scholarly journals Cherenkov-channeling radiation by relativistic muons in crystals

2020 ◽  
Vol 80 (10) ◽  
Author(s):  
K. B. Korotchenko ◽  
E. I. Rozhkova ◽  
S. B. Dabagov

AbstractIn this work we analyse Cherenkov radiation by relativistic muons, positive and negative, channeled in optically transparent diamond and silicon crystals in comparison with ordinary Cherenkov radiation. We have shown that the maxima in the spectral angular distributions for both types of radiation are revealed at the derivative extrema for the media refractive index, while, due to the difference in scattering of positively and negatively charged particles at crystal channeling, the number of Cherenkov photons emitted by channeled positive muons might be over the one for negative muons. We have demonstrated that Cherenkov radiation by quasi free projectiles is described as one limiting approximation of a general expression for Cherenkov radiation by channeled projectiles, which takes into account non-zero derivative of the refractive index. The last may result in essential increase of radiation intensity.

2020 ◽  
Vol 8 (10) ◽  
pp. 272-278
Author(s):  
Koderi a ◽  
◽  
Agus Jatmiko ◽  
Guntur Cahaya Kesuma ◽  
Dwi Prasetyo ◽  
...  

The purpose of this study was to develop mobile learning media for the Arabic Mufradatcourse during the COVID-19 pandemic and see the feasibility and effectiveness of the developed media for mastering Mufrodat. The Alessi and Trollip development model was used that consisted of planning, designing, and developing stages. The validation score obtained from the product design experts was 4.7 or 94%, from the material experts was 4.6 or 93%, and from the media experts were 4.6 or 96.25%. It means that the developed product was highly feasible to use. The result of the one-to-one learner trial was 2.9 or 94%, the small-group trial was 7.8 or 89%, and the large-group trial was 18.5 or 93%. To test the products effectiveness, a t-test was performed using tobserved> tcritical = 62.5>2.093, where the difference in learning outcomes was 38.75. it can be concluded that the mobile learning media for the Arabic Mufradatcourse during the COVID-19 pandemic was highly feasible and effective to be used in the Arabic Mufrodat course in Indonesia.


1995 ◽  
Vol 52 ◽  
pp. 93-104
Author(s):  
Wasif Shadid

Research in both Europe and America indicates that the way in which mass communication deals with ethnic minorities contributes directly and indirectly to the diffusion and the maintenance of prejudice against these groups. These are generally projected as problem categories in cultural and in socioeconomic sense. In this article we pay attention to the causes and functions of prejudice and especially to the role of mass communication media in this regard. Furthermore, attention is paid to the possibilities of and the extent to which the media can succeed in fighting against such negative attitudes towards the groups concerned. In this regard, a distinction is made between preventive and interven-tive strategies. Based on certain theories of social psychology on attitude forming and on the use and absorption of information it is concluded that though manipulation of attitude is not easily achieved, it is nevertheless possible. Various experi-ments in similar fields show that, under certain conditions, the supply of informa-tion through an adequate intervention strategy of the media can to some extent generate attitude change in the desired direction. However, such a positive result can only be achieved (1) if the basic thoughts underlying the prejudice concerned can be accurately identified; (2) if the difference between the information provided on the one hand and the existing information on the other is neither too weak nor too strong; (3) if the relevant information is provided by prominent persons and media in society; and (4) if the intended message emphasizes the positive rather than the negative similarities between minorities and the other groups. Because of the complexity of such an intervention process it is doubtfull whether the media can actually play an effective role in this context. Consequently, being attentive to the way in which the media provide information about the groups concerned is a more appropriate strategy in preventing the diffusion of prejudice. In this article, some relevant suggestions in this regard have been discussed.


1975 ◽  
Vol 34 (02) ◽  
pp. 426-444 ◽  
Author(s):  
J Kahan ◽  
I Nohén

SummaryIn 4 collaborative trials, involving a varying number of hospital laboratories in the Stockholm area, the coagulation activity of different test materials was estimated with the one-stage prothrombin tests routinely used in the laboratories, viz. Normotest, Simplastin-A and Thrombotest. The test materials included different batches of a lyophilized reference plasma, deep-frozen specimens of diluted and undiluted normal plasmas, and fresh and deep-frozen specimens from patients on long-term oral anticoagulant therapy.Although a close relationship was found between different methods, Simplastin-A gave consistently lower values than Normotest, the difference being proportional to the estimated activity. The discrepancy was of about the same magnitude on all the test materials, and was probably due to a divergence between the manufacturers’ procedures used to set “normal percentage activity”, as well as to a varying ratio of measured activity to plasma concentration. The extent of discrepancy may vary with the batch-to-batch variation of thromboplastin reagents.The close agreement between results obtained on different test materials suggests that the investigated reference plasma could be used to calibrate the examined thromboplastin reagents, and to compare the degree of hypocoagulability estimated by the examined PIVKA-insensitive thromboplastin reagents.The assigned coagulation activity of different batches of the reference plasma agreed closely with experimentally obtained values. The stability of supplied batches was satisfactory as judged from the reproducibility of repeated measurements. The variability of test procedures was approximately the same on different test materials.


