European Student Moon Orbiter (ESMO)

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Low-thrust trajectories design for the European Student Moon Orbiter mission

Low-thrust trajectories design for the European Student Moon Orbiter mission

The following paper presents the mission analysis studies performed for the phase A of the solar electric propulsion option of the European Student Moon Orbiter (ESMO) mission. ESMO is scheduled to be launched in 2011, as an auxiliary payload on board of Ariane 5. Hence the launch date will be imposed by the primary payload. A method to efficiently assess wide launch windows for the Earth-Moon transfer is presented here. Sets of spirals starting from the GTO were propagated forward with a continuous tangential thrust until reaching an apogee of 280,000 km. Concurrently, sets of potential Moon spirals were propagated backwards from the lunar orbit injection. The method consists of ranking all the admissible lunar spiral-down orbits that arrive to the target orbit with a simple tangential thrust profile after a capture through the L 1 Lagrange point. The ‘best’ lunar spiral is selected

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European Student Moon Orbiter solar electric propulsion
subsystem architecture: an all–electric spacecraft

European Student Moon Orbiter solar electric propulsion subsystem architecture: an all–electric spacecraft

This paper presents the Phase A study of the Solar Electric Propulsion subsystem selected for the ESA European Student Moon Orbiter enhanced microsatellite, performed at QinetiQ under ESA funding. To minimise mass, a so-called "all electric" approach is adopted based around the re-use of the GOCE T5 gridded ion engine and the introduction of Hollow Cathode Thrusters (HCTs) for attitude control functions. Three different subsystem architectures are considered and analyzed with reference to the mass, cost, risk and level of integration between the HCTs and the T5. The favoured system architecture that best meets the various requirements adopts a shared tank and gas flow controller between the HCTs and the T5, with power being supplied from two dedicated power processing units. The possibility of reducing the propellant requirement by using an engine gimbal mechanism is also presented. The study also demonstrates how an increase in the T5 specific impulse to higher values than used on GOCE does not offer substantial system-level mass savings in this particular case.

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Orbit determination and control for the European Student Moon Orbiter

Orbit determination and control for the European Student Moon Orbiter

This paper presents the preliminary navigation and orbit determination analyses for the European Student Moon Orbiter. The severe constraint on the total mission D v and the all-day piggy-back launch requirement imposed by the limited available budget, led to the choice of using a low-energy transfer, more specifically a Weak Stability Boundary one, with a capture into an elliptic orbit around the Moon. A particular navigation strategy was devised to ensure capture and fulfil the requirement for the uncontrolled orbit stability at the Moon. This paper presents a simulation of the orbit determination process, based on an extended Kalman filter, and the navigation strategy applied to the baseline transfer of the 2011–2012 window. The navigation strategy optimally allocates multiple Trajectory Correction Manoeuvres to target a so-called capture corridor. The capture corridor is defined, at each point along the transfer, by back-propagating the set of perturbed states at the Moon that provides an acceptable lifetime of the lunar orbit.

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Navigation analysis and manoeuvres design for the European Student Moon Orbiter

Navigation analysis and manoeuvres design for the European Student Moon Orbiter

The motivation for this analysis is to obtain an estimation of the required orbit determination accuracy. The first step is to derive a requirement for the accuracy of the determination of the lunar orbit injection point. An error in the determination of the injection point would translate into a potentially different orbit around the Moon. A different orbit will imply either a longer or shorter lifetime. Therefore, the first analysis will estimate the lifetime of the orbit around the Moon given an error in the initial conditions of the orbital elements. A second analysis will investigate the required accuracy at different times along the transfer orbit. The required accuracy in orbit determination must be such that one can correctly predict if ESMO will be captured around the Moon in an orbit with the desired lifetime. From the first analysis, a requirement on the insertion accuracy is derived. At the injection point, the insertion accuracy is given as a function of the error in position and velocity. This error is then propagated backwards. The set of back-propagated states defines a region (or cloud) in the state space that surrounds the nominal solution. Each point inside the cloud represents a pair of position and velocity that will lead to capture if the state is propagated forward. The orbit determination accuracy must be such that it can estimate, with 99% probability, that ESMO is within the cloud. The cloud will be called capture corridor in the remainder of this paper.

