Millimeter-Wave Diode-Grid Frequency Doubler

Monolithic diode grid were fabricated on 2-cm^2 gallium-arsenide wafers in a proof-of-principle test of a quasi-optical varactor millimeter-wave frequency multiplier array concept. An equivalent circuit model based on a transmission-line analysis of plane wave illumination was applied to predict the array performance. The doubler experiments were performed under far-field illumination conditions. A second-harmonic conversion efficiency of 9.5% and output powers of 0.5 W were achieved at 66 GHz when the diode grid was pumped with a pulsed source at 33 GHz. This grid had 760 Schottky-barrier varactor diodes. The average series resistance was 27 Ω, the minimum capacitance was 18 fF at a reverse breakdown voltage of -3 V. The measurements indicate that the diode grid is a feasible device for generating watt-level powers at millimeter frequencies and that substantial improvement is possible by improving the diode breakdown voltage

Grand canonical partition functions for multi level para Fermi systems of any order

A general formula for the grand canonical partition function for a para Fermi system of any order and of any number of levels is derived.Comment: 9 pages, latex, no figure

Canonical Partition Functions for Parastatistical Systems of any order

A general formula for the canonical partition function for a system obeying any statistics based on the permutation group is derived. The formula expresses the canonical partition function in terms of sums of Schur functions. The only hitherto known result due to Suranyi [ Phys. Rev. Lett. {\bf 65}, 2329 (1990)] for parasystems of order two is shown to arise as a special case of our general formula. Our results also yield all the relevant information about the structure of the Fock spaces for parasystems.Comment: 9 pages, No figures, Revte

The transcription factor Sox5 modulates Sox10 function during melanocyte development

The transcription factor Sox5 has previously been shown in chicken to be expressed in early neural crest cells and neural crest-derived peripheral glia. Here, we show in mouse that Sox5 expression also continues after neural crest specification in the melanocyte lineage. Despite its continued expression, Sox5 has little impact on melanocyte development on its own as generation of melanoblasts and melanocytes is unaltered in Sox5-deficient mice. Loss of Sox5, however, partially rescued the strongly reduced melanoblast generation and marker gene expression in Sox10 heterozygous mice arguing that Sox5 functions in the melanocyte lineage by modulating Sox10 activity. This modulatory activity involved Sox5 binding and recruitment of CtBP2 and HDAC1 to the regulatory regions of melanocytic Sox10 target genes and direct inhibition of Sox10-dependent promoter activation. Both binding site competition and recruitment of corepressors thus help Sox5 to modulate the activity of Sox10 in the melanocyte lineage

School Nurses' Experiences of Health Promotion for School-Age Asylum Seekers

The number of school-age asylum seekers and refugees worldwide is increasing. Health promotion provided by school nurses can be crucial for the well-being of young asylum seekers, yet research on these nurses' experiences is limited. This qualitative study aims to describe school nurses' experiences of providing health promotion to school-age asylum seekers. Semistructured interviews were conducted with 12 school nurses, and inductive content analysis was then used. The results were grouped under the following themes: (1) difficulties in providing health services to school-age asylum seekers, (2) considering the vulnerable circumstances of asylum seekers, (3) the importance of family-centered health promotion, and (4) the importance of time management. School nurses face challenges that stem from individual asylum seekers' unique circumstances, nursing competency, and the school health care system. To deepen the existing knowledge, further research is needed from the perspective of asylum seekers.</p

Ethical issues related to the use of gerontechnology in older people care: A scoping review

Background:Demographic trends indicate growth of population aged 65 and older in Western countries. One of the greatest challenges is to provide high-quality care for all. Technological solutions designed for older people, gerontechnology, can somewhat balance the gap between resources and the increasing demand of healthcare services. However, there are also ethical issues in the use of gerontechnology that need to be pointed out.Purpose:To describe what ethical issues are related to the use of gerontechnology in the care of community-dwelling older people.Methods:A scoping review was performed to identify and analyse studies concerning ethical issues when using gerontechnology in the home care of older people. The literature search was limited to studies published after 1990 and addressed to the electronic databases CINAHL, PubMed, Cochrane, Medic, IEEE Explore and Web of Science. The search was performed in July−August 2018. Data from empirical studies were analysed using thematic analysis.Ethical considerations:This scoping review was conducted in accordance with good scientific practice. The work of other researchers was respected and cited appropriately.Results:A total of 17 studies were identified. Two main themes were found. ‘Balancing between the benefits of using gerontechnology and the basic rights of older people’, consisted of the subthemes safety, privacy and autonomy. The other main theme, ‘Gerontechnology as a risk of insecurity for older people’, included the subthemes fear of losing human contact and concern and fear. Surveillance and monitoring technologies were mainly studied.Conclusion:These results suggest that there may be ethical issues related to the use of gerontechnology and they must therefore be taken into consideration when implementing technology in the care of community-dwelling older people.</div

