3,722 research outputs found

    The genus Lycium as food and medicine: A botanical, ethnobotanical and historical review

    Get PDF
    ETHNOPHARMACOLOGICAL RELEVANCE: Lycium is widely distributed in the arid to semi-arid environments of North and South America, Africa, and Eurasia. In recent years, Lycium barbarum and L. chinense have been advertised as "superfood" with healthy properties. Despite of its popularity, there is a lack of an integrated and critical appraisal of the existing evidence for the use of Lycium. AIM OF THE STUDY: There is a need to understand: 1) Which species were used and how the uses of Lycium developed spatially and over time, 2) how uses differ among regions with different culture backgrounds, and 3) how traditional and current therapeutic and preventive health claims correlate with pharmacological findings. METHODS: Information was retrieved from floras, taxonomic, botanical, and ethnobotanical databases, research articles, recent editions of historical Chinese herbals over the last 2000 years, and pharmacopoeias. RESULTS: Of totally 97 species, 31 have recorded uses as food and/or medicine worldwide. Usually the fruits are used. While 85% of the Lycium species occur in the Americas and Africa, 26% of them are used, but 9 out of 14 species in Eurasia. In China, seven species and two varieties of the genus Lycium occur, of which four species have been used by different ethnic groups. Only L. barbarum and L. chinense have been transformed into globally traded commodities. In China, based on the name ", their use can be traced back over the last two millennia. Lycium fruits for anti-aging, improving eyesight and nourishment were documented already in 500C.E. (Mingyi Bielu). Recent findings explain the pharmacological foundations of the traditional uses. Especially polysaccharides, zeaxanthin dipalmitate, vitamins, betaine, and mixed extracts were reported to be responsible for anti-aging, improving eyesight, and anti-fatigue effects. CONCLUSIONS: The integration of historical, ethnobotanical, botanical, phytochemical and pharmacological data has enabled a detailed understanding of Lycium and its wider potential. It highlights that the focus so far has only been on two species and that the genus can potentially yield a wide range of other products with different properties

    The fate of the Deep Western Boundary Current in the South Atlantic

    No full text
    The pathways of recently ventilated North Atlantic Deep Water (NADW) are part of the lower limb of the Atlantic Meridional Overturning Circulation (AMOC). In the South Atlantic these pathways have been the subject of discussion for years, mostly due to the lack of observations. Knowledge of the pathways of the AMOC in the South Atlantic is a first order prerequisite for understanding the fluxes of climatically important properties. In this paper, historical and new observations, including hydrographic and oxygen sections, Argo data, and chlorofluorocarbons (CFCs), are examined together with two different analyzes of the Ocean general circulation model For the Earth Simulator (OFES) to trace the pathway of the recently ventilated NADW through the South Atlantic. CLIVAR-era CFCs, oxygen and salinity clearly show that the strongest NADW pathway in the South Atlantic is along the western boundary (similar to the North Atlantic). In addition to the western boundary pathway, tracers show an eastward spreading of NADW between ~17 and 25°S. Analyzed together with the results of earlier studies, the observations and model output presented here indicate that after crossing the equator, the Deep Western Boundary Current (DWBC) transports water with the characteristics of NADW and a total volume transport of approximately 14Sv (1Sv=106m3s-1). It crosses 5°S as a narrow western boundary current and becomes dominated by eddies further south. When this very energetic eddying flow reaches the Vitória-Trindade Ridge (~20°S), the flow follows two different pathways. The main portion of the NADW flow continues along the continental shelf of South America in the form of a strong reformed DWBC, while a smaller portion, about 22% of the initial transport, flows towards the interior of the basin

    The Road to Quantum Computational Supremacy

    Full text link
    We present an idiosyncratic view of the race for quantum computational supremacy. Google's approach and IBM challenge are examined. An unexpected side-effect of the race is the significant progress in designing fast classical algorithms. Quantum supremacy, if achieved, won't make classical computing obsolete.Comment: 15 pages, 1 figur

    Multi-seeded melt growth (MSMG) of bulk Y-Ba-Cu-O using thin-film seeds

    Full text link
    Y-Ba-Cu-O (YBCO) and Sm-Ba-Cu-O (SmBCO) thin films have been used for the first time as heterogeneous seeds to multi-seed successfully the melt growth of bulk YBCO in a multi-seeded melt growth (MSMG) process. The use of thin film seeds, which may be prepared with highly controlled orientation (i.e. with a well-defined a-b plane and precisely known a-direction), is based on their superheating properties and reduces significantly contamination of the bulk sample by the seed material. A variety of grain boundaries were obtained by varying the angle between the seeds. Microstructural studies indicate that the extent of residual melt deposited at the grain boundary decreases with increasing grain boundary contact angle. It is established that the growth front proceeds continuously at the (110)/(110) grain boundary without trapping liquid, which leads to the formation of a clean grain boundary

    Dopamine Induced Neurodegeneration in a PINK1 Model of Parkinson's Disease

    Get PDF
    Parkinson's disease is a common neurodegenerative disease characterised by progressive loss of dopaminergic neurons, leading to dopamine depletion in the striatum. Mutations in the PINK1 gene cause an autosomal recessive form of Parkinson's disease. Loss of PINK1 function causes mitochondrial dysfunction, increased reactive oxygen species production and calcium dysregulation, which increases susceptibility to neuronal death in Parkinson's disease. The basis of neuronal vulnerability to dopamine in Parkinson's disease is not well understood

    Long-standing Small-scale Reconnection Processes at Saturn Revealed by Cassini

    Get PDF
    The internal mass source from the icy moon Enceladus in Saturn’s rapidly rotating magnetosphere drives electromagnetic dynamics in multiple spatial and temporal scales. The distribution and circulation of the internal plasma and associated energy are thus crucial in understanding Saturn’s magnetospheric environment. Magnetic reconnection is one of the key processes in driving plasma and energy transport in the magnetosphere, and also a fundamental plasma process in energizing charged particles. Recent works suggested that reconnection driven by Saturn’s rapid rotation might appear as a chain of microscale structures, named drizzle-like reconnection. The drizzle-like reconnection could exist not only in the nightside magnetodisk, but also in the dayside magnetodisk. Here, using in situ measurements from the Cassini spacecraft, we report multiple reconnection sites that were successively detected during a time interval longer than one rotation period. The time separation between two adjacently detected reconnection sites can be much less than one rotation period, implying that the reconnection processes are likely small-scale, or frequently repetitive. The spatial distribution of the identified long-standing multiple small reconnection site sequences shows no significant preference on local times. We propose that the small reconnection sites discussed in this Letter are rotationally driven and rotate with the magnetosphere. Since the reconnection process on Saturn can be long-durational, the rotational regime can cause these smallscale reconnection sites to spread to all local times, resulting in global release of energy and mass from the magnetosphere
    • …
    corecore