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Orbit determination and control for the European Student Moon Orbiter

Orbit determination and control for the European Student Moon Orbiter

10 m/s and represent only the projection of the corridor on the r-h plane. Similar figures can be obtained by projecting the corridor on the r-t plane. The trajectories corresponding to the curl will not reach the WSB region and do not represent feasible transfers. Furthermore, it is important to note how the corridor tends to get thinner in the normal and transversal directions while it seems to stretch along the radial direction. Based on the propagation of the corridor, and considering the required accuracy of position and velocity at the farthest point from the Earth (WSB region), along the transfer trajectory, it was possible to derive the orbit determination accuracy. This is reported in Table 2 and details the measured accuracy of the range (position) and velocity of ESMO relative to the ground stations. All

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Characteristics and prognostic factors of colorectal mucinous adenocarcinoma with signet ring cells

Characteristics and prognostic factors of colorectal mucinous adenocarcinoma with signet ring cells

AJCC, American Joint Committee on Cancer; CI, confidence interval; ESMO, European Society for Medical Oncol- ogy; H&E, hematoxylin and eosin; HR, hazard ratio; IHC, immunohistochemical; LVI, lymphovascular invasion; MAC, mucinous adenocarcinoma; MAC-SRC, MAC with SRCs; OS, overall survival; PFS, progression-free survival; Post-CT, postoperative chemotherapy; Post-RT, postoperative radio- therapy; Pre-CEA, preoperative carcinoembryonic antigen; Pre-CT, preoperative chemotherapy; Pre-RT, preoperative radiotherapy; SRC, signet ring cell; SRCC, signet ring cell carcinoma; VI, vascular invasion

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Career opportunities and benefits for young oncologists in the European Society for Medical Oncology (ESMO)

Career opportunities and benefits for young oncologists in the European Society for Medical Oncology (ESMO)

The ESMO Preceptorship Programme: Throughout the year, ESMO offers preceptorship courses that are highly condensed and informative courses that focus on spe- ci fi c tumour sites. The ESMO Preceptorships are educa- tional courses that aim to present the current standard of care for a given malignancy in accordance with the ESMO clinical practice guidelines. The courses are con- ducted by leading experts in a particular fi eld of oncol- ogy. These meetings provide the oncologists with a complete multidisciplinary understanding of the man- agement of the disease from diagnosis to treatment. All major malignancies are covered in the programme and courses are organised in Europe and Asia. Preceptorships are held over 2 – 3 days and allow for close interaction with the faculty through didactic learn- ing, case studies and open discussions. These closed meetings host 60 – 100 delegates per course from all around the world. Participants are provided a great plat- form to interact with the faculty and colleagues and share experiences and ideas. Attendance to these events is by application and the process is competitive. The application requires the applicant ’ s curriculum vitae and list of publications, and a fi ve-slide clinical case presenta- tion on the topic of the preceptorship. Cases with the most merit will be chosen by the faculty and are pre- sented to the group by the participant. Dr Surendra Pal Chaudhary from India never thought he would ever meet the authors and innovators whose articles and research he had read and practised in his everyday clinic; yet through the ESMO Preceptorship, this became a reality. The preceptorship covers all of the aspects of disease, from epidemiology, diagnosis, advanced treatments, future goals and effective cancer therapies in the world. Dr Pal Chaudhary has attended many preceptorships and he testi fi es that through such ESMO activities, his knowledge, experience and skills have been taken to a new level and have improved his con fi dence as an oncologist. Through knowledge gath- ered by his experiences with ESMO, he has help to

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Identification of micro RNA expression profile related to recurrence in women with ESMO low risk endometrial cancer

Identification of micro RNA expression profile related to recurrence in women with ESMO low risk endometrial cancer

According to the ESMO-ESGO-ESTRO classifica- tion, low-risk group included FIGO Stage I endometri- oid carcinoma, histological grade 1–2, < 50% myometrial involvement, lympho vascular space involvement (LVSI) negative tumors. They all had disease free pelvic lymph nodes. Women underwent primary surgical treatment (including total hysterectomy, bilateral salpingo-oopho- rectomy, and systematic nodal staging with optional adjuvant brachytherapy according to French guidelines. Each one of them was matched according to histologic grade (grade 1 or grade 2) and age with two women without any recurrence (R−), who were used as control subjects. The exclusion criteria were as follows: Lynch syndrome (the search for a loss of expression of one of the Mismatch Repair proteins by immunohistochemistry and for tumor instability (microsatellite instability repli- cation error repeats phenotype) were performed when EC occurred before the age 50 years or when there was a suggestive family history) and refusal of consent.