Ethical issues in the care of patients with stroke: A scoping review

Aims and objectives: The aim was to identify and analyse the ethical issues in the care of patients with stroke (PwS). The goal was to understand the nature of the existing knowledge on the topic and to identify whether there are ethical issues specific to the care of PwS. Background: Stroke is a disease with possible multiple effects on the patient's overall condition and experienced ethical issues in the care. Additionally, stroke impacts the life of the significant other. For health professionals, the care of PwS is challenging at different stages of the care process. The care of stroke includes several ethically sensitive situations from the perspectives of all participants. Design: Scoping review. Methods: The review was conducted following the five-stage methodological framework of Arksey and O'Malley (2005). The literature search was conducted in several electronic databases and complemented with a manual search, resulting in 15 reviewed articles. The analysis was conducted by charting descriptive numerical data and by content analysis of the narrative representations. Results: The studies focused on hospital or rehabilitation contexts and a high number of studies had a qualitative approach. Three main themes were identifiable: “decision-making as an ethically challenging act,” “care process-specific ethical issues” and “environmental ethical issues.”. Conclusions: Ethical issues occur at different stages of the care process of PwS and from the viewpoints of all those involved. However, not all the recognised ethical issues were stroke specific. As the number of the reviewed articles was limited, more research is needed for a comprehensive understanding of the topic. Relevance to clinical practice: Individual health professionals may use the results in observing their own action from an ethical perspective and to deepen the ethical understanding of the care of PwS. In health care organisations, the results may be used in developing the ethical quality of care.</p

Multi-contrast MRI Super-resolution via Implicit Neural Representations

Clinical routine and retrospective cohorts commonly include multi-parametric Magnetic Resonance Imaging; however, they are mostly acquired in different anisotropic 2D views due to signal-to-noise-ratio and scan-time constraints. Thus acquired views suffer from poor out-of-plane resolution and affect downstream volumetric image analysis that typically requires isotropic 3D scans. Combining different views of multi-contrast scans into high-resolution isotropic 3D scans is challenging due to the lack of a large training cohort, which calls for a subject-specific framework.This work proposes a novel solution to this problem leveraging Implicit Neural Representations (INR). Our proposed INR jointly learns two different contrasts of complementary views in a continuous spatial function and benefits from exchanging anatomical information between them. Trained within minutes on a single commodity GPU, our model provides realistic super-resolution across different pairs of contrasts in our experiments with three datasets. Using Mutual Information (MI) as a metric, we find that our model converges to an optimum MI amongst sequences, achieving anatomically faithful reconstruction. Code is available at: https://github.com/jqmcginnis/multi_contrast_inr

Transcription factor Sox10 orchestrates activity of a neural crest-specific enhancer in the vicinity of its gene

The Sox10 transcription factor is a central regulator of vertebrate neural crest and nervous system development. Its expression is likely controlled by multiple enhancer elements, among them U3 (alternatively known as MCS4). Here we analyze U3 activity to obtain deeper insights into Sox10 function and expression in the neural crest and its derivatives. U3 activity strongly depends on the presence of Sox10 that regulates its own expression as commonly observed for important developmental regulators. Sox10 bound directly as monomer to at least three sites in U3, whereas a fourth site preferred dimers. Deletion of these sites efficiently reduced U3 activity in transfected cells and transgenic mice. In stimulating the U3 enhancer, Sox10 synergized with many other transcription factors present in neural crest and developing peripheral nervous system including Pax3, FoxD3, AP2α, Krox20 and Sox2. In case of FoxD3, synergism involved Sox10-dependent recruitment to the U3 enhancer, while Sox10 and AP2α each had to bind to the regulatory region. Our study points to the importance of autoregulatory activity and synergistic interactions for maintenance of Sox10 expression and functional activity of Sox10 in the neural crest regulatory network

Longer wings for faster springs – wing length relates tospring phenology in a long-distanc e migrant across its range

In migratory birds, morphological adaptations for efficient migratory flight often oppose morphological adaptations for efficient behavior during resident periods. This includes adaptations in wing shape for either flying long distances or foraging in the vegetation and in climate-driven variation of body size. In addition, the timing of migratory flights and particularly the timely arrival at local breeding sites is crucial because fitness prospects depend on site-specific phenology. Thus, adaptations for efficient long-distance flights might be also related to conditions at destination areas. For an obligatory long-distance migrant, the common nightingale, we verified that wing length as the aerodynamically important trait, but not structural body size increased from the western to the eastern parts of the species range. In contrast with expectation from aerodynamic theory, however, wing length did not increase with increasing migration distances. Instead, wing length was associated with the phenology at breeding destinations, namely the speed of local spring green-up. We argue that longer wings are beneficial for adjusting migration speed to local conditions for birds breeding in habitats with fast spring green-up and thus short optimal arrival periods. We suggest that the speed of spring green-up at breeding sites is a fundamental variable determining the timing of migration that fine tune phenotypes in migrants across their range