1970 ◽  
pp. 38-45
Author(s):  
May Abu Jaber

Violence against women (VAW) continues to exist as a pervasive, structural,systematic, and institutionalized violation of women’s basic human rights (UNDivision of Advancement for Women, 2006). It cuts across the boundaries of age, race, class, education, and religion which affect women of all ages and all backgrounds in every corner of the world. Such violence is used to control and subjugate women by instilling a sense of insecurity that keeps them “bound to the home, economically exploited and socially suppressed” (Mathu, 2008, p. 65). It is estimated that one out of every five women worldwide will be abused during her lifetime with rates reaching up to 70 percent in some countries (WHO, 2005). Whether this abuse is perpetrated by the state and its agents, by family members, or even by strangers, VAW is closely related to the regulation of sexuality in a gender specific (patriarchal) manner. This regulation is, on the one hand, maintained through the implementation of strict cultural, communal, and religious norms, and on the other hand, through particular legal measures that sustain these norms. Therefore, religious institutions, the media, the family/tribe, cultural networks, and the legal system continually disciplinewomen’s sexuality and punish those women (and in some instances men) who have transgressed or allegedly contravened the social boundaries of ‘appropriateness’ as delineated by each society. Such women/men may include lesbians/gays, women who appear ‘too masculine’ or men who appear ‘too feminine,’ women who try to exercise their rights freely or men who do not assert their rights as ‘real men’ should, women/men who have been sexually assaulted or raped, and women/men who challenge male/older male authority.


1975 ◽  
Vol 14 (3) ◽  
pp. 370-375
Author(s):  
M. A. Akhtar

I am grateful to Abe, Fry, Min, Vongvipanond, and Yu (hereafter re¬ferred to as AFMVY) [1] for obliging me to reconsider my article [2] on the demand for money in Pakistan. Upon careful examination, I find that the AFMVY results are, in parts, misleading and that, on the whole, they add very little to those provided in my study. Nevertheless, the present exercise as well as the one by AFMVY is useful in that it furnishes us with an opportunity to view some of the fundamental problems involved in an empi¬rical analysis of the demand for money function in Pakistan. Based on their elaborate critique, AFMVY reformulate the two hypo¬theses—the substitution hypothesis and the complementarity hypothesis— underlying my study and provide us with some alternative estimates of the demand for money in Pakistan. Briefly their results, like those in my study, indicate that income and interest rates are important in deter¬mining the demand for money. However, unlike my results, they also suggest that the price variable is a highly significant determinant of the money demand function. Furthermore, while I found only a weak support for the complementarity between money demand and physical capital, the results obtained by AFMVY appear to yield a strong support for that rela¬tionship.1 The difference in results is only a natural consequence of alter¬native specifications of the theory and, therefore, I propose to devote most of this reply to the criticisms raised by AFMVY and the resulting reformulation of the two mypotheses.


2019 ◽  
Vol 67 (6) ◽  
pp. 483-492
Author(s):  
Seonghyeon Baek ◽  
Iljae Lee

The effects of leakage and blockage on the acoustic performance of particle filters have been examined by using one-dimensional acoustic analysis and experimental methods. First, the transfer matrix of a filter system connected to inlet and outlet pipes with conical sections is measured using a two-load method. Then, the transfer matrix of a particle filter only is extracted from the experiments by applying inverse matrices of the conical sections. In the analytical approaches, the one-dimensional acoustic model for the leakage between the filter and the housing is developed. The predicted transmission loss shows a good agreement with the experimental results. Compared to the baseline, the leakage between the filter and housing increases transmission loss at a certain frequency and its harmonics. In addition, the transmission loss for the system with a partially blocked filter is measured. The blockage of the filter also increases the transmission loss at higher frequencies. For the simplicity of experiments to identify the leakage and blockage, the reflection coefficients at the inlet of the filter system have been measured using two different downstream conditions: open pipe and highly absorptive terminations. The experiments show that with highly absorptive terminations, it is easier to see the difference between the baseline and the defects.


