871 research outputs found
Efficient all-optical production of large Li quantum gases using D gray-molasses cooling
We use a gray molasses operating on the D atomic transition to produce
degenerate quantum gases of Li with a large number of atoms. This
sub-Doppler cooling phase allows us to lower the initial temperature of 10
atoms from 500 to 40 K in 2 ms. We observe that D cooling remains
effective into a high-intensity infrared dipole trap where two-state mixtures
are evaporated to reach the degenerate regime. We produce molecular
Bose-Einstein condensates of up to 510 molecules and
weakly-interacting degenerate Fermi gases of 10 atoms at
with a typical experimental duty cycle of 11 seconds.Comment: 5 pages, 3 figure
Representing their own? Ethnic minority women in the Dutch parliament
Ethnic minority women tend to be better represented in parliaments than ethnic minority men. What does this mean for their substantive representation? This article makes use of intersectional analysis to study how the relationship between descriptive and substantive representation differs within and between gender and ethnic groups. Drawing on written parliamentary questions and the committee memberships of MPs in seven parliamentary sessions (1995-2012) in the Netherlands, a strong link is found between descriptive and substantive representation. Female ethnic minority MPs more often sit on committees and table questions that address ethnic minority women's interests than male ethnic minority and female ethnic majority MPs. The link, however, is fragile as it is based on a small number of active MPs. This demonstrates the importance of an intersectional approach to understanding how representation works in increasingly diverse parliaments, which cannot be captured by focusing on gender or ethnicity alone
Muscle transcriptomes of Duroc and Pietrain pig breeds during prenatal formation of skeletal muscle tissue using microarray technology
Mammalian myogenesis is an exclusive prenatal process regulated by the muscle regulatory factor gene family, which itself is regulated by numerous other genes. We developed a microarray consisting of the clones of two muscle-specific cDNA libraries with the addition of 500 genes with known function in myogenesis and energy metabolism. Tissue samples were collected of Duroc and Pietrain prenatal litters of 14 and 21 days of age (complete embryos) and 35, 49, 63, 77, and 91 days of age (longissimus muscle tissue) and RNA was isolated. Microarrays were hybridised with pools of six RNA samples. For each age comparisons between Duroc and Pietrain breeds were made, and transcriptome profile changes in time were made for Duroc pigs. Comparison of Duroc and Pietrain prenatal muscle transcriptome expression profiles revealed differences in myogenesis regulating genes, suggesting differential timing of myogenesis between the two pig breeds. The differential development of the expression of the muscle structural genes strengthens this conclusion. Furthermore, differences in the expression of the energy metabolism genes were found. The results also suggest that the differential fat content between the Duroc and Pietrain pig breeds already starts to develop during early prenatal development. The changes in the muscle transcriptome expression profiles during Duroc prenatal muscle development shows a profile of waves of expression of (i) myoblast proliferation stimulating genes,(ii) followed by myoblast proliferation inhibiting and differentiation stimulating genes during the primary muscle fibre development, which is repeated with lower magnitude during secondary muscle fibre development. Furthermore, expression of energy metabolism genes reaches a nadir when differentiation of myoblasts into myotubes takes place. Microarray expression profiles were validated with five genes showing differential expression in the Duroc ¿ Pietrain comparison, and in the Duroc development in time studies using 18S rRNA for normalisation. The real time PCR confirmed the microarray result
Long-wave infrared super-resolution wide-field microscopy using sum-frequency generation
Super-resolution microscopy in the visible is an established powerful tool in various disciplines. In the long-wave infrared (LWIR) spectral range, however, no comparable schemes have been demonstrated to date. In this work, we experimentally demonstrate super-resolution microscopy in the LWIR range (λIR ≈ 10–12 μm) using IR-visible sum-frequency generation. We operate our microscope in a wide-field scheme and image localized surface phonon polaritons in 4H-SiC nanostructures as a proof-of-concept. With this technique, we demonstrate an enhanced spatial resolution of ~λIR/9, enabling to resolve the polariton resonances in individual sub-diffractional nanostructures with sub-wavelength spacing. Furthermore, we show that this resolution allows us to differentiate between spatial patterns associated with different polariton modes within individual nanostructures
Cerebral blood flow and heart rate variability in chronic fatigue syndrome : a randomized cross-over study
Background: Pain, fatigue, and concentration difficulties are typical features of chronic fatigue syndrome (CFS). The exact underlying mechanisms of these symptoms are still unknown, but available evidence suggests an important role for impaired pain modulation. As evidence also suggests that pain modulation is related to cardiovascular mechanisms, it seems logical to investigate whether cerebral blood flow (CBF) and heart rate variability (HRV) are altered in these patients.
Objectives: We aimed to investigate the role of the cardiovascular system in pain modulation and symptoms of CFS; the response of CBF and HRV to physical stress and their relation to the change in temporal summation (TS) of pressure pain and self-reported symptoms was evaluated.
Study Design: A controlled, randomized cross-over trial.
Setting: University Hospital Brussels.
Methods: Twenty CFS patients and 20 sedentary healthy controls were included in this study. In both of the groups, the change in TS of pressure pain, CBF (using transcranial Doppler), and HRV (using finger plethysmography) was examined during physical and emotional stress (to control for potential bias), as well as their association mutually and with self-reported symptoms of pain, fatigue, and concentrations difficulties.
Results: There was no significant interaction or group (F-values ranging from .100 to 1.862, P-values ranging from .754 to .181) effect in CBF or HRV parameters. HRV and CBF did change during physical exercise, but the changes did not differ between patients and controls. While pain scores during TS at the trapezius site reduced in the control group after the physical exercise protocol (P=.037), they did not change in the CFS group (P=.108), suggesting impaired pain modulation. There were no significant correlations between CBF, HRV, TS, and self-reported symptoms (all P-values of correlation analyses > .01).
