scholarly journals Hayabusa2’s Superior Solar Conjunction Phase

2020 ◽  
Vol 216 (6) ◽  
Author(s):  
Stefania Soldini ◽  
Tomohiro Yamaguchi ◽  
Yuichi Tsuda ◽  
Saiki Takanao ◽  
Satoru Nakazawa
Keyword(s):  
Covariance Analysis ◽  
Communication Link ◽  
Home Position ◽  
The Earth ◽  
Before And After ◽  
Wide Angle Camera ◽  
Navigation Planning ◽  
The Hill ◽  
First Time ◽  
Full Body

Abstract Hayabusa2 is the ongoing JAXA’s sample and return mission to the asteroid Ryugu. In late 2018, Ryugu was in superior solar conjunction with the Earth. It is the first time that a spacecraft experiences the blackouts in the communication link with the Earth while hovering around a small celestial body. In this article, the design of the nominal conjunction trajectory flown by the Hayabusa2’s spacecraft is presented. The requirements for the conjunction trajectory were (1) to guarantee a low fuel consumption, (2) to ensure the visibility of the asteroid by the spacecraft’s wide angle camera ($60^{\circ }$ 60 ∘ FoV), and (3) to increase the spacecraft altitude to a safety location ($\sim109~\mbox{km}$ ∼ 109 km ) from the nominal BOX-A operation of 20 km (Home Position - HP). Finally, (4) to return at BOX-A after the conjunction phase. Given the mission constraints, the designed conjunction trajectory appears to have a fish-shape in the Hill coordinates therefore we renamed it as “ayu” (sweetfish in Japanese) trajectory. The optNEAR tool was developed for the guidance ($\Delta V\mbox{s}$ Δ V s planning) and navigation design of the Hayabusa2’s conjunction mission phase. A preliminary sensitivity analysis in the Hill reference frame proved that the ayu trajectory is a good candidate for the conjunction operation of hovering satellite. The solution in the Hill coordinates is refined in the full-body planetary dynamics (optNEAR Tool) before flight. The ayu conjunction trajectory requires (a) two deterministic $\Delta V\mbox{s}$ Δ V s at the Conjunction Orbit Insertion (COI) point and at the Home-position Recovery Maneuver (HRM) point respectively. (b) Two stochastic $\Delta V\mbox{s}$ Δ V s , known as Trajectory Correction Manoeuvres (TCMs), before and after the deep conjunction phase are also required. The constraint linear covariance analysis in the full-body dynamics is here derived and used for the preliminary guidance and navigation planning. The results of the covariance analysis were validated in a nonlinear sense with a Monte Carlo approach which proved the validity of the semi-analytic method for the stochastic $\Delta V\mbox{s}$ Δ V s planning derived in this paper.

scholarly journals Hayabusa2’s superior solar conjunction mission operations: planning and post-operation results

Astrodynamics ◽  
2020 ◽  
Vol 4 (4) ◽  
pp. 265-288 ◽  
Author(s):  
Stefania Soldini ◽  
Hiroshi Takeuchi ◽  
Sho Taniguchi ◽  
Shota Kikuchi ◽  
Yuto Takei ◽  
...  
Keyword(s):  
Communication Link ◽  
Time Data ◽  
Operations Planning ◽  
The Earth ◽  
Post Operation ◽  
A Minor ◽  
Operation Results ◽  
The Hill ◽  
First Time ◽  
Mission Operations

AbstractIn late 2018, the asteroid Ryugu was in the Sun’s shadow during the superior solar conjunction phase. As the Sun-Earth-Ryugu angle decreased to below 3°, the Hayabusa2 spacecraft experienced 21 days of planned blackout in the Earth-probe communication link. This was the first time a spacecraft had experienced solar conjunction while hovering around a minor body. For the safety of the spacecraft, a low energy transfer trajectory named Ayu was designed in the Hill reference frame to increase its altitude from 20 to 110 km. The trajectory was planned with the newly developed optNEAR tool and validated with real time data. This article shows the results of the conjunction operation, from planning to flight data.