Author(s):  
Sagar Suman Panda ◽  
Ravi Kumar B.V.V.

Three new analytical methods were optimized and validated for the estimation of tigecycline (TGN) in its injection formulation. A difference UV spectroscopic, an area under the curve (AUC), and an ultrafast liquid chromatographic (UFLC) method were optimized for this purpose. The difference spectrophotometric method relied on the measurement of amplitude when equal concentration solutions of TGN in HCl are scanned against TGN in NaOH as reference. The measurements were done at 340 nm (maxima) and 410nm (minima). Further, the AUC under both the maxima and minima were measured at 335-345nm and 405-415nm, respectively. The liquid chromatographic method utilized a reversed-phase column (150mm×4.6mm, 5µm) with a mobile phase of methanol: 0.01M KH2PO4 buffer pH 3.5 (using orthophosphoric acid) in the ratio 80:20 %, v/v. The flow rate was 1.0ml/min, and diode array detection was done at 349nm. TGN eluted at 1.656min. All the methods were validated for linearity, precision, accuracy, stability, and robustness. The developed methods produced validation results within the satisfactory limits of ICH guidance. Further, these methods were applied to estimate the amount of TGN present in commercial lyophilized injection formulations, and the results were compared using the One-Way ANOVA test. Overall, the methods are rapid, simple, and reliable for routine quality control of TGN in the bulk and pharmaceutical dosage form. 


Author(s):  
M. Rahul ◽  
R. Ganesan

Leaders in the global arena are the one who face the challenges never seen before, while coordinating work and managing relationship between team members coming from varied ethnic groups. Globalization has undoubtedly opened up endless growth opportunities for both, businesses and individuals, by collaborating with each other, but with certain inherent challenges. These challenges are the difference in the cultural background of the team members, which gets predominantly reflected in their behavior at workplace too. The cultural differences exist primarily due to differences in shared values, which form the basis for difference in perception and practices of decision making by an individual (Hofstede, 1980). Juana Bordas has rightly described that any business that fails to adapt their leadership style aligning with multi-cultural approach will find it difficult to thrive in a more colorful world. Leadership style has witnessed various facets of changing work environment that has demanded from leaders to modify their approach to adapt along and be effective and survive in the ever-changing environment of business (Bordas,2007).A cross-culture leader plays a significant role in knitting the diverse workforce into an efficient team; which requires a leader to very well understand the various dimensions of culture. This understanding of the leader enables him to learn about blending of leadership styles to address the challenges of such work environment. This paper is an extended work on 'Leadership in Cross-Cultural Environment – A Comparison of Asian and Non-Asian Managers' (Rahul and Ganesan, 2015). The extended research study has identified that enhanced work experience of cross-culture leaders enables them in effective team management, than the rise in designation, as it results in creation of hierarchical distance between the leaders and subordinates.


1995 ◽  
Vol 60 (11) ◽  
pp. 1875-1887 ◽  
Author(s):  
Jaroslav Holoubek ◽  
Miroslav Raab

Theoretical background for an optical method is presented which makes it possible to distinguish unambiguously between voids and particles as light scattering sites in polymeric materials. Typical dependences of turbidity as a function of diameter of scattering elements, their volume fractions and also turbidity curves as a function of the wavelength of the incident light were calculated, based both on the Lorenz-Mie theory and the fluctuation theory. Such dependences calculated for polypropylene-containing voids on the one hand and particles, differing only slightly from the surrounding matrix in their refractive index, on the other hand, are markedly different. The most significant results are: (i) Turbidity is at least by two orders of magnitude larger for voids in comparison to embedded particles of ethylene-propylene (EPDM) rubber of the same size, concentration and at the same wavelength. (ii) The wavelength dependence of turbidity for EPDM particles and the inherent refractive index fluctuations in the polypropylene matrix is much steeper as compared to voids for all considered diameters (0.1-10 μm). Thus, the nature of stress whitening in complex polymeric materials can be determined from turbidity measurements.


Dreyfus argues that there is a basic methodological difference between the natural sciences and the social sciences, a difference that derives from the different goals and practices of each. He goes on to argue that being a realist about natural entities is compatible with pluralism or, as he calls it, “plural realism.” If intelligibility is always grounded in our practices, Dreyfus points out, then there is no point of view from which one can ask about or provide an answer to the one true nature of ultimate reality. But that is consistent with believing that the natural sciences can still reveal the way the world is independent of our theories and practices.


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