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On Ups and Downs of Chinese Cultural Confidence  [cached]
Guiying Zhou
Asian Culture and History , 2012, DOI: 10.5539/ach.v4n2p140
Abstract: Chinese nationality has experienced ups and downs in its cultural confidence with the nation’s rise and fall. China has become the world’s second largest economy and its cultural confidence should be enhanced so that China’s soft power will be strengthened too. Chinese cultural confidence can be restored by taking the following three measures: to improve cultural awareness, to understand and rethink traditional Chinese culture deeply and to deal with the relationship between Chinese culture and western culture properly.
Challenges to Sociology in Iran (Ups and Downs and Perspective of Exit)  [cached]
Ali Tayefi
Asian Social Science , 2010, DOI: 10.5539/ass.v7n1p170
Abstract: The sociology in Iran, as a scientific discipline, has been established in the academic and research centers around 70 years ago. This scientific discipline is continuing to produce knowledge and educating students despite many ups and downs during these seven decades. An overview to the history of developing of the sociology in Iran shows that it still facing with many challenges and serious crises although many books, articles have written or translated to Persian and many research projects have been conducted. In this article, through a historic perspective to the processes of development of the sociological schools affected by different ideological viewpoints from Marxism and Islamism; first, I try to define the main approaches of analyzing social problems according to these ideological viewpoints. The other aim of the article is studying the historical periods of formation and the development of various sociological approaches in this scientific discipline. In this process, I will analyze the development of sociology in two formal and informal sectors. Finally, I conclude that the sociology in Iran has many structural crises that will face many obstacles and difficulties for problematizing and resolving the socio/cultural issues without identifying the causes and consequences of these crises.
The ups and downs of biological timers
Noa Rappaport, Shay Winter, Naama Barkai
Theoretical Biology and Medical Modelling , 2005, DOI: 10.1186/1742-4682-2-22
Abstract: We compared the robustness of different mechanisms for encoding delay times to fluctuations in protein expression levels. Gradual accumulation and gradual decay of a regulatory protein have an equivalent capacity for defining delay times. Yet, we find that the former is highly sensitive to fluctuations in gene dosage, while the latter can buffer such perturbations. In particular, a positive feedback where the degrading protein auto-enhances its own degradation may render delay times practically insensitive to gene dosage.While our understanding of biological timing mechanisms is still rudimentary, it is clear that there is an ample use of degradation as well as self-enhanced degradation in processes such as cell cycle and circadian clocks. We propose that degradation processes, and specifically self-enhanced degradation, will be preferred in processes where maintaining the robustness of timing is important.Protein levels within cells are subject to genetic and environmental variations, but mechanisms have evolved that buffer cellular processes against those fluctuations [1]. Quantitative analysis has indicated that the need to ensure robustness can largely restrict the design of the underlying network [2-4]. Maintaining a reliable sequence of events appears straightforward in cases where the completion of one event directly triggers the next [5]. Often, however, temporal cascades are propagated by a self-sustained biochemical network, which functions even in the absence of feedback signals [6]. For example, the cell cycle is governed by an autonomous oscillator, although this oscillator is executively sensitive to checkpoint signals that may halt its progression [7]. Similarly, while the circadian timing is synchronized by light or temperature, it oscillates as well under constant conditions [8]. The prevalence of self-sustained networks that coordinate temporal cascades suggests that at least in certain cases not only is the temporal order important, but also the r
The Ups and Downs of Cyclic Universes  [PDF]
T. Clifton,John D. Barrow
Physics , 2007, DOI: 10.1103/PhysRevD.75.043515
Abstract: We investigate homogeneous and isotropic oscillating cosmologies with multiple fluid components. Transfer of energy between these fluids is included in order to model the effects of non-equilibrium behavior on closed universes. We find exact solutions which display a range of new behaviors for the expansion scale factor. Detailed examples are studied for the exchange of energy from dust or scalar field into radiation. We show that, contrary to expectation, it is unlikely that such models can offer a physically viable solution to the flatness problem.
