scholarly journals Symmetric Constellations of Satellites Moving Around a Central Body of Large Mass

Author(s):  
Marco Fenucci ◽  
Giovanni Federico Gronchi
Keyword(s):  
1982 ◽  
Vol 99 ◽  
pp. 605-613
Author(s):  
P. S. Conti

Conti: One of the main conclusions of the Wolf-Rayet symposium in Buenos Aires was that Wolf-Rayet stars are evolutionary products of massive objects. Some questions:–Do hot helium-rich stars, that are not Wolf-Rayet stars, exist?–What about the stability of helium rich stars of large mass? We know a helium rich star of ∼40 MO. Has the stability something to do with the wind?–Ring nebulae and bubbles : this seems to be a much more common phenomenon than we thought of some years age.–What is the origin of the subtypes? This is important to find a possible matching of scenarios to subtypes.


Palaeobotany ◽  
2012 ◽  
Vol 3 ◽  
pp. 5-11
Author(s):  
A. V. Gomankov ◽  
V. F. Tarasevich

Dispersed bisaccate pollen grains of Scutasporites nanuki were studied by means of LM, SEM and TEM. Sacci ultrastructure of these pollen grains was rather peculiar. Sacci were like a thin fi lmy fringe attached to the central body near the equator. They were fi lled with sporopollenin elements of irregular shape and various dimensions with equally various cavities between them. Such an ultrastructure is called as spongy. The morphology and ultrastructure of S. nanuki is discussed in the context of the evolution of early conifers.


2016 ◽  
Author(s):  
Stephen T. Nelson ◽  
◽  
Kevin A. Rey ◽  
David G. Tingey ◽  
John H. McBride ◽  
...  

2019 ◽  
Vol 12 (12) ◽  
pp. e231320
Author(s):  
Mário José Pereira-Lourenço ◽  
Duarte Vieira-Brito ◽  
João Pedro Peralta ◽  
Noémia Castelo-Branco

This case report describes the case of a 37-year-old man that noticed an intrascrotal right mass with 1 month of evolution. During physical exam presented with a large mass at the inferior portion of the right testicle, clearly separated from the testicle, with a tender consistency and mobile. An ultrasound was performed that showed a solid and subcutaneous nodular lesion, extra testicular, heterogeneous, measuring 7.2 cm. Pelvic magnetic resonance imageMRI showed a lesion compatible with a lipoma. The patient was subjected to surgical excision of the lesion by scrotal access, having histology revealed a lipoblastoma (LB) of the scrotum. Histological diagnosis was obtained by microscopic characteristics (well-circumscribed fatty neoplasm) and immunohistochemistry (stains for CD34, S100 protein and PLAG1 were positive; stains for MDM2 and CDK4 were negative). LB is extremely rare after adolescence in any location, being this first described case of intrascrotal LB described in adulthood.


2019 ◽  
Vol 141 (6) ◽  
Author(s):  
Rui Xu ◽  
Yun Long ◽  
Yaoyu Hu ◽  
Junlian Yin ◽  
Dezhong Wang

Reactor coolant pump (RCP) is one of the most important equipment of the coolant loop in a pressurized water reactor system. Its safety relies on the characteristics of the rotordynamic system. For a canned motor RCP, the liquid coolant fills up the clearance between the metal shields of the rotor and stator inside the canned motor, forming a long clearance flow. The fluid-induced forces of the clearance flow in canned motor RCP and their effects on the rotordynamic characteristics of the pump are numerically and experimentally analyzed in this work. A transient computational fluid dynamics (CFD) method has been used to investigate the fluid-induced force of the clearance. A vertical experiment rig has also been established for the purpose of measuring the fluid-induced forces. Fluid-induced forces of clearance flow with various whirl frequencies and various boundary conditions are obtained through the CFD method and the experiment. Results show that clearance flow brings large mass coefficient into the rotordynamic system and the direct stiffness coefficient is negative under the normal operating condition. The rotordynamic stability of canned motor RCP does not deteriorate despite the existence of significant cross-coupled stiffness coefficient from the fluid-induced forces of the clearance flow.


2021 ◽  
Vol 57 (35) ◽  
pp. 4287-4290
Author(s):  
Ryohei Yamakado ◽  
Issei Kitamura ◽  
Mitsuo Hara ◽  
Shusaku Nagano ◽  
Takahiro Seki ◽  
...  

