Observations with the
Herschel
Space Telescope have established that most star forming gas is organised in filaments, a finding that is supported by numerical simulations of the supersonic ...interstellar medium (ISM) where dense filamentary structures are ubiquitous. We aim to understand the formation of these dense structures by performing observations covering the
12
CO(4→3),
12
CO(3→2), and various CO(2–1) isotopologue lines of the Musca filament, using the APEX telescope. The observed CO intensities and line ratios cannot be explained by PDR (photodissociation region) emission because of the low ambient far-UV field that is strongly constrained by the non-detections of the C
II
line at 158
μ
m and the O
I
line at 63
μ
m, observed with the upGREAT receiver on SOFIA, as well as a weak C
I
609
μ
m line detected with APEX. We propose that the observations are consistent with a scenario in which shock excitation gives rise to warm and dense gas close to the highest column density regions in the Musca filament. Using shock models, we find that the CO observations can be consistent with excitation by J-type low-velocity shocks. A qualitative comparison of the observed CO spectra with synthetic observations of dynamic filament formation simulations shows a good agreement with the signature of a filament accretion shock that forms a cold and dense filament from a converging flow. The Musca filament is thus found to be dense molecular post-shock gas. Filament accretion shocks that dissipate the supersonic kinetic energy of converging flows in the ISM may thus play a prominent role in the evolution of cold and dense filamentary structures.
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FMFMET, NUK, UL, UM, UPUK
We used laboratory cultures of marine microalgae to investigate the effects of growth conditions and their taxonomic position on the production of isoprene, a gas that has major effects on ...atmospheric chemistry and provides stress tolerance to many primary producers. Isoprene was quantified from 21 microalgal strains sampled during exponential growth, using purge-and-trap pre-concentration and gas chromatography with flame-ionization detection. Isoprene production rates varied by two orders of magnitude between strains (0.03–1.34 μmol g chlorophyll a−1 h−1), and were positively correlated with temperature (r² = 0.52, p < 0.001, n = 59). Three distinct sea surface temperature (SST)–dependent relationships were found between isoprene and chlorophyll a (μmol g chlorophyll a−1 h−1), an improvement in resolution over the single relationship used in previous models: for three polar strains grown at −1°C (slope = 0.03, R² = 0.76, p < 0.05, n = 9), nine strains grown at 16°C (slope = 0.24, R² = 0.43, p < 0.05, n = 27 with Dunaliella tertiolecta excluded), and eight strains grown at 26°C (slope = 0.39, R² = 0.15, p < 0.05, n = 24). We then used a simple model that applied the SST-dependent nature of isoprene production to three representative bioregions for the growth temperatures used in this study. This approach yielded an estimate of global marine isoprene production that was 51% higher than previous attempts using an SST-independent single relationship. Taking into account the effect of temperature therefore potentially allows more precise modeling of marine isoprene production, and suggests that increasing the SST-based resolution of data beyond the three groups used here could further improve future modeling simulations.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Aim
To examine the level of job satisfaction of nurse practitioners/advanced practice nurses in developing and developed countries.
Background
The nurse practitioner/advanced practice nurse has the ...advanced, complex skills and experience to play an important role in providing equitable health care across all nations.
Introduction
Key factors that contribute to health disparities include lack of access to global health human resources, the right skill mix of healthcare providers and the satisfaction and retention of quality workers.
Methods
The study utilized a descriptive analysis and cross‐sectional survey methodology with quantitative and qualitative sections of 1419 job satisfaction survey respondents from an online survey.
Results
Age, number of hours worked in a week and length of time that nurse practitioners/advanced practice nurses worked in their current jobs were statistically significant in job satisfaction. A key barrier was the lack of respect from supervisors and physicians.
Discussion
It was clear from the number of comments in the qualitative section of the survey that having a wide scope of practice is rewarding and challenging to the nurse practitioner and advanced practice nurse.