The Ups and Downs of Alpha Centauri  [PDF]
Thomas R. Ayres
Physics , 2014, DOI: 10.1088/0004-6256/147/3/59
Abstract: The following is a progress report on the long-term coronal activity of Alpha Centauri A (HD128620: G2V) and B (HD128621: K1V). Since 2005, Chandra X-ray Observatory has carried out semiannual pointings on AB, mainly with the High Resolution Camera (HRC-I), but also on two occasions with the Low-Energy Transmission Grating Spectrometer (LETGS), fully resolving the close pair in all cases. During 2008-2013, Chandra captured the rise, peak, and initial decline of B's coronal luminosity. Together with previous high states documented by ROSAT and XMM-Newton, the long-term X-ray record suggests a period of 8.2+/-0.2 yr, compared to 11 yr for the Sun; with a minimum-to-peak contrast of 4.5, about half the typical solar cycle amplitude. Meanwhile, the A component has been mired in a Maunder-Minimum-like low state since 2005, initially recognized by XMM. But now, A finally appears to be climbing out of the extended lull. If interpreted simply as an over-long cycle, the period would be 19.1+/-0.7 yr, with a minimum-to-peak contrast of 3.4. The short X-ray cycle of B, and possibly long cycle of A, are not unusual compared with the diverse (albeit much lower amplitude) chromospheric variations recorded, for example, by the HK Project. Further, the deep low state of A also is not unusual, but instead is similar to the Sun during recent minima of the sunspot cycle.
Squeezing: the ups and downs  [PDF]
K. Gorska,A. Horzela,F. H. Szafraniec
Mathematics , 2014, DOI: 10.1098/rspa.2014.0205
Abstract: We present an operator theoretic side of the story of squeezed states regardless the order of squeezing. For low order, that is for displacement (order 1) and squeeze (order 2) operators, we bring back to consciousness what is know or rather what has to be known by making the exposition as exhaustive as possible. For the order 2 (squeeze) we propose an interesting model of the Segal-Bargmann type. For higher order the impossibility of squeezing in the traditional sense is proved rigorously. Nevertheless what we offer is the state-of-the-art concerning the topic.
Ups and Downs in Pollinator Populations: When is there a Decline?  [cached]
David Ward Roubik
Ecology and Society , 2001,
Abstract: Plant-pollinator systems inherently possess wide variation that limits the applicability of surveys on population dynamics or diversity. Stable habitats are scarcely studied, whereas dynamics in unprotected habitats are less predictable or more compromised by exotic organisms (Apis, in the case of bee surveys). An extensively replicated, long-term study of orchid-bees (Euglossini) was made in protected tropical moist forest in Panama. Over 47,000 bees were recorded in 124 monthly censuses employing 1952 counts. No aggregate trend in abundance occurred (from 1979 to 2000), although four individual species declined, nine increased, 23 showed no change, and species richness was stable. No rare or parasitic species showed decreasing trends, while the most common of the set of bee species studied gradually declined. Biodiversity therefore increased. Recorded variability included 300% (fourfold) differences in bee abundance among years, and changes in species abundance up to 14-fold. Surveys in dry and wet seasons (N = 17 and 18 years, 29 and 31 species, respectively) indicated no numerical changes in the bee assemblage over 21 years. El-Ni o climatic events led to brief increases in bee abundance. This detailed survey is deconstructed to assess sampling rigor and strategies, particularly considering the recorded local differences within a single forest. Year-to-year shifts in bee abundance for three tropical and five temperate bee censuses were comparable. In short studies (2-4 years) and during longer studies (17-21 years), 59 species that included solitary, social, and highly social bees had mean abundances that varied by factors of 2.06 for temperate bees and 2.16 for tropical bees. “Normal” bee populations commonly halved or doubled in 1-yr intervals. Longer term data are only available for the tropics. Stochastic variation and limitations of monitoring methods suggest that minimum series of four years (i.e., three intervals) of several counts during the active season may demonstrate genuine trends. Longer term, continuous studies are still needed for meaningful insights on pollinator population shifts in nature.