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Neck paraganglioma and follicular lymphoma: a case report

Neck paraganglioma and follicular lymphoma: a case report

Our patient underwent surgery and histology was con- sistent with a carotid body PGL. Due to the presence of a germline SDHB gene mutation, a second malignancy was suspected; therefore, accurate histology examination was also pursued for the neck lymph nodes resected during surgery. In fact, a follicular lymphoma was documented as grade 1 according to the histological classification of the World Health Organization (WHO). The hematological assessment of our patient followed European Society for Medical Oncology (ESMO) guidelines; therefore, a contrast-enhanced CT scan of his neck, thorax, abdomen,

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Routine thyroglobulin, neck ultrasound and physical examination in the routine follow up of patients with differentiated thyroid cancer—Where is the evidence?

Routine thyroglobulin, neck ultrasound and physical examination in the routine follow up of patients with differentiated thyroid cancer—Where is the evidence?

The BTA recommends regular PE and Tg no more fre- quently than three-monthly. Patients who respond well to therapy are seen every 6 – 12 months. However, this is based on ‘ expert opinion ’ extrapolated from studies with different primary objectives [6]. The references listed in the guide- lines to support the recommendations on monitoring focus primarily on the practicality of Tg [6]. The ESMO recom- mends annual PE, serum Tg and US for long-term follow- up [10]. The strength of recommendation and the quality of supporting evidence are not clear.

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Safeguarding the future of independent, academic clinical cancer research in Europe for the benefit of patients

Safeguarding the future of independent, academic clinical cancer research in Europe for the benefit of patients

ABCSG, ACR-ITR, AGO, ANOCEF, ARCAGY GINECO, ASST, BIG, CML Advocates Network, EACR, EORTC, ESMO, ETOP, FFCD, FICOG, GCO, GEICAM, GEIS, GEMCAD, GERCOR, GOIRC, GORTEC, Hospital General Universitario Gregorio Marañón, IBCSG, IFCT, IOCN, IRCCS, JCOG, Jules Bordet Institute, LACOG, LMU, LYSA & LYSARC, MELAMONA Patient Network Europe, National & Kapodistrian University of Athens, Netherlands Cancer Institute, SAKK, SOCUG, TTD, UNICANCER, Vall d’Hebron Institut of Oncology.

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Cancer clinical research in Latin America: current situation and opportunities. Expert opinion from the first ESMO workshop on clinical trials, Lima, 2015

Cancer clinical research in Latin America: current situation and opportunities. Expert opinion from the first ESMO workshop on clinical trials, Lima, 2015

In order to improve participation and representation, collaborative teams and groups should be set up in regions historically under-represented in clinical trials. For example, the Central European Cooperative Oncology Group (CECOG) was set up in 1999 in Vienna, Austria. This group represents patients from its 23 member countries, with almost 200 oncology patients per year included in phase III and II clinical trials, and participation in phase I clinical trials. This effort has resulted in articles published in prestigious journals, high representation at the most important oncology con- ferences, and recognition within the oncology commu- nity as one of the foremost collaborative groups in cancer research worldwide (http://www.cecog.org). 10

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Dancing to the moon

Dancing to the moon

But then he was surrounded by all the trial officials, and people who were obviously his friends and fans. The moon was rising. A tiny slither of common sense crept back in. This wouldn’t work. I was an underage school girl, with a strange monthly cycle, who had school tomorrow. Better just to go home and dream about him.

