perceive the
psychosocial work environment. The study was conducted in three front service offices in
public sector. 8 interviews with front service personnel were carried out in order to reveal
their perception of the psychosocial environment at their workplace. The aim of the study was
twofold. First, to compare the results from the three offices in order to identify similarities or
not in the psychosocial work environment, and whether or not these potential similarities in
the psychosocial work environment can tell us if there exists any general work environment
conditions in front service in public sector. Or is it so that every individual with its personal
preferences perceives the psychosocial environment at their workplace differently? Second, to
discover new subjects and approaches in front service and psychosocial work environment
that can lead to further studies. The results showed that the similarities to a large extent
included the physical work environment, hereby noise, air quality and temperature. Also, it
seemed to be important to be able to cooperate and to be social. Further, they all agreed that
their working day was rather hectic, and that they had minor possibilities to decide the pace at
work, and to plan their working day. The variation constituted the employees’ perceptions
about challenges at work, which abilities they felt they used, and expectations towards work.
Several subjects and approaches were discovered, such as; plans to improve the psychosocial
work environment, the dilemma of “the public administrators two faces”, reorganization in
public sector and consequences for psychosocial work environment, and the amount of stress
and emotional exhaustion among front service personnel. Through increased focus on the
psychosocial work environment, one can reveal which conditions of the psychosocial work
environment that are general, and hence create plans for making a better work environment for
front service personnel
The use of field data from the faulted margin of the gulf of Corinth as input to the reservoir model of the Lavrans Field, Haltenbanken, offshore Norway
Large proportions of the structural features that can impact on the flow properties of a reservoir are below the resolution of seismic data. Understanding the spatial distribution and internal structure of faults is therefore fundamental. By using a field analogue from the southern margin of the Gulf of Corinth, we have obtained information about fault parameters like frequency, orientation and linkage, which have been used in the reservoir modelling process of the Lavrans Field, offshore Norway. The link between field observations, seismic interpretation and plaster modelling techniques has further guided us to describe the structural development of the investigated structures
Quantitative localized proton-promoted dissolution kinetics of calcite using scanning electrochemical microscopy (SECM)
Scanning electrochemical microscopy (SECM) has been used to determine quantitatively the kinetics of proton-promoted dissolution of the calcite (101̅4) cleavage surface (from natural “Iceland Spar”) at the microscopic scale. By working under conditions where the probe size is much less than the characteristic dislocation spacing (as revealed from etching), it has been possible to measure kinetics mainly in regions of the surface which are free from dislocations, for the first time. To clearly reveal the locations of measurements, studies focused on cleaved “mirror” surfaces, where one of the two faces produced by cleavage was etched freely to reveal defects intersecting the surface, while the other (mirror) face was etched locally (and quantitatively) using SECM to generate high proton fluxes with a 25 μm diameter Pt disk ultramicroelectrode (UME) positioned at a defined (known) distance from a crystal surface. The etch pits formed at various etch times were measured using white light interferometry to ascertain pit dimensions. To determine quantitative dissolution kinetics, a moving boundary finite element model was formulated in which experimental time-dependent pit expansion data formed the input for simulations, from which solution and interfacial concentrations of key chemical species, and interfacial fluxes, could then be determined and visualized. This novel analysis allowed the rate constant for proton attack on calcite, and the order of the reaction with respect to the interfacial proton concentration, to be determined unambiguously. The process was found to be first order in terms of interfacial proton concentration with a rate constant k = 6.3 (± 1.3) × 10–4 m s–1. Significantly, this value is similar to previous macroscopic rate measurements of calcite dissolution which averaged over large areas and many dislocation sites, and where such sites provided a continuous source of steps for dissolution. Since the local measurements reported herein are mainly made in regions without dislocations, this study demonstrates that dislocations and steps that arise from such sites are not needed for fast proton-promoted calcite dissolution. Other sites, such as point defects, which are naturally abundant in calcite, are likely to be key reaction sites
Specialists in ancient trees are more affected by climate than generalists
