Influence of a hyperbolic flyby of a small mass on the orbital evolution of a massive binary

1987 ◽  
Vol 41 (1-4) ◽  
pp. 313-321 ◽  
Author(s):  
L. K. Babadzanjanz ◽  
V. A. Brumberg
Keyword(s):  
2014 ◽  
Vol 23 (07) ◽  
pp. 1450064 ◽  
Author(s):  
Wen-Biao Han

Based on the numerical frame which combines the effective one-body (EOB) dynamics with the frequency-domain Teukolsky equation, we calculate the waveforms from the extreme-mass-ratio inspirals (EMRIs) with equatorially eccentric orbits. The EOB dynamics offers source term for solving the Teukolsky equation and also orbital evolution. At the same time, numerical calculation of the Teukolsky equation in frequency domain can give accurate waveform templates. Use of the EOB dynamics but not the shrinking geodesic orbit can include the conservative correction of mass-ratio so that make sure accurate frequency components, and also can give more appropriate orbital evolution. By simple analysis of the influence of the mass-ratio on orbital frequencies, and also signal losses caused by small mass-ratio ν, we suggest for the mass-ratio ≳ 10-5, it should be better to use the EOB Hamiltonian and dynamics but not geodesic inspirals to calculate the source term in the Teukolsky equation for generating waveforms.


Author(s):  
R. C. Moretz ◽  
G. G. Hausner ◽  
D. F. Parsons

Use of the electron microscope to examine wet objects is possible due to the small mass thickness of the equilibrium pressure of water vapor at room temperature. Previous attempts to examine hydrated biological objects and water itself used a chamber consisting of two small apertures sealed by two thin films. Extensive work in our laboratory showed that such films have an 80% failure rate when wet. Using the principle of differential pumping of the microscope column, we can use open apertures in place of thin film windows.Fig. 1 shows the modified Siemens la specimen chamber with the connections to the water supply and the auxiliary pumping station. A mechanical pump is connected to the vapor supply via a 100μ aperture to maintain steady-state conditions.


1974 ◽  
Vol 75 (2) ◽  
pp. 286-296 ◽  
Author(s):  
J. H. Lockefeer ◽  
W. H. L. Hackeng ◽  
J. C. Birkenhäger

ABSTRACT In 22 of 28 cases of primary hyperparathyroidism (PHP) the rise in the serum immunoreactive parathyroid hormone (IRPTH or PTH) level observed in response to lowering of the serum calcium by EDTA, exceeded that obtained in 8 control subjects. In 5 of these 22 patients who were studied again after parathyroidectomy the supranormal response was abolished. Fifteen of these 22 hyper-responsive PHP patients had basal IRPTH levels not exceeding the highest level in the controls and that of other groups of patients investigated (idiopathic hypercalciuria, non-parathyroid hypercalcaemia, operated PHP). Fourteen of the 22 hyper-reactive patients with PHP did not show hypocalcaemia during the infusion of EDTA. The extent of the release of PTH elicited by EDTA in cases of PHP does not as yet allow a prediction of the amount of pathological parathyroid tissue present, although all the PHP patients showing a normal release of PTH had a relatively small mass of parathyroid tissue (up to about 1 g) subsequently removed. In 9 cases of nephrolithiasis (8 of whom had idiopathic hypercalciuria) and in 7 cases of non-parathyroid hypercalcaemia, a normal PTH release was found.


1990 ◽  
Author(s):  
LARRY FRIESEN ◽  
ALBERT JACKSON, IV ◽  
HERBERT ZOOK ◽  
DONALD KESSLER
Keyword(s):  

2010 ◽  
Vol 52 (11-12) ◽  
pp. 765-770 ◽  
Author(s):  
Stefan Dietrich ◽  
Jan Kuppinger ◽  
Peter Elsner ◽  
Kay Weidenmann

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.


2021 ◽  
Vol 2021 (2) ◽  
Author(s):  
Amin Aboubrahim ◽  
Michael Klasen ◽  
Pran Nath

Abstract We present a particle physics model to explain the observed enhancement in the Xenon-1T data at an electron recoil energy of 2.5 keV. The model is based on a U(1) extension of the Standard Model where the dark sector consists of two essentially mass degenerate Dirac fermions in the sub-GeV region with a small mass splitting interacting with a dark photon. The dark photon is unstable and decays before the big bang nucleosynthesis, which leads to the dark matter constituted of two essentially mass degenerate Dirac fermions. The Xenon-1T excess is computed via the inelastic exothermic scattering of the heavier dark fermion from a bound electron in xenon to the lighter dark fermion producing the observed excess events in the recoil electron energy. The model can be tested with further data from Xenon-1T and in future experiments such as SuperCDMS.


2021 ◽  
Vol 2021 (4) ◽  
Author(s):  
Soo-Min Choi ◽  
Hyun Min Lee ◽  
Bin Zhu

Abstract We consider a novel mechanism to realize exothermic dark matter with dark mesons in the limit of approximate flavor symmetry in a dark QCD. We introduce a local dark U(1)′ symmetry to communicate between dark mesons and the Standard Model via Z′ portal by partially gauging the dark flavor symmetry with flavor-dependent charges for cancelling chiral anomalies in the dark sector. After the dark local U(1)′ is broken spontaneously by the VEV of a dark Higgs, there appear small mass splittings between dark quarks, consequently, leading to small split masses for dark mesons, required to explain the electron recoil excess in XENON1T by the inelastic scattering between dark mesons and electron. We propose a concrete benchmark model for split dark mesons based on SU(3)L× SU(3)R/SU(3)V flavor symmetry and SU(Nc) color group and show that there exists a parameter space making a better fit to the XENON1T data with two correlated peaks from exothermic processes and satisfying the correct relic density, current experimental and theoretical constraints.


Proteomes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 18
Author(s):  
Alaa Hseiky ◽  
Marion Crespo ◽  
Sylvie Kieffer-Jaquinod ◽  
François Fenaille ◽  
Delphine Pflieger

(1) Background: The proteomic analysis of histones constitutes a delicate task due to the combination of two factors: slight variations in the amino acid sequences of variants and the multiplicity of post-translational modifications (PTMs), particularly those occurring on lysine residues. (2) Methods: To dissect the relationship between both aspects, we carefully evaluated PTM identification on lysine 27 from histone H3 (H3K27) and the artefactual chemical modifications that may lead to erroneous PTM determination. H3K27 is a particularly interesting example because it can bear a range of PTMs and it sits nearby residues 29 and 31 that vary between H3 sequence variants. We discuss how the retention times, neutral losses and immonium/diagnostic ions observed in the MS/MS spectra of peptides bearing modified lysines detectable in the low-mass region might help validate the identification of modified sequences. (3) Results: Diagnostic ions carry key information, thereby avoiding potential mis-identifications due to either isobaric PTM combinations or isobaric amino acid-PTM combinations. This also includes cases where chemical formylation or acetylation of peptide N-termini artefactually occurs during sample processing or simply in the timeframe of LC-MS/MS analysis. Finally, in the very subtle case of positional isomers possibly corresponding to a given mass of lysine modification, the immonium and diagnostic ions may allow the identification of the in vivo structure.


Sign in / Sign up

Export Citation Format

Share Document