Large mass transport driven by the difference in the photoisomerization-induced surface tension was demonstrated in ion pairs, enabling fluorescence patterning using a trace amount of photoisomerized anions in complexation with a π-electronic system.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Lubna Bakr ◽  
Hussam AlKhalaf ◽  
Ahmad Takriti

Abstract Background Primary cardiac tumours are extremely rare. Most of them are benign. Sarcomas account for 95% of the malignant tumours. Prognosis of primary cardiac angiosarcoma remains poor. Complete surgical resection is oftentimes hampered when there is extensive tumour involvement into important cardiac apparatus. We report a case of cardiac angiosarcoma of the right atrium and ventricle, infiltrating the right atrioventricular junction and tricuspid valve. Case presentation Initially, a 22-year-old man presented with dyspnoea. One year later, he had recurrent pericardial effusion. Afterwards, echocardiography revealed a large mass in the right atrium, expanding from the roof of the right atrium to the tricuspid valve. The mass was causing compression on the tricuspid valve, and another mass was seen in the right ventricle. Complete resection of the tumour was impossible. The mass was resected with the biggest possible margins. The right atrium was reconstructed using heterologous pericardium. The patient’s postoperative course was uneventful. Postoperative echocardiography showed a small mass remaining in the right side of the heart. Histopathology and immunohistochemistry confirmed the diagnosis of angiosarcoma. The patient underwent adjuvant chemotherapy and radiotherapy later on. He survived for 1 year and 5 days after the surgery. After a diagnosis of lung and brain metastases, he ended up on mechanical ventilation for 48 h and died. Conclusions Surgical resection combined with postoperative chemotherapy and radiotherapy is feasible even in patients with an advanced stage of cardiac angiosarcoma when it is impossible to perform complete surgical resection.


Author(s):  
Avnish Kumar Seth ◽  
Mahesh Kumar Gupta ◽  
Rinkesh Kumar Bansal ◽  
Radha Krishan Verma ◽  
Gursimran Kaur

Abstract Introduction Fecaloma is a large mass of organized hardened feces causing impaction, usually in rectum and sigmoid colon. Medical management usually entails digital evacuation, use of clearance enema, and oral laxatives. We report two patients managed successfully with colonoscopic instillation of Coca-Cola and review the literature. Case Report Patient 1: A 37-year-old male presented with firm, nontender, pitting mass over lower abdomen for 2 months and inability to pass stool for 1 month. Per-rectal examination and imaging confirmed presence of solid stool with gross distension of rectum and sigmoid colon. Attempts at clearance of stool with conventional methods were unsuccessful. At colonoscopy, 4 L of Coca-Cola was instilled into descending and sigmoid colon, leading to evacuation of 10 L of fragmented and liquid stool.Patient 2: A 72-year-old diabetic lady presented with constipation and tender, firm pelvic mass extending till mid-abdomen for 6 months. Per-rectal examination revealed presence of hard stool. Imaging confirmed large amount of fecal matter in dilated rectum, sigmoid, and descending colon. Attempts at evacuating stool with digital evacuation, sodium phosphate enema, and oral polyethylene glycol were unsuccessful. At colonoscopy, two sittings of instillation of 990 mL of Coca-Cola Light each were done into sigmoid colon over 2 days, resulting in clearance. Conclusion Colonoscopic instillation of Coca-Cola may be effective in evacuation of large fecaloma from rectum, sigmoid, and descending colon when refractory to use of conventional methods like digital disimpaction, rectal enema, and oral laxatives.


Among the celestial bodies the sun is certainly the first which should attract our notice. It is a fountain of light that illuminates the world! it is the cause of that heat which main­tains the productive power of nature, and makes the earth a fit habitation for man! it is the central body of the planetary system; and what renders a knowledge of its nature still more interesting to us is, that the numberless stars which compose the universe, appear, by the strictest analogy, to be similar bodies. Their innate light is so intense, that it reaches the eye of the observer from the remotest regions of space, and forcibly claims his notice. Now, if we are convinced that an inquiry into the nature and properties of the sun is highly worthy of our notice, we may also with great satisfaction reflect on the considerable progress that has already been made in our knowledge of this eminent body. It would require a long detail to enumerate all the various discoveries which have been made on this subject; I shall, therefore, content myself with giving only the most capital of them.


Author(s):  
Bharath V. ◽  
Milind Padmakar Hote

AbstractA 57-year-old female presented to emergency with features of right heart failure. On evaluation, she was found to have a large mass occupying right atrium (RA) completely and protruding into right ventricle through tricuspid valve. Intraoperatively, mass was seen arising from RA free wall with stony hard consistency. Histopathology revealed it to be myxoma. We present this case for the rare presentation of myxoma masquerading as malignancy.


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