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Overview of Venus orbiter, Akatsuki

Overview of Venus orbiter, Akatsuki

and structure, surface composition, and topography (Moroz, 1983). Although the surface of Venus was too hot for the entry probes to survive for more than two hours, their ob- servations gave us a rough idea about the Venusian envi- ronment. The Pioneer Venus orbiter and entry probes of U.S., which were launched in 1978, also provided plenty of new information on the atmosphere and the surface (Colin, 1980). The Vega balloons were dropped into the cloud layer of Venus by the Soviet Union and France in 1985 and ob- served meso-scale cloud processes and horizontal advection over 46 hours (Sagdeev et al., 1986). The U.S. probe Mag- ellan, which took off for Venus in 1989, radar-mapped the Venusian surface precisely (Saunders et al., 1992). In 1990, the Galileo spacecraft encountered Venus for a gravity as- sist to obtain kinetic energy to go to Jupiter, and at that time, it observed the Venus atmosphere (Johnson et al., 1991).

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Germination of Green Gram with Influence of Pyramid Energy and Lunar Days

Germination of Green Gram with Influence of Pyramid Energy and Lunar Days

82 Instead its lunar wake, formed from the solar wind, is blown downstream towards the earth’s magnetosphere in a relatively narrow pathway, but in a varied way because of the sun’s 11-year sun-spot cycle and the sun’s rotating magnetic field. The latter has two effects. Firstly, earth experiences reversed solar polarity when crossing sectors in the interplanetary magnetic field, typically twice in about 27 days [19]. Secondly, the solar wind travels in a spiral, so the lunar wake is not usually in direct alignment from the sun. This may be related to the allais effect, during solar eclipses, when the moon blocks the direct optical line of solar light to earth, but gravitational anomalies have been found at locations outside the eclipse path and time on earth [20]. Moon’s movement in an orbit around the earth affects the air currents on the earth, rise and fall of tides, and occurrence of thunderstorms [21]. For many years, farmers and craftsmen have carefully observed the moon phases while conducting certain forestry practices and planting, harvesting or collecting plants and rules are still being followed in accordance to the moon cycles [22]. There are evidences that near new moon, first quarter and after full moon (Super Moon) phases there is rise in the potassium contents of germinated seeds [23], correlations between magnetic variations and climate is more significant [24] and subjects who had slept with head in south direction for 12 weeks had lowest systolic blood pressure, diastolic blood pressure, heart rate and serum cortisol which was found to be statistically significant compared to other directions [25]. To study the fact that lunar days effect on germination of seeds, observed number of seeds germinated, radical length, fresh weight and oven dry weight and seeds were soaked at sunrise time in March/April (caitra) month.

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Moon phases and moon signs do not influence morbidity, mortality and long term survival, after living donor kidney transplantation

Moon phases and moon signs do not influence morbidity, mortality and long term survival, after living donor kidney transplantation

The majority of the transplant procedures had been planned irrespective of the moon cycle and moon signs. All surgeries were performed electively without exception. Therefore, all dates of LDKT were retro- spectively assigned to the corresponding dates of the four lunar phases (Fig. 2). Lunar phases were defined as follows: the period of the new moon was consid- ered to be ±1 day around the precise day of the new moon, so the entire new moon phase occupied 3 days. The full moon phase was defined similarly. The time interval between the new moon phase and the full moon phase was defined as the waxing moon phase and the time interval between the full moon phase and the new moon phase as the waning moon phase. Since a lunar month (synodic month) lasts about 29.53 days, the phases of waxing moon and of waning moon last approximately 12 days and therefore 4- times longer than the phases of full moon and new moon (3 days). Moon signs were defined as the signs of the Zodiac in which the moon was at the time of the operation. Lunar phases and moon signs for each date of transplantation were acquired from StarDate Online (online service of the University of Texas McDonald Observatory) [17]. According to medical astrology, the moon sign Libra is considered critical for renal and urogenital surgery (Fig. 1). Therefore, we additionally divided the patient cohort into two groups: those who underwent LDKT during the moon sign Libra, and those who did not.