Ups and Downs of Viagra: Revisiting Ototoxicity in the Mouse Model  [PDF]
Adrian Au, John Gerka Stuyt, Daniel Chen, Kumar Alagramam
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0079226
Abstract: Sildenafil citrate (Viagra), a phosphodiesterase 5 inhibitor (PDE5i), is a commonly prescribed drug for erectile dysfunction. Since the introduction of Viagra in 1997, several case reports have linked Viagra to sudden sensorineural hearing loss. However, these studies are not well controlled for confounding factors, such as age and noise-induced hearing loss and none of these reports are based on prospective double-blind studies. Further, animal studies report contradictory data. For example, one study (2008) reported hearing loss in rats after long-term and high-dose exposure to sildenafil citrate. The other study (2012) showed vardenafil, another formulation of PDE5i, to be protective against noise-induced hearing loss in mice and rats. Whether or not clinically relevant doses of sildenafil citrate cause hearing loss in normal subjects (animals or humans) is controversial. One possibility is that PDE5i exacerbates age-related susceptibility to hearing loss in adults. Therefore, we tested sildenafil citrate in C57BL/6J, a strain of mice that displays increased susceptibility to age-related hearing loss, and compared the results to those obtained from the FVB/N, a strain of mice with no predisposition to hearing loss. Six-week-old mice were injected with the maximum tolerated dose of sildenafil citrate (10 mg/kg/day) or saline for 30 days. Auditory brainstem responses (ABRs) were recorded pre- and post injection time points to assess hearing loss. Entry of sildenafil citrate in the mouse cochlea was confirmed by qRT-PCR analysis of a downstream target of the cGMP-PKG cascade. ABR data indicated no statistically significant difference in hearing between treated and untreated mice in both backgrounds. Results show that the maximum tolerated dose of sildenafil citrate administered daily for 4 weeks does not affect hearing in the mouse. Our study gives no indication that Viagra will negatively impact hearing and it emphasizes the need to revisit the issue of Viagra related ototoxicity in humans.
The Far-Ultraviolet Ups and Downs of Alpha Centauri  [PDF]
Thomas R. Ayres
Physics , 2014,
Abstract: Four years (2010-2014) of semiannual pointings by Hubble Space Telescope Imaging Spectrograph (STIS) on nearby Alpha Centauri have yielded a detailed time history of far-ultraviolet emissions of the solar-like primary (A: G2V) and the cooler, but more active, secondary (B: K1V). This period saw A climbing out of a prolonged coronal X-ray minimum, as documented by Chandra, while B was rising to, then falling from, a peak of its long-term (8 yr) starspot cycle. The FUV fluxes of the primary were steady over most of the STIS period, although the [Fe XII] 124 nm coronal forbidden line (T= 1.5 MK) partly mirrored the slowly rising X-ray fluxes. The FUV emissions of the secondary more closely tracked the rise and fall of its coronal luminosities, especially the "hot lines" like Si IV, C IV, and N V (T= 80,000-200,000 K), and coronal [Fe XII] itself. The hot lines of both stars were systematically redshifted, relative to narrow chromospheric emissions, by several km/s, showing little change in amplitude over the 4-year period; especially for Alpha Cen B, despite the significant evolution of its coronal activity. Further, the hot line profiles of both stars, individually and epoch-averaged, could be decomposed into two nearly equal components, one narrow (FWHM~ 25-45 km/s), the other broad (60-80 km/s). Not much variation of the component properties was seen over the 4-year period, even over the major cycle changes of B. This suggests that there is a dominant "quantum" of FUV surface activity that is relatively unchanged during the cycle, aside from the fractional area covered.
The `Ups' and `Downs' of a Spinning Black Hole  [PDF]
Chris M. Chambers,William A. Hiscock,Brett E. Taylor
Physics , 1997,
Abstract: We report and comment upon the principal results of an investigation into the evolution of rotating black holes emitting massless scalar radiation via the Hawking process. It is demonstrated that a Kerr black hole evaporating by the emission of scalar radiation will evolve towards a state with $a \approx 0.555M$. If the initial specific angular momentum is larger than this value the hole will spin down to this value; if it is less it will spin up to this value. The addition of higher spin fields to the picture strongly suggests the final asymptotic state of a realistic evaporation process will be characterized by an $a/M = 0$.
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