Long time gap between events sinks discrimination claim

2021 ◽  
Vol 2021 (377) ◽  
pp. 10-11
Keyword(s):  
2011 ◽  
Vol 101 (3) ◽  
pp. 125-130 ◽  
Author(s):  
John M Griffin ◽  
Dragon Yongjun Tang

We compare key CDO assumptions from two departments within the same rating agency but with different financial incentives. Assumptions made by the ratings division are more favorable than those by the surveillance department. The differences are not explained by collateral switching during the ramp-up period, a long time gap between reports, nor the collapse of the CDO market in 2007 Additionally, CDOs rated with more favorable assumptions by the ratings group were more likely to be subsequently downgraded. As the useful signals from the surveillance group were seemingly ignored, these findings suggest rating agencies bias towards high ratings.


Author(s):  
Shunsuke Takada ◽  
Mamoru Narukawa

Abstract Objective In England, the time gap between marketing authorization (MA) and guidance publication by National Institute for Health and Care Excellence (NICE) can limit patients’ access to new medicines. In this study, our aim was to identify medicine characteristics associated with the long time gap between MA and guidance publication and explore the influencing factors. Methods We identified 116 single technology appraisals from 2016 to 2020 using publicly available data, and extracted information on the year of appraisal completion, application type, experiences of similar appraisals, orphan medicinal products (OMPs), cancer medicines, and accelerated assessment. Multiple regression analyses were performed to analyze the associations between the medicine characteristics and key time periods related to health technology assessment and MA processes. Results OMPs were associated with a long period between MA and guidance publication. Specifically, OMPs and cancer medicines were associated with slow guidance publication after the final scope (FS) development. However, there was no association between OMPs and the period between validation of MA application and FS development. Non-double-blinded randomized clinical trials and the use of comparators not specified in the FS were associated with slow guidance publication after the FS development. Conclusions Our results demonstrate that OMPs are associated with a longer period between MA and guidance publication by the NICE than non-OMPs; this may be attributed to the slow guidance publication after the FS development. These findings indicate the necessity to shorten the appraisal process for OMPs.


2021 ◽  
Author(s):  
Qian Chen

The principle of the constancy of the velocity of light, which stated that the light velocity is invariant to the motion of the emitter, was well established and experimentally proven. Interestingly, the further assumption that the light velocity is independent of the motion of the observer was never directly proven by any experiment for a century. This paper proposed the design of two experiments to directly test this assumption. One is to directly measure the light speed as to moving sensors. The experiment setup is designed in such a way that the concerns of time synchronization and dilation can be avoided. Another experiment is to test the isotropy of the light speed to a moving particle in the electromagnetic accelerator by measuring the momentum to acceleration ratio. Since the light speed invariance to observers is a key assumption, the experiment result, if positive, will cover a long-time gap. Otherwise, it may imply a need for further investigation. Either way, the experiments will have significant meanings in physical theory.


Author(s):  
M. Iwatsuki ◽  
Y. Kokubo ◽  
Y. Harada ◽  
J. Lehman

In recent years, the electron microscope has been significantly improved in resolution and we can obtain routinely atomic-level high resolution images without any special skill. With this improvement, the structure analysis of organic materials has become one of the interesting targets in the biological and polymer crystal fields.Up to now, X-ray structure analysis has been mainly used for such materials. With this method, however, great effort and a long time are required for specimen preparation because of the need for larger crystals. This method can analyze average crystal structure but is insufficient for interpreting it on the atomic or molecular level. The electron microscopic method for organic materials has not only the advantage of specimen preparation but also the capability of providing various information from extremely small specimen regions, using strong interactions between electrons and the substance. On the other hand, however, this strong interaction has a big disadvantage in high radiation damage.


Author(s):  
YIQUN MA

For a long time, the development of dynamical theory for HEER has been stagnated for several reasons. Although the Bloch wave method is powerful for the understanding of physical insights of electron diffraction, particularly electron transmission diffraction, it is not readily available for the simulation of various surface imperfection in electron reflection diffraction since it is basically a method for bulk materials and perfect surface. When the multislice method due to Cowley & Moodie is used for electron reflection, the “edge effects” stand firmly in the way of reaching a stationary solution for HEER. The multislice method due to Maksym & Beeby is valid only for an 2-D periodic surface.Now, a method for solving stationary solution of HEER for an arbitrary surface is available, which is called the Edge Patching method in Multislice-Only mode (the EPMO method). The analytical basis for this method can be attributed to two important characters of HEER: 1) 2-D dependence of the wave fields and 2) the Picard iteractionlike character of multislice calculation due to Cowley and Moodie in the Bragg case.