Ancient trees are considered one of the most important habitats for biodiversity in Europe and North America. They support exceptional numbers of specialized species, including a range of rare and endangered wood-living insects. In this study, we use a dataset of 105 sites spanning a climatic gradient along the oak range of Norway and Sweden to investigate the importance of temperature and precipitation on beetle species richness in ancient, hollow oak trees. We expected that increased summer temperature would positively influence all wood-living beetle species whereas precipitation would be less important with a negligible or negative impact. Surprisingly, only oak-specialist beetles with a northern distribu- tion increased in species richness with temperature. Few specialist beetles and no generalist beetles responded to the rise of 4°C in summer as covered by our cli- matic gradient. The negative effect of precipitation affected more specialist species than did temperature, whereas the generalists remained unaffected. In summary, we suggest that increased summer temperature is likely to benefit a few specialist beetles within this dead wood community, but a larger number of specialists are likely to decline due to increased precipitation. In addition, generalist species will remain unaffected. To minimize adverse impacts of climate change on this impor- tant community, long-term management plans for ancient trees are important
Planktonic events may cause polymictic-dimictic regime shifts in temperate lakes
Water transparency affects the thermal structure of lakes, and within certain lake depth ranges, it can determine whether a lake mixes regularly (polymictic regime) or stratifies continuously (dimictic regime) from spring through summer. Phytoplankton biomass can influence transparency but the effect of its seasonal pattern on stratification is unknown. Therefore we analysed long term field data from two lakes of similar depth, transparency and climate but one polymictic and one dimictic, and simulated a conceptual lake with a hydrodynamic model. Transparency in the study lakes was typically low during spring and summer blooms and high in between during the clear water phase (CWP), caused when zooplankton graze the spring bloom. The effect of variability of transparency on thermal structure was stronger at intermediate transparency and stronger during a critical window in spring when the rate of lake warming is highest. Whereas the spring bloom strengthened stratification in spring, the CWP weakened it in summer. The presence or absence of the CWP influenced stratification duration and under some conditions determined the mixing regime. Therefore seasonal plankton dynamics, including biotic interactions that suppress the CWP, can influence lake temperatures, stratification duration, and potentially also the mixing regime
Characterization and Whole Genome Analysis of Human Papillomavirus Type 16 E1-1374^63nt Variants
Background. The variation of the most common Human papillomavirus (HPV) type found in cervical cancer, the HPV16, has been extensively investigated in almost all viral genes. The E1 gene variation, however, has been rarely studied. The main objective of the present investigation was to analyze the variability of the E6 and E1 genes, focusing on the recently identified E1-1374^63nt variant. Methodology/Principal Findings. Variation within the E6 of 786 HPV16 positive cervical samples was analyzed using high-resolution melting, while the E1-1374^63nt duplication was assayed by PCR. Both techniques were supplemented with sequencing. The E1-1374^63nt duplication was linked with the E-G350 and the E-C109/G350 variants. In comparison to the referent HPV16, the E1-1374^63nt E-G350 variant was significantly associated with lower grade cervical lesions (p=0.029), while the E1-1374^63nt E-C109/G350 variant was equally distributed between high and low grade lesions. The E1-1374^63nt variants were phylogenetically closest to E-G350 variant lineage (A2 sub-lineage based on full genome classification). The major differences between E1-1374^63nt variants were within the LCR and the E6 region. On the other hand, changes within the E1 region were the major differences from the A2 sub-lineage, which has been historically but inconclusively associated with high grade cervical disease. Thus, the shared variations cannot explain the particular association of the E1-1374^63nt variant with lower grade cervical lesions. Conclusions/Significance. The E1 region has been thus far considered to be well conserved among all HPVs and therefore uninteresting for variability studies. However, this study shows that the variations within the E1 region could possibly affect cervical disease, since the E1-1374^63nt E-G350 variant is significantly associated with lower grade cervical lesions, in comparison to the A1 and A2 sub-lineage variants. Furthermore, it appears that the silent variation 109T>C of the E-C109/G350 variant might have a significant role in the viral life cycle and warrants further study
Geomicrobiology of the built environment
Microbial colonization and growth can have significant effects in the built environment, resulting in a range of effects from discolouration and staining to biodeterioration and decay. In some cases, formation of biofilms, crusts and patinas may confer bioprotection of the substrate. This perspective aims to discuss how geomicrobial transformations in the natural environment - particularly involving rocks, minerals, metals and organic matter - may be applied to understand similar processes occurring on fabricated human structures. However, the built environment may offer further strictures as well as benefits for microbial activity and these should be taken into consideration when considering analogy with natural processes, especially when linking observations of microbial biodiversity to the more obvious manifestations of microbial attack
- …
