2,314 research outputs found
In-flight flow visualization with pressure measurements at low speeds on the NASA F-18 high alpha research vehicle
In-flight results from surface and off-surface flow visualizations and from extensive pressure distributions document the vortical flow on the leading edge extensions (LEX) and forebody of the NASA F-18 high alpha research vehicle for low speeds and angles of attack up to 50 degs. Surface flow visualization data, obtained using the emitted fluid technique, were used to define separation lines and laminar separation bubbles. Off-surface flow visualization data, obtained by smoke injection, were used to document both the path of the vortex cores and the location of vortex core breakdown. The location of vortex core breakdown correlated well with the loss of suction pressure on the LEX and with the flow visualization results from ground facilities. Surface flow separation lines on the LEX and forebody corresponded well with the end of pressure recovery under the vortical flows. Correlation of the pressures with wind tunnel results show fair to good correlation
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Preclinical translation of exosomes derived from mesenchymal stem/stromal cells.
Exosomes are nanovesicles secreted by virtually all cells. Exosomes mediate the horizontal transfer of various macromolecules previously believed to be cell-autonomous in nature, including nonsecretory proteins, various classes of RNA, metabolites, and lipid membrane-associated factors. Exosomes derived from mesenchymal stem/stromal cells (MSCs) appear to be particularly beneficial for enhancing recovery in various models of disease. To date, there have been more than 200 preclinical studies of exosome-based therapies in a number of different animal models. Despite a growing number of studies reporting the therapeutic properties of MSC-derived exosomes, their underlying mechanism of action, pharmacokinetics, and scalable manufacturing remain largely outstanding questions. Here, we review the global trends associated with preclinical development of MSC-derived exosome-based therapies, including immunogenicity, source of exosomes, isolation methods, biodistribution, and disease categories tested to date. Although the in vivo data assessing the therapeutic properties of MSC-exosomes published to date are promising, several outstanding questions remain to be answered that warrant further preclinical investigation
Summary of in-flight flow visualization obtained from the NASA high alpha research vehicle
A summary of the surface and off-surface flow visualization results obtained in flight on the F-18 high alpha research vehicle (HARV) is presented, highlighting the extensive 3-D vortical flow on the aircraft at angles of attack up to 50 degs. The emitted fluid technique, as well as tufts and flow cones, were used to document the surface flow. A smoke generator system injected smoke into the vortex cores generated by the forebody and leading edge extensions (LEXs). Documentation was provided by onboard still and video, by air-to-air, and by postflight photography. The surface flow visualization techniques revealed laminar separation bubbles near the forebody apex, lines of separation on the forebody and LEX, and regions of attached and separated flow on the wings and fins. The off-surface flow visualization techniques showed the path of the vortex cores on the forebody and LEX as well as the LEX vortex core breakdown location. An interaction between the forebody and LEX vortices was noted. The flow over the surfaces of the vertical tail was categorized into regions of attached, unsteady, or separated flow using flow tufts
The Economic Lifecycle by Gender – Results Combining Monetary and Time Use Estimates
In recent decades, we have witnessed profound changes in family size and structure. While marriage rates and the number of children have declined in most industrialised countries, female labour force participation rates have risen significantly. However, while the working hours and wages of women have increased, we continue to observe huge discrepancies in market production by gender in Germany. This results in considerable differences in the economic lifecycle of men and women. The differences diminish if we take unpaid household production, consumption, and caring into account. We find that, after applying this comprehensive approach, the female lifecycle resembles male consumption, income, and transfer patterns. These findings are interesting in the light of future demographic changes, as they suggest that the explicit policy aim of increasing female labour force participation could place constraints on the currently observed division of labour in the market and in the household.In recent decades, we have witnessed profound changes in family size and structure. While marriage rates and the number of children have declined in most industrialised countries, female labour force participation rates have risen significantly. However, while the working hours and wages of women have increased, we continue to observe huge discrepancies in market production by gender in Germany. This results in considerable differences in the economic lifecycle of men and women. The differences diminish if we take unpaid household production, consumption, and caring into account. We find that, after applying this comprehensive approach, the female lifecycle resembles male consumption, income, and transfer patterns. These findings are interesting in the light of future demographic changes, as they suggest that the explicit policy aim of increasing female labour force participation could place constraints on the currently observed division of labour in the market and in the household
Perbedaan Tingkat Religiusitas dan Sikap terhadap Seks Pranikah antara Pelajar yang Bersekolah di SMA Umum dan SMA Berbasis Agama