Limitations: Although effect sizes were medium to large, the study sample was relatively low. Also, the mild nature of the exercise bout is discussable. Nonetheless, this mild exercise was able to provoke endogenous pain modulation in the control group, which endorsed a proper execution of the cycling exercise. Moreover, mild exercises are more applicable to daily physical activities in CFS patients than vigorous exercises.
Conclusion: These results seem to refute the previously suggested alterations of CBF/HRV in CFS patients. These cardiovascular parameters appear not to explain pain before, during, and following exercise
The FHI FEL Upgrade Design
Since coming on-line in November 2013, the Fritz-Haber-Institut (FHI) der Max-Planck-Gesellschaft (MPG) Free-Electron Laser (FEL) has provided intense, tunable infrared radiation to FHI user groups. It has enabled experiments in diverse fields ranging from bio-molecular spectroscopy to studies of clusters and nanoparticles, nonlinear solid-state spectroscopy, and surface science, resulting in 50 peer-reviewed publications so far. The MPG has now funded a significant upgrade to the original FHI FEL. A second short Rayleigh range undulator FEL beamline is being added that will permit lasing from 160 microns. Additionally, a 500 MHz kicker cavity will permit simultaneous two-color operation of the FEL from both FEL beamlines over an optical range of 5 to 50 microns by deflecting alternate 1 GHz pulses into each of the two undulators. We will describe the upgraded FHI FEL physics and engineering design and present the plans for two-color FEL operations in November 2020
Synergistic activity of oxaliplatin and 5-fluorouracil in patients with metastatic colorectal cancer with progressive disease while on or after 5-fluorouracil
From February 1995 through October 1996, 25 patients with metastatic colorectal cancer showing a clinical resistance to 5-fluorouracil (5-FU) entered this study. Thirteen received oxaliplatin alone and 12 received it in combination with 5-FU. Oxaliplatin was administered at 130 mg/m(2) over a 2-hour infusion every 3 weeks, alone or added either to 5-FU as a continuous infusion at 200 mg/m(2) to 300 mg/m(2) (six patients) or to a 5-FU bolus, 375 mg/m(2), plus leucovorin, 100 mg/m(2) daily for 5 days every 3 weeks (6 patients).
Eighty-six of 98 administered cycles were evaluable for toxicity (47 for oxaliplatin plus 5-FU and 39 for oxaliplatin alone). Hematologic toxicity was mild, occurring as grade 2 leukopenia in 23% of the cycles of 5-FU and oxaliplatin and in 5% of the cycles of oxaliplatin alone. The most common toxicity was neurologic (grade 1 to 2 in 60%-6% of the cycles of the combination, respectively, and 68%-10% of oxaliplatin given alone) as hand-foot paresthesia or hypersensitivity to cold. No grade 4 toxicity was reported and only three patients in the 5-FU group developed grade 3 diarrhea. Grade 2 nausea and vomiting occurred in 33% of the cycles when both drugs were given and in 15% when oxaliplatin was administered alone.
The combination of oxaliplatin and 5-FU induced four partial remissions (33%; 95% confidence interval, 6%-60%), whereas eight patients of the whole group had stable disease. No response occurred when oxaliplatin was administered as a single agent. The results of this study confirm the antitumor activity of oxaliplatin when added to 5-FU in patients who have metastatic colorectal cancer previously refractory to 5-FU. The possible therapeutic synergy with 5-FU was not accompanied by increased toxicity
The value of competitive employment:In-depth accounts of people with intellectual disabilities
BackgroundIncreasing the societal participation of people with intellectual disabilities via competitive employment requires a full understanding of what this means to them. This paper aims to provide an in‐depth examination of the lived experiences of people with intellectual disabilities in competitive employment.MethodInterviews were conducted with six participants with mild intellectual disability or borderline functioning and good verbal communication skills. Interviews were analysed according to the guidelines of interpretative phenomenological analysis (IPA). Member checks were conducted.ResultsAnalysis yielded three main themes: (a) Building on my life experiences, (b) My place at work and (c) Being a valuable member of society, like everyone else.ConclusionsCompetitive employment could make a substantial contribution to the sense of belonging to society and quality of life of people with intellectual disabilities. Nevertheless, they must cope with stigma‐related obstacles and feelings of being dependent on others in the work environment
In Quest of Neutrino Masses at (eV) Scale
Neutrino oscillation and tritium beta decay experiments taken simultaneously
into account are able to access the so far imperceptible absolute neutrino
masses at the electronvolt level. The neutrino mass spectrum derived in this
way is independent of the nature of neutrinos (Dirac or Majorana). Furthermore,
the lack of neutrinoless double beta decay gives additional constraints on the
Majorana neutrino mass spectrum. A case of three neutrinos is examined.
Influence of different solutions to the solar neutrino deficit problem on the
results is discussed. Apart from the present situation, four qualitatively
distinct experimental situations which are possible in the future are
investigated: when the two decay experiments give only upper bounds on
effective neutrino masses, when either one of them gives a positive result, and
when both give positive results. The discussion is carried out by taking into
account the present experimental errors of relevant neutrino parameters as well
as their much more precise expected estimations (e.g. by factories). It
is shown in which cases the upgraded decay experiments simultaneously with
neutrino oscillation data may be able to fix the absolute scale of the neutrino
mass spectrum, answer the question of the neutrino nature and put some light on
CP phases in the lepton sector.Comment: 30 pages, 6 figs, to appear in PR
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