Untersuchungen zur Quantifizierung der Änderung der Skelettmuskeldurchblutung nach Gefäßrevaskularisationen mit einem 99mTechnetiummarkierten Tracer

1990 ◽  
Vol 29 (05) ◽  
pp. 215-220 ◽  
Author(s):  
R. Benning ◽  
K. Nagel ◽  
M. Jugenheimer ◽  
S. Fischer ◽  
S. Worthmann ◽  
...  
Keyword(s):  
Transluminal Angioplasty ◽  
Lower Limbs ◽  
Surgical Patients ◽  
Treadmill Test ◽  
Negative Results ◽  
Clinical Observations ◽  
Before And After ◽  
Comparative Results ◽  
First Time ◽  
Percutaneous Transluminal

A new 99mTc-labelled tracer (99mTc-Sestanriibi) was used for the first time to demonstrate the perfusion of the skeletal muscle. In 16 patients with obstructive atherosclerosis of the lower limbs the change of perfusion of thigh and lower leg was studied with SPECT before and after vascular surgery (n = 11) or percutaneous transluminal angioplasty (n = 5). Comparative results of scintigraphic measurements and clinical observations (ancle-arm pressure, treadmill test) in 10 surgical patients (14 operated legs) showed correct positive or negative results in 86% (12/14).

Trombodynamics Method in the Assessment of Coagulation Parameters in Psychopharmacotherapy of Endogenous Mental Disorders

Psychiatry ◽  
2020 ◽  
Vol 18 (4) ◽  
pp. 16-25
Author(s):  
N. S. Karpova ◽  
O. S. Brusov ◽  
I. V. Oleichik ◽  
M. I. Faktor ◽  
N. S. Levchenko ◽  
...  
Keyword(s):  
Mental Disorders ◽  
Response To Therapy ◽  
Procoagulant Activity ◽  
Coagulation Activity ◽  
Continuous Type ◽  
Chronic Neuroinflammation ◽  
Psychopharmacological Treatment ◽  
Before And After ◽  
First Time ◽  
Schizotypal Disorder

Background: currently, it has been proven that the pathogenesis of endogenous mental disorders is associated with the process of neuroinflammation in the brain of patients. It is also known that chronic neuroinflammation, accompanied by a violation the permeability of the blood-brain barrier. It is accompanied by the activation of platelets that generate procoagulant microparticles, which leads to a disturbance of the hemostasis system, causing an increase in blood clotting in patients. Objective: to investigate the dynamics of procoagulant activity of blood in patients with endogenous mental disorders before and after psychopharmacotherapy.Patients and methods: the study included 185 patients aged 16 to 64 years with the following mental disorders: schizophrenia with attack-like/attack-progressive/continuous type of course (F20.00–2), affective disease (F31.1–5; F32.0–3; F33.0–3), schizotypal disorder with affective fluctuations (F21.3–4). The thrombodynamic test (TD) was performed on T-2 Trombodynamis device according to the manufacturer’s instructions (Hemacore LLC, Moscow, Russia). All patients received standard pharmacotherapy according to their condition.Results: a significant decrease of procoagulant activity of spontaneous clots in the patients’ blood after psychopharmacological treatment is observed. Our data on the positive dynamics of changes in the values of TD test’s indicators in most of the examined patients suggest that a decrease in the coagulation activity of the patients’ blood as a result of treatment may be associated with the anti- inflammatory effect of antipsychotics and antidepressants.Conclusion: for the first time, it was shown that there is a positive dynamic in changing the values of the main parameters of the TD test in most patients with endogenous mental diseases. The results of TD tests can be the basis for monitoring the response to therapy.

scholarly journals Experiential ownership and body ownership are different phenomena

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Caleb Liang ◽  
Wen-Hsiang Lin ◽  
Tai-Yuan Chang ◽  
Chi-Hong Chen ◽  
Chen-Wei Wu ◽  
...  
Keyword(s):  
Conscious Experience ◽  
Distinct Type ◽  
Body Part ◽  
The Body ◽  
Body Ownership ◽  
Rubber Hand ◽  
Person Perspective ◽  
The One ◽  
First Time ◽  
Full Body