Fenomena seks pranikah yang terjadi di masyarakat sekarang sudah menjalar di kalangan pelajar SMP dan SMA. Minimnya pendidikan agama di sekolah dinilai menjadi salah satu faktor pemicu tingginya angka praktik seks pranikah pada remaja di Indonesia karena pendidikan agama dapat meningkatkan tingkat religiusitas pada remaja. Tingkat religiusitas dapat memunculkan sikap mendukung atau tidak mendukung terhadap seks pranikah Daradjat (dalam Ritandiyono & Andisti, 2008). Praktik pendidikan agama di Indonesia saat ini hanya mengutamakan aspek kognitif dan mengabaikan aspek afektif dan konatif-volitif yaitu kemauan untuk mengamalkan, sehingga terjadi kesenjangan antara pengetahuan tentang agama yang dimiliki dengan pengamalan ajaran agama yang telah diterima (Bukhori, dalam Lobud 2007). Di Indonesia, terdapat dua tipe sekolah yaitu sekolah umum dan sekolah berbasis agama. Perbedaan dari dua sekolah ini adalah pada sekolah berbasis agama tidak hanya menitikberatkan pada pengetahuan namun juga menitikberatkan pada peningkatan keimanan serta ketaqwaan.Penelitian ini bertujuan untuk mengetahui apakah ada perbedaan tingkat religiusitas dan sikap terhadap seks pranikah pada pelajar yang bersekolah di SMA umum dan SMA berbasis agama.Penelitian dilakukan pada 396 pelajar, yang terdiri dari 198 pelajar yang SMA umum dan 198 pelajar SMA berbasis agama. Teknik pengumpulan data menggunakan angket tingkat religiusitas dan angket sikap terhadap seks pranikah. Pengujian hipotesis dilakukan menggunakan statistik non parametrik U Mann Whitney.Hasil penelitian menunjukkan bahwa tidak ada perbedaan tingkat religiusitas antara pelajar di SMA umum dan SMA berbasis agama dengan nilai p=0,257 (> 0,05). Sedangkan pengujian hipotesis kedua menunjukkan bahwa ada perbedaan sikap terhadap seks pranikah antara pelajar SMA umum dan SMA berbasis agama dengan p = 0,000 (< 0,05). Hal ini menunjukkan bahwa perlunya pendidikan seksual yang tidak hanya berdasarkan pendidikan agama, namun juga dengan memberikan muatan-muatan informasi seputar seksualitas yang akurat serta pemberian pendidikan agama yang dapat menyelaraskan aspek kognitif dan afektif pelajar dengan metode pembelajaran yang menuntut pelajar untuk aktif, kreatif, mandiri dan menyenangka
Fanny Copeland and the geographical imagination
Raised in Scotland, married and divorced in the English south, an adopted Slovene, Fanny Copeland (1872 – 1970) occupied the intersection of a number of complex spatial and temporal conjunctures. A Slavophile, she played a part in the formation of what subsequently became the Kingdom of Yugoslavia that emerged from the First World War. Living in Ljubljana, she facilitated the first ‘foreign visit’ (in 1932) of the newly formed Le Play Society (a precursor of the Institute of British Geographers) and guided its studies of Solčava (a then ‘remote’ Alpine valley system) which, led by Dudley Stamp and commended by Halford Mackinder, were subsequently hailed as a model for regional studies elsewhere. Arrested by the Gestapo and interned in Italy during the Second World War, she eventually returned to a socialist Yugoslavia, a celebrated figure. An accomplished musician, linguist, and mountaineer, she became an authority on (and populist for) the Julian Alps and was instrumental in the establishment of the Triglav National Park. Copeland’s role as participant observer (and protagonist) enriches our understanding of the particularities of her time and place and illuminates some inter-war relationships within G/geography, inside and outside the academy, suggesting their relative autonomy in the production of geographical knowledge
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Complement protein levels in plasma astrocyte-derived exosomes are abnormal in conversion from mild cognitive impairment to Alzheimer's disease dementia.
IntroductionLevels of complement proteins (CPs) in plasma astrocyte-derived exosomes (ADEs) that are abnormal in Alzheimer's disease (AD) have not been assessed in mild cognitive impairment (MCI).MethodsParticipants (n = 20 per group) had either MCI converting to dementia within 3 years (MCIC), MCI remaining stable over 3 years (MCIS), Alzheimer's disease, or were controls. CPs of ADEs isolated from plasmas by anti-human glutamine aspartate transporter antibody absorption were quantified by ELISAs.ResultsADE levels of C1q and C4b of the classical pathway, factor D and fragment Bb of the alternative pathway, and C5b, C3b, and C5b-C9 of both pathways were significantly higher in patients with MCIC than those with MCIS. ADE levels of inhibitory CPs decay-accelerating factor, CD46, CD59, and type 1 complement receptor were significantly lower in patients with MCIC than those with MCIS.DiscussionADE CPs are components of neurotoxic neuroinflammation that may be predictive biomarkers of MCI conversion to Alzheimer's disease
Anomalous direction for skyrmion bubble motion
Magnetic skyrmions are localized topological excitations that behave as
particles and can be mobile, with great potential for novel data storage
devices. In this work, the current-induced dynamics of large skyrmion bubbles
is studied. When skyrmion motion in the direction opposite to the electron flow
is observed, this is usually interpreted as a perpendicular spin current
generated by the spin Hall effect exerting a torque on the chiral N\'{e}el
skyrmion. By designing samples in which the direction of the net generated spin
current can be carefully controlled, we surprisingly show that skyrmion motion
is always against the electron flow, irrespective of the net vertical
spin-current direction. We find that a negative bulk spin-transfer torque is
the most plausible explanation for the observed results, which is qualitatively
justified by a simple model that captures the essential behaviour. These
findings demonstrate that claims about the skyrmion chirality based on their
current-induced motion should be taken with great caution
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