Author(s):  
Yimei Zhu ◽  
J. Tafto

The electron holes confined to the CuO2-plane are the charge carriers in high-temperature superconductors, and thus, the distribution of charge plays a key role in determining their superconducting properties. While it has been known for a long time that in principle, electron diffraction at low angles is very sensitive to charge transfer, we, for the first time, show that under a proper TEM imaging condition, it is possible to directly image charge in crystals with a large unit cell. We apply this new way of studying charge distribution to the technologically important Bi2Sr2Ca1Cu2O8+δ superconductors.Charged particles interact with the electrostatic potential, and thus, for small scattering angles, the incident particle sees a nuclei that is screened by the electron cloud. Hence, the scattering amplitude mainly is determined by the net charge of the ion. Comparing with the high Z neutral Bi atom, we note that the scattering amplitude of the hole or an electron is larger at small scattering angles. This is in stark contrast to the displacements which contribute negligibly to the electron diffraction pattern at small angles because of the short g-vectors.


Author(s):  
M. G. Burke ◽  
M. N. Gungor ◽  
M. A. Burke

Intermetallic matrix composites are candidates for ultrahigh temperature service when light weight and high temperature strength and stiffness are required. Recent efforts to produce intermetallic matrix composites have focused on the titanium aluminide (TiAl) system with various ceramic reinforcements. In order to optimize the composition and processing of these composites it is necessary to evaluate the range of structures that can be produced in these materials and to identify the characteristics of the optimum structures. Normally, TiAl materials are difficult to process and, thus, examination of a suitable range of structures would not be feasible. However, plasma processing offers a novel method for producing composites from difficult to process component materials. By melting one or more of the component materials in a plasma and controlling deposition onto a cooled substrate, a range of structures can be produced and the method is highly suited to examining experimental composite systems. Moreover, because plasma processing involves rapid melting and very rapid cooling can be induced in the deposited composite, it is expected that processing method can avoid some of the problems, such as interfacial degradation, that are associated with the relatively long time, high temperature exposures that are induced by conventional processing methods.


Author(s):  
Shailesh R. Sheth ◽  
Jayesh R. Bellare

Specimen support and astigmatism correction in Electron Microscopy are at least two areas in which lacey polymer films find extensive applications. Although their preparation has been studied for a very long time, present techniques still suffer from incomplete release of the film from its substrate and presence of a large number of pseudo holes in the film. Our method ensures complete removal of the entire lacey film from the substrate and fewer pseudo holes by pre-treating the substrate with Gum Arabic, which acts as a film release agent.The method is based on the classical condensation technique for preparing lacey films which is essentially deposition of minute water or ice droplets on the substrate and laying the polymer film over it, so that micro holes are formed corresponding to the droplets. A microscope glass slide (the substrate) is immersed in 2.0% (w/v) aq. CTAB (cetyl trimethyl ammonium bromide)-0.22% (w/v) aq.


Author(s):  
K.-H. Herrmann ◽  
W. D. Rau ◽  
R. Sikeler

Quantitative recording of electron patterns and their rapid conversion into digital information is an outstanding goal which the photoplate fails to solve satisfactorily. For a long time, LLL-TV cameras have been used for EM adjustment but due to their inferior pixel number they were never a real alternative to the photoplate. This situation has changed with the availability of scientific grade slow-scan charged coupled devices (CCD) with pixel numbers exceeding 106, photometric accuracy and, by Peltier cooling, both excellent storage and noise figures previously inaccessible in image detection technology. Again the electron image is converted into a photon image fed to the CCD by some light optical transfer link. Subsequently, some technical solutions are discussed using the detection quantum efficiency (DQE), resolution, pixel number and exposure range as figures of merit.A key quantity is the number of electron-hole pairs released in the CCD sensor by a single primary electron (PE) which can be estimated from the energy deposit ΔE in the scintillator,


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