AbstractBody ownership concerns what it is like to feel a body part or a full body as mine, and has become a prominent area of study. We propose that there is a closely related type of bodily self-consciousness largely neglected by researchers—experiential ownership. It refers to the sense that I am the one who is having a conscious experience. Are body ownership and experiential ownership actually the same phenomenon or are they genuinely different? In our experiments, the participant watched a rubber hand or someone else’s body from the first-person perspective and was touched either synchronously or asynchronously. The main findings: (1) The sense of body ownership was hindered in the asynchronous conditions of both the body-part and the full-body experiments. However, a strong sense of experiential ownership was observed in those conditions. (2) We found the opposite when the participants’ responses were measured after tactile stimulations had ceased for 5 s. In the synchronous conditions of another set of body-part and full-body experiments, only experiential ownership was blocked but not body ownership. These results demonstrate for the first time the double dissociation between body ownership and experiential ownership. Experiential ownership is indeed a distinct type of bodily self-consciousness.

Alexander and the Mongols

1979 ◽  
Vol 111 (2) ◽  
pp. 123-136 ◽  
Author(s):  
John Andrew Boyle
Keyword(s):  
Eighth Century ◽  
Alexander The Great ◽  
The Caucasus ◽  
The North ◽  
The Earth ◽  
Four Corners ◽  
Book Of Genesis ◽  
First Time

The association of Alexander the Great with the Mongols begins with the identification of the latter with the peoples of Gog and Magog. The evolution of this legend, which has its origin in the Book of Genesis, is curious in the extreme. In Genesis Magog is mentioned as one of the sons of Japhet, his name occurring between those of Gomer and Madai. Since Madai is clearly intended as the eponym of the Medes and Gomer has been located in Cappadocia and Phrygia it has been plausibly suggested that Magog at this stage corresponded to the territory in between, i.e. the region immediately south of the Caucasus in Eastern and Northern Armenia. In Ezekiel we hear for the first time of Gog “of the land of Magog”, who will come from his place out of the uttermost parts of the north, he and many peoples with him, “all of them riding on horses, a great company and a mighty army.” It will be seen that the “land of Magog” can no longer be located south of the Caucasus, and indeed Ezekiel's prophecy of the invasion of Gog has been interpreted as an echo of the invasions of the Cimmerians, who came southwards from the steppes through the Darial pass towards the end of the eighth century B.C.; or more probably of the invasion of the Scythians which took place in the following century by way of Darband. Finally we are told in Revelation that “when the thousand years are finished, Satan shall be loosed out of his prison, and shall come forth to deceive the nations which are in the four corners of the earth, Gog and Magog, to gather them together to the war; the number of whom is as the sand of the sea”.

scholarly journals Influences of the selected additives on the weight loss and organoleptic properties of marinated mussels and squids

2012 ◽  
Vol 81 (3) ◽  
pp. 263-267 ◽  
Author(s):  
Metin Guldas ◽  
Canan Hecer
Keyword(s):  
Weight Loss ◽  
Salt Content ◽  
Meat Products ◽  
Organoleptic Properties ◽  
Highest Weight ◽  
Konjac Flour ◽  
Weight Gains ◽  
Before And After ◽  
Mouth Feel ◽  
First Time

Effects of seven different solutions prepared from various additives (carrageenan, konjac flour, phosphate, yeast extract, xanthan gum and maltodextrin) were used to test for the first time in the marination of experimental seafood. The additives were added into the marination solutions and the samples were analyzed before and after marination. Statistically, the experimental solutions did not cause significant changes in pH, acidity and salt content of the samples (P < 0.05). The highest weight gains were obtained from the solution which contained 0.1% of konjac flour (E425 I) as 4.01, 5.21, 4.61 and 4.88 % in the mussels, big squids, diced squids and small squids, respectively. However, this solution was not preferred by the panellists because of its sticky texture. Inversely to red meat products, the solution containing phosphate caused weight loss during marination. The results indicate that the solution containing 0.2% carrageenan LM (low methoxyl) was the best solution in the marination process. Dipping into this solution caused weight gains of 4.69, 2.98, 4.04 and 2.78% in the big squids, the mussels, the small squids and the diced squids, respectively (P < 0.01). The organoleptic properties (mouth feel, flavour and softness) of mussels and squids were also improved by carrageenan LM addition.