Conclusion and implications for health policy
The challenges to transform healthcare gaps of access into a better distribution of health care in all countries would constitute a systematic change in policy including providing education and training for doctors and nurses that will match the skills needed in the workplace; emphasizing the right skill mix for the healthcare team; supporting advanced practice nurses in the workplace; and utilizing all healthcare providers to the fullest extent of their abilities.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK, VSZLJ
Genetic testing in the clinic and research lab is becoming more routinely used to identify rare genetic variants. However, attributing these rare variants as the cause of disease in an individual ...patient remains challenging. Here, we report a patient who presented with nephrotic syndrome and focal segmental glomerulosclerosis (FSGS) with collapsing features at age 14. Despite treatment, her kidney disease progressed to end-stage within a year of diagnosis. Through genetic testing, an Y265H variant with unknown clinical significance in alpha-actinin-4 gene (ACTN4) was identified. This variant has not been seen previously in FSGS patients nor is it present in genetic databases. Her clinical presentation is different from previous descriptions of ACTN4 mediated FSGS, which is characterized by sub-nephrotic proteinuria and slow progression to end stage kidney disease. We performed in vitro and cellular assays to characterize this novel ACTN4 variant before attributing causation. We found that ACTN4 with either Y265H or K255E (a known disease-causing mutation) increased the actin bundling activity of ACTN4 in vitro, was associated with the formation of intracellular aggregates, and increased podocyte contractile force. Despite the absence of a familial pattern of inheritance, these similar biological changes caused by the Y265H and K255E amino acid substitutions suggest that this new variant is potentially the cause of FSGS in this patient. Our studies highlight that functional validation in complement with genetic testing may be required to confirm the etiology of rare disease, especially in the setting of unusual clinical presentations.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Zusammenfassung
Der Beitrag rekonstruiert die Coaching-Historie in ihren zentralen Entwicklungslinien Educational Coaching, Sports Coaching, Managerial Coaching und Professional Coaching. Dabei wird ...deutlich, dass Coaching im Ursprung die individuelle ereignisorientierte praxisnahe Befähigung von Menschen mitten in ihrem Aktionsfeld und angesichts hoher Leistungs- bzw. Rollenanforderungen ist. Coaching integrierte erst spät das reflexive Methodenrepertoire aus Counseling und Psychotherapie, was allerdings eine qualitative Wende in der historischen Entwicklung von Coaching bedeutete. Der Beitrag zeigt, dass Coaching ein eigenständiger Mainstream ist, der Elemente aus Beratung, Teaching und Training integriert, ohne einer dieser Disziplinen einverleibt werden zu können.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this work, we studied the interlock requirements in a seed failure scenario for Er
3+
:Yb
3+
doped fiber amplifiers (EYDFAs) pumped with high intensities in the MWcm
−2
range at 9XX nm. We fed a ...time-dependent FEM-tool with the data from backwards directed amplified spontaneous emission (ASE) transients of different commercially available core-pumped single-mode fibers. In the FEM-tool, the Er
3+
:Yb
3+
system is defined as a bi-directional energy transfer process and described by the corresponding rate equations. The power evolution of the pump, seed, and ASE signal is computed by differential equations taking into account the transient population densities of the relevant energy levels. With the model, we computed the temporal evolution of the corresponding energy levels after a seeder failure to take place within tens to hundreds of µs and calculated the associated gain. The fibers under test provide a critical total gain of 30 dB after ∼ 80 µs within the Yb
3+
band and after ∼300 µs within the Er
3+
band. This time decreases with increasing pump power and doping concentration. The results can be extrapolated to high-power cladding-pumped EYDFAs to meet the challenging requirements of engineering-level systems.
Understanding the gain dynamics of fiber amplifiers is essential for the implementation and active stabilization of low noise amplifiers or for coherent beam combining schemes. The gain dynamics of ...purely Er
or Yb
doped fiber amplifiers are well studied, whereas no analysis for co-doped systems, especially for Er
:Yb
co-doped fiber amplifiers has been performed, so far. Here, we analyze for the first time the gain dynamics of Er
:Yb
co-doped fiber amplifiers theoretically and experimentally. It is shown that due to the energy transfer between the Yb
and Er
ions a full analytical solution is not possible. Thus, we used numerical simulations to gain further insights. Comparison of experimental and numerical results shows good qualitative agreement. In addition, we were able to determine the Yb
-Er
transfer function of the energy transfer experimentally.
Isoprene (2-methyl-1,3-butadiene) is emitted in vast quantities (>500 Tg C yr
-1
). Most isoprene is emitted by trees, but there is still incomplete understanding of the diversity of isoprene ...sources. The reactivity of isoprene in the atmosphere has potential implications for both global warming and global cooling, with human health implications also arising from isoprene-induced ozone formation in urban areas. Isoprene emissions from terrestrial environments have been studied for many years, but our understanding of aquatic isoprene emissions is less complete. Several abundant phytoplankton taxa produced isoprene in the laboratory, and the relationship between chlorophyll
a
and isoprene production has been used to estimate emissions from marine environments. The aims of this review are to highlight the role of aquatic environments in the biological cycling of isoprene and to stimulate further study of isoprene metabolism in marine and freshwater environments. From a microbial ecology perspective, the isoprene metabolic gene cluster, first identified in
Rhodococcus
sp. AD45 (
isoGHIJABCDEF
) and subsequently found in every genome-sequenced isoprene-degrader, provides the ideal basis for molecular studies on the distribution and diversity of isoprene-degrading communities. Further investigations of isoprene-emitting microbes, such as the influence of environmental factors and geographical location, must also be considered when attempting to constrain estimates of the flux of isoprene in aquatic ecosystems. We also report isoprene emission by the scleractinian coral
Acropora horrida
and the degradation of isoprene by the same coral holobiont, which highlights the importance of better understanding the cycling of isoprene in marine environments.
We report on theoretical and experimental investigations of gain dynamics in Raman fiber lasers in the frequency range of 1 Hz-1 MHz. An analytical solution of the problem is due to the nonlinear ...nature of the Raman effect not feasible. Thus, we used a numerical simulation to gain general insights. Experimentally and numerically obtained results for a Raman fiber laser emitting at 1180 nm show good qualitative agreement. We also present a potential physical interpretation of the observed dynamical properties. In addition, we report on an experimental proof-of-principle of a passive pump-to-Stokes RIN suppression scheme for the main Stokes order in cascaded Raman fiber lasers utilizing an additional parasitic Stokes order. Again, results from numerical and experimental studies of a cascaded Raman fiber laser at 1180 nm and 1240 nm show good agreement and confirm the passive pump-to-Stokes RIN suppression at 1180 nm. The dependencies between the resonator design and the parameters of the noise suppression are investigated. In addition, it is shown that the scheme can also be applied to cascaded Raman fiber lasers with more then two Stokes shifts. This opens the possibility to design for example low-noise Raman fiber lasers at 1480 nm to pump low-noise Er(3+) doped fiber amplifiers.
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