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Chasing the moon

Chasing the moon

Scott is lying on the bed in the general hospital with an oxygen mask on next to the drip, Diana is hesitating whether to remove the oxygen mask or not. She takes a deep breath and leaves the room. Scott opens his eyes which are shimmering with reflected light from the moon. A full moon is coming. (Over the shoulder shot)

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Educational needs in gastrointestinal cancer: a consensus position paper from the ESMO Gastrointestinal Cancer Faculty

Educational needs in gastrointestinal cancer: a consensus position paper from the ESMO Gastrointestinal Cancer Faculty

Clinical case discussions between junior and senior GI oncologists for teaching purposes could be of help. Faculty members encourage ESMO to update regularly the clinical practice guidelines, to extend the courses such as the masterclasses and preceptorship programmes in Europe and beyond (Asia-Pacific region, Middle East, Africa and Latin America), and to further facilitate clin- ical fellowships and exchange programmes. Collabora- tion with patient organisations was also seen as useful and necessary.

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Detailed statistical assessment of the characteristics of the ESMO Magnitude of Clinical Benefit Scale (ESMO-MCBS) threshold rules

Detailed statistical assessment of the characteristics of the ESMO Magnitude of Clinical Benefit Scale (ESMO-MCBS) threshold rules

Background The European Society for Medical Oncology (ESMO) has developed the ESMO Magnitude of Clinical Benefit Scale (ESMO-MCBS), a tool to assess the magnitude of clinical benefit from new cancer therapies. Grading is guided by a dual rule comparing the relative benefit (RB) and the absolute benefit (AB) achieved by the therapy to prespecified threshold values. The ESMO- MCBS v1.0 dual rule evaluates the RB of an experimental treatment based on the lower limit of the 95%CI (LL95%CI) for the hazard ratio (HR) along with an AB threshold. This dual rule addresses two goals: inclusiveness: not unfairly penalising experimental treatments from trials designed with adequate power targeting clinically meaningful relative benefit; and discernment: penalising trials designed to detect a small inconsequential benefit. Methods Based on 50 000 simulations of plausible trial scenarios, the sensitivity and specificity of the LL95%CI rule and the ESMO-MCBS dual rule, the robustness of their characteristics for reasonable power and range of targeted and true HRs, are examined. The per cent acceptance of maximal preliminary grade is compared with other dual rules based on point estimate (PE) thresholds for RB. Results For particularly small or particularly large studies, the observed benefit needs to be relatively big for the ESMO-MCBS dual rule to be satisfied and the maximal grade awarded. Compared with approaches that evaluate RB using the PE thresholds, simulations demonstrate that the MCBS approach better exhibits the desired behaviour achieving the goals of both inclusiveness and discernment. Conclusions RB assessment using the LL95%CI for HR rather than a PE threshold has two advantages: it diminishes the probability of excluding big benefit positive studies from achieving due credit and, when combined with the AB assessment, it increases the probability of downgrading a trial with a statistically significant but clinically insignificant observed benefit.

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First optical observation of the Moon’s sodium exosphere from the lunar orbiter SELENE (Kaguya)

First optical observation of the Moon’s sodium exosphere from the lunar orbiter SELENE (Kaguya)

In-situ measurements carried out during the Apollo mis- sions revealed that the Moon has a surface boundary ex- osphere (Hoffman et al., 1973; Hodges, 1973, 1975). A major breakthrough in the study of this exosphere occurred with the discovery of D-line emissions of sodium (Na) and potassium (K) from the ground (Potter and Morgan, 1988; Tyler et al., 1988). Optical remote sensing techniques en- able us to investigate the source mechanism of Na atoms in terms of: (1) thermal desorption, (2) micrometeoroid im- pacts, (3) photodesorption by solar illumination, and (4) sputtering by solar-wind particles, including chemical reac- tions (see the review by Stern, 1999). These source mech- anisms, which give a wide variety of release velocities and ejection rates acting in different surface regions, produce the characteristic distribution and dynamics of the lunar ex- osphere. In particular, source mechanisms associated with the solar wind are suppressed for a few days before and af- ter the full moon because the lunar surface is shielded from the solar wind plasma by the Earth’s magnetosphere (Pot- ter and Morgan, 1991). Several observational studies have been carried out to test this effect (Potter and Morgan, 1994; Mendillo et al., 1999; Potter et al., 2000; Wilson et al., 2006), although continuous observation from the ground is difficult due to the strong reflection of sunlight during the full moon period.

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