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How can the traditional fourfold aim: To read, to understand, to speak and to write the foreign language be attained in the limited time of the two-year college course?
Nectar-Inhabiting Bacteria Affect Olfactory Responses of an Insect Parasitoid by Altering Nectar Odors
Floral nectar is ubiquitously colonized by a variety of microorganisms among which yeasts and bacteria are the most common. Microorganisms inhabiting floral nectar can alter several nectar traits, including nectar odor by producing microbial volatile organic compounds (mVOCs). Evidence showing that mVOCs can affect the foraging behavior of insect pollinators is increasing in the literature, whereas the role of mVOCs in altering the foraging behavior of third-trophic level organisms such as insect parasitoids is largely overlooked. Parasitoids are frequent visitors of flowers and are well known to feed on nectar. In this study, we isolated bacteria inhabiting floral nectar of buckwheat, Fagopyrum esculentum (Polygonales: Polygonaceae), to test the hypothesis that nectar bacteria affect the foraging behavior of the egg parasitoid Trissolcus basalis (Hymenoptera: Scelionidae) via changes in odors of nectar. In behavioral assays, we found that T. basalis wasps are attracted toward nectar fermented by 4 out of the 14 bacterial strains isolated, which belong to Staphylococcus epidermidis, Terrabacillus saccharophilus (both Firmicutes), Pantoea sp. (Proteobacteria), and Curtobacterium sp. (Actinobacteria). Results of chemical investigations revealed significant differences in the volatile blend composition of nectars fermented by the bacterial isolates. Our results indicate that nectar-inhabiting bacteria play an important role in the interactions between flowering plants and foraging parasitoids. These results are also relevant from an applied perspective as flowering resources, such as buckwheat, are largely used in agriculture to promote conservation biological control of insect pests
The indirect effect of nectar-inhabiting yeasts on olfactory responses and longevity of two stink bug egg parasitoids
Adult parasitoids are well known to feed on sugar-rich resources such as floral nectar. Recently, an increasing body of evidence has shown that nectar is ubiquitously colonized by microorganisms and, as a consequence, microbial metabolic activity can affect several traits of floral nectar. Yet, how the fermentation of nectar by yeasts impacts the olfactory responses and performance of parasitoids is largely understudied, especially in the case of egg parasitoids. In this study, we investigated whether fermentation by the nectar yeasts Metschnikowia gruessii and M. reukaufii affects the olfactory responses of Trissolcus basalis and Ooencyrtus telenomicida, two egg parasitoid species associated with the southern green stink bug Nezara viridula. We also investigated how yeast fermentation affects the longevity and survival of the egg parasitoids. Results of static four-chamber olfactometer tests showed that nectar fermented by M. gruessii (but not by M. reukaufii) was attractive to both egg parasitoid species, whereas no significant yeast-mediated effects were found in terms of wasp longevity. Gas chromatography coupled with mass spectrometry (GC-MS) showed a clear separation of the volatile profiles among M. gruessii, M. reukaufii and non-fermented control nectar supporting the results of the insect bioassays. The results of our study highlight the need to consider the role of microbes when studying interactions between flower nectar and egg parasitoids and could have implications from a conservation biological control perspective
A microwave resonator integrated on a polymer microfluidic chip
We describe a novel stacked split-ring type microwave (MW) resonator that is integrated into a 10 mm by 10 mm sized microfluidic chip. A straightforward and scalable batch fabrication process renders the chip suitable for single-use applications. The resonator volume can be conveniently loaded with liquid sample via microfluidic channels patterned into the mid layer of the chip. The proposed MW resonator offers an alternative solution for compact in-field measurements, such as low-field magnetic resonance (MR) experiments requiring convenient sample exchange. A microstrip line was used to inductively couple MWs into the resonator. We characterised the proposed resonator topology by electromagnetic (EM) field simulations, a field perturbation method, as well as by return loss measurements. Electron paramagnetic resonance (EPR) spectra at X-band frequencies were recorded, revealing an electron-spin sensitivity of View the MathML source3.7·1011spins·Hz-1/2G-1 for a single EPR transition. Preliminary time-resolved EPR experiments on light-induced triplet states in pentacene were performed to estimate the MW conversion efficiency of the resonator
Oscillator strengths for transitions to Rydberg levels in , and between 967 and 972 A
Absorption oscillator strengths have been determined from high-resolution
spectra in the 967-972 \AA region of three CO isotopomers for transitions to
the Rydberg levels 4{\it p}(0), 3{\it d}(1) and 4{\it p}(0),
as well as to the mixed {\it E(6)} level recently characterized by Eidelsberg
et al. (2004). Synchrotron radiation from the Super-ACO electron storage ring
at Orsay (LURE) was used as a light source. Oscillator strengths were extracted
from the recorded spectra by least-squares fitting of the experimental profiles
with synthetic spectra taking into account the homogeneous and heterogeneous
interactions of the four levels. Column densities were derived from fits to the
3{\it p}(0) absorption band whose oscillator strength is well established.