The effects of dehydration and local soil on parasite recovery: A preliminary paleoparasitological evaluation on experimental coprolites

The Holocene ◽  
2021 ◽  
pp. 095968362110499
Author(s):  
Darío Alejandro Ramirez ◽  
Mariana Fabra ◽  
Samanta Xavier ◽  
Alena Mayo Iñiguez
Keyword(s):  
Equal Mass ◽  
Central Argentina ◽  
Soil Sediment ◽  
Local Soil ◽  
Before And After ◽  
Fresh Feces ◽  
Flotation Technique ◽  
First Time ◽  
Taphonomic Processes

Experimental paleoparasitological approaches have been used in order to optimize the methodology previously to the application in archeological samples. In this study we evaluated the action of dehydration and local soil (Central Argentina) on the loss of parasite eggs in experimental coprolites, using two parasitological techniques: spontaneous sedimentation and sucrose-flotation. Experimental coprolites comprised fresh human feces, positive for Hymenolepis nana, Ascaris sp., and Enterobius vermicularis, submitted to controlled artificial dehydration. Experimental coprolites with soil addition were prepared by mixing archeological sediment with equal mass of fresh feces. Helminth eggs were counted and eggs per gram were estimated in each subsample. Statistical analyses were applied to compare subsamples before and after desiccation and with and without addition of soil sediment. The performance of parasitological methods statistically differed, the sucrose flotation technique being the less effective when fresh feces and experimental coprolites were analyzed. Partial deformation of eggs was observed via both techniques only in subsamples containing H. nana eggs. However, this was not seen in Ascaris sp. subsamples, possibly due to eggshell composition. We found that sample desiccation significantly decreased the number of eggs in the experimental coprolites. Mixing archeological sediment with the fecal material also resulted in significantly fewer eggs surviving, independent of desiccation. This shows that climate and soil in which archeological fecal samples are found can strongly influence the survival of parasite eggs from past populations. The small amount of parasite evidence often found in paleoparasitological analyses, including Central Argentina, could be attributed to the action of taphonomic processes rather than to the real absence of infection in these ancient populations. Importantly, the study highlights the role of local soil, confirmed for the first time by empirical data. The research provides valuable insights into the understanding of the paleoparasitological results of the region and of general paleoparasitology.

On the Electrochemical Insertion of Mg2+in Na7V4(P2O7)4(PO4) and Na3V2(PO4)3 Host Materials

2021 ◽  
Author(s):  
Saustin Dongmo ◽  
Fabio Maroni ◽  
Cornelius Gauckler ◽  
Mario Marinaro ◽  
Margret Wohlfahrt-Mehrens
Keyword(s):  
Energy Storage ◽  
Research And Development ◽  
Cathode Materials ◽  
Fast Kinetics ◽  
The Earth ◽  
Host Materials ◽  
High Potentials ◽  
Phosphate Phase ◽  
Storage Technologies ◽  
First Time

Abstract Next generation energy storage technologies need to be more sustainable and cheaper. Among Post-Li chemistries, Mg batteries are emerging as a possible alternative with desirable features like abundance of Mg on the Earth`s crust and a doubled volumetric capacity with respect to the current Li metal. However, research and development of Mg-batteries is still in its infancy stage and still many hurdles are to be understood and solved. For instance, cathode materials showing high capacities, operating at high potentials and with sufficient fast kinetics need to be designed and developed. Polyanionic materials are a class of sustainable and environmentally friendly materials that emerged as possible Mg2+ hosts. In this work the insertion of Mg cations inside the NASICON Na3V2(PO4)3 and, for the first time, in the mixed phosphate phase Na7V4(P2O7)4(PO4), is reported, structurally and electrochemically characterized.