These are the first reported measurements for CO. For
CO, our results are consistent with the larger values obtained in
the most recent laboratory and astronomical studies.Comment: 9 pages 7 figures 3 tables. Accepted in A&A, date of acceptance
11/05/200
Oscillator Strengths and Predissociation Rates for Rydberg Transitions in 12C16O, 13C16O, and 13C18O Involving the E 1Pi, B 1Sigma+, and W 1Pi States
One of the processes controlling the interstellar CO abundance and the ratio
of its isotopologues is photodissociation. Accurate oscillator strengths and
predissociation rates for Rydberg transitions are needed for modeling this
process. We present results on absorption from the E ^1Pi-X ^1Sigma^+ (1-0) and
B ^1Sigma^+-X ^1Sigma^+ (6-0) bands at 1051 and 1002 \AA, respectively, and the
vibrational progression W ^1Pi-X ^1Sigma^+ (v'-0) bands with v' = 0 to 3 at
972, 956, 941, and 925 \AA, respectively. The corresponding spectra were
acquired at the high resolution (R ~ 30,000) SU5 beam line at the Super ACO
Synchrotron in Orsay, France. Spectra were obtained for the ^12C^16O, ^13C^16O,
and ^13C^18O isotopologues. These represent the most complete set of
measurements available. Comparison is made with earlier results, both empirical
and theoretical. While earlier determinations of oscillator strengths based on
absorption from synchrotron radiation tend to be somewhat smaller than ours,
the suite of measurements from a variety of techniques agree for the most part
considering the mutual uncertainties. For the bands studied here, their
relative weakness, or their significant line widths arising from
predissociation, minimizes potential problems from large optical depths at line
center in absorption measurements. Predissociating line widths could generally
be extracted from the spectra thanks to the profile simulations used in the
analysis. In many cases, these simulations allowed us to consider e and f
parity levels separately and to determine the dependence of the width on
rotational quantum number, J. Our results are consistent with earlier
determinations, especially the widths inferred from laser experiments
Supporting Roma Voices
The Supporting Roma Voice project has aimed to
address emerging knowledge gaps in the way in
which the inclusion of migrant Roma in the UK is
being addressed. Specifically, research by Brown,
Scullion and Martin (2013) identified a demand
from public authorities for social inclusion work
directed towards migrant Roma communities to be
developed and delivered by members of migrant
Roma communities themselves. However, what was
also lacking was an adequate evidence base about
the settlement of migrant Roma in the UK and the
varied experiences associated with this transition.
This report explores the views and experiences of a
large number of Roma people who have migrated
to the UK in recent years. The research was
designed in partnership with a team of researchers
from the Roma communities and undertaken
wholly by these researchers. The research study
aimed to explore the following issues:
- The settlement and integration experiences of
Roma migrants living in areas across the UK.
- The specific areas of community relations,
housing, education, employment and social
welfare and their role in settlement in the UK.
- The provision of knowledge that would enable
local authorities and other services to enhance
the settlement experience of Roma migrants
now and in the future.
A total of 159 people participated in 19 focus
groups, which took place in the following locations:
Glasgow, Leicester, London, Oldham, Salford and
Sheffield. It should be noted that owing to the
heterogeneity of the Roma population this report
does not attempt to make definitive statements
about the situation and views of all Roma
migrants in the UK. This report was co-authored
by members of the academic team in partnership
with community researchers. The fieldwork
was undertaken in early 2016 prior to the UK’s
referendum on staying in the European Union
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