“Girls Are Like Flowers; Boys Are Like footballs”

2021 ◽  
Vol 14 (1) ◽  
pp. 45-62
Author(s):  
Florencia Herrera
Keyword(s):  
Longitudinal Study ◽  
Hegemonic Masculinity ◽  
Before And After ◽  
Gender Practices ◽  
First Time ◽  
Masculine Gender

To contribute to the discussion about how masculinity—understood as a configuration of gender practices (Connell 2000)—is reproduced, this paper analyzes fathers’ discourse about the gender of their sons and daughters. I carried out a qualitative longitudinal study in Chile during which 28 first-time fathers were interviewed before and after their child’s birth or arrival (adoption). I suggest that these fathers see gender in essentialist, dichotomous, and hierarchical terms. They expect to shape their sons’ gender practices according to hegemonic masculinity (discouraging gender practices associated with femininity or homosexuality). In the study, no attempt to reformulate masculine gender practices was observed but, rather, an interest on the fathers’ part in maintaining the patriarchal gender order.

Cosmic Deer as an Archaic Symbol in the Narratives and Rituals of the Tungus-Manchus

2020 ◽  
pp. 112-121
Author(s):  
Татьяна Юрьевна Сем
Keyword(s):  
Bronze Age ◽  
The Sun ◽  
Time Model ◽  
Space And Time ◽  
The Earth ◽  
Cosmic Scale ◽  
First Time ◽  
The Universe ◽  
The Bronze Age

Статья посвящена мифологическому образу космического оленя в традиционной культуре тунгусо-маньчжуров. В работе рассматриваются материалы фольклора, шаманства, промысловых и календарных ритуалов, а также искусства. Впервые систематизированы материалы по всем тунгусо-маньчжурским народам. Образ космического оленя в фольклоре эвенов имеет наиболее близкие аналогии с амурскими народами, которые представляют его с рогами до небес. Он сохранился в сказочном фольклоре с мифологическими и эпическими элементами. В эвенском мифе образ оленя имеет космические масштабы: из тела его происходит земля и всё живущее на ней. У народов Амура образ оленя нашел отражение в космогенезе, отделении неба от земли. Своеобразие сюжета космической охоты характеризует общесибирскую мифологию, относящуюся к ранней истории. В ней наиболее ярко проявляется мотив смены старого и нового солнца, хода времени, смены времен года, календарь тунгусо-маньчжуров. В результате анализа автор пришел к выводу, что олень в тунгусо-маньчжурской традиции моделирует пространство и время Вселенной, характеризует образ солнца и хода времени. Космический олень является архетипичным символом культуры тунгусо-маньчжуров, сохранившим свое значение до настоящего времени в художественной культуре This article is devoted to the mythological image of cosmic deer in traditional Tungus-Manchu culture. It examines materials of folklore, shamanism, trade and calendar rituals as well as art and for the first time systematizes materials from all of the Tungus-Manchu peoples. The image of cosmic deer in the folklore of the Evens has its closest analogy in that of the Amur peoples, reflected in the image of a deer with horns reaching up to the sky. This image is preserved in fairytales with mythological and epic elements. In the Even myth, the image of a deer is on a cosmic scale, as the cosmos issues from its body. Among the Amur peoples, the image of a deer is also related to cosmogenesis, to the separation of the earth from the sky. The plot of a cosmic hunt is reflected in pan-Siberian mythology, dating back to the Bronze Age. It clearly illustrates the motif of the change of the old and new sun, the passage of time, the change of seasons, the Tungus-Manchu calendar. The author comes to the conclusion that deer in the Tungus-Manchu tradition, in depicting the image of the sun and the passage of time, model the space and time of the Universe. The cosmic deer is an archetypal symbol of Tungus-Manchu culture, which has retained its significance in artistic culture to the present day.

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