2,121 research outputs found
Basal Chromospheric Flux and Maunder Minimum-type Stars: The quiet-Sun Chromosphere as a Universal Phenomenon
Aims: We demonstrate the universal character of the quiet-Sun chromosphere
among inactive stars (solar-type and giants). By assessing the main physical
processes, we shed new light on some common observational phenomena. Methods:
We discuss measurements of the solar Mt. Wilson S-index, obtained by the
Hamburg Robotic Telescope around the extreme minimum year 2009, and compare the
established chromospheric basal Ca II K line flux to the Mt. Wilson S-index
data of inactive ("flat activity") stars, including giants. Results: During the
unusually deep and extended activity minimum of 2009, the Sun reached S-index
values considerably lower than in any of its previously observed minima. In
several brief periods, the Sun coincided exactly with the S-indices of inactive
("flat", presumed Maunder Minimum-type) solar analogues of the Mt. Wilson
sample; at the same time, the solar visible surface was also free of any plages
or remaining weak activity regions. The corresponding minimum Ca II K flux of
the quiet Sun and of the presumed Maunder Minimum-type stars in the Mt. Wilson
sample are found to be identical to the corresponding Ca II K chromospheric
basal flux limit. Conclusions: We conclude that the quiet-Sun chromosphere is a
universal phenomenon among inactive stars. Its mixed-polarity magnetic field,
generated by a local, "fast" turbulent dynamo finally provides a natural
explanation for the minimal soft X-ray emission observed for inactive stars.
Given such a local dynamo also works for giant chromospheres, albeit on larger
length scales, i.e., l ~ R/g, with R and g as stellar radius and surface
gravity, respectively, the existence of giant spicular phenomena and the
guidance of mechanical energy toward the acceleration zone of cool stellar
winds along flux-tubes have now become traceable.Comment: 6 pages, 4 figures; Astronomy & Astrophysics (Research Note), in
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Asymmetric Price Responses and the Underlying Energy Demand Trend: Are they Substitutes or Complements? Evidence from Modelling OECD Aggregate Energy Demand
A number of energy demand studies have considered the importance of modelling Asymmetric Price Responses (APR), for example, the often-cited work of Gately and Huntington (2002). Griffin and Schulman (2005) questioned the asymmetric approach arguing that this is only capturing energy saving technical progress. Huntington (2006), however, showed that for whole economy aggregate energy and oil demand there is a role statistically for both APR and exogenous energy saving technical change. In a separate strand of the literature the idea of the Underlying Energy Demand Trend (UEDT) has been developed, see for example Hunt et al. (2003a and 2003b) and Dimitropoulos et al. (2005). They argue that it is important, in time series energy demand models, to allow for stochastic trends (or UEDTs) based upon the structural time series/dynamic regression methodology recommended by Harvey (1989, 1997). This paper attempts to bring these strands of the literature together by conducting tests for the UEDT and APR in energy demand models within both a panel context (consistent with the Huntington, 2006 approach) and the structural time series modelling framework. A set of tests across a range of specifications using time-series and panel data are therefore undertaken in order to ascertain whether energy saving technical change (or the more general UEDT) and APR are substitutes for each other when modelling energy demand or whether they are actually picking up different influences and are therefore complements. Using annual whole economy data for 17 OECD countries over the period 1960 – 2004 the results suggest that in general the UEDT and ARP are complementary estimation methodologies when modelling aggregate energy demand. It is argued therefore that energy demand modellers should not assume at the outset that one method is superior to the other. Moreover, wherever possible, a general model (be it in a time series or panel context) that includes a ‘non linear UEDT’ and APR should be initially estimated, and only if accepted by the data should symmetry and/or a more restrictive UEDT be imposed.Energy Demand, OECD, Asymmetric Price Responses, Underlying Energy Demand Trend.
Kajian Pasal 76 Undang-undang Nomor 15 Tahun 2001 Tentang Merek dan Hubungannya dengan USAha Mikro Kecil Menengah
Brand protection is an important thing, remember rapid growth of world trade today. But here are still many perpetrators of Micro, Small and Medium Enterprises who do not know will the importance of brand protection, so there is still plenty of them which are in violation of that Article. Many perpetrators of Small and Medium Enterprises who commit violations in the brand the products it produces it is to install brands that are well known in the products into the big question about the socialization conducted regarding the importance of IPR, which is how the existence of Article 76 of the Law No. 15 of 2001 on Marks in the Micro, Small and Medium and how constraints in the implementation of Article 76 Law No. 15 of 2001 on Marks and do the Micro, Small and Medium Enterprises as well as how efforts completion. By using descriptive research namely analysis means investigating an incident to illustrate the real situation and what was described clearly and detailed through library research and interviews to officials authorities. In this study, a lot of violations The article caused by previous offenders Micro Small and Medium Enterprises to register for its brand on the Director General IPR due to some constraints. These constraints can come from external or derived from internal. In practice also Article 76 of Law Law No. 15 of 2001 has not been widely used for resolve disputes between businesses with actors Micro Small and Medium Enterprises in the use of well-known brands, where the parties prefer an alternative way of solving the completion disput
Iqbal Judge (IJ) Talks to Professor Joga Singh (JS)
Iqbal Judge retired as Professor and Head, PG Department of English, PG Government College for Girls-11, Chandigarh after three decades of teaching. She now volunteers as a mentor to underprivileged young people. Her abiding interests include material production, teaching and campaigning on gender issues. She talks to Professor Joga Singh, who is an acknowledged authority on linguistics. He has been instrumental in popularizing linguistics in Punjab, with over 50 research papers and five books to his name. He has guided more than 80 research scholars. A passionate advocate of education in the mother tongue and President of the Campaign for Language Equality and Rights Trust, Delhi, Professor Singh has toured widely, debunking myths about prioritizing English medium education
What Are The Correlates of Interdisciplinary Research Impact? The Case of Corporate Governance Research
We explore the concept of interdisciplinary research impact and better understand what factors might be associated with it. Using the field of corporate governance research as a case study and linking our research impact concept to a novel measure of scholarly citation rates, we seek to understand why some corporate governance scholars are cited more than others. We first developed a comprehensive ranking of the top-100 scholars cited for their research in corporate governance and then compared that high-impact group with scholars who had published governance research that was not yet cited. We hypothesized that indicators from the social network perspective would be predictive of interdisciplinary research impact. Our data largely supported our hypotheses using this new and improved measure of research impact, and robustness tests also supported our results
Judicial Immunity under the Civil Rights Act: Here Come the Judge\u27s Defenses, 7 J. Marshall J. of Prac. & Proc. 213 (1974)
A Comparative Study of Magnetic Fields in the Solar Photosphere and Chromosphere at Equatorial and Polar Latitudes
Besides their own intrinsic interest, correct interpretation of solar surface
magnetic field observations is crucial to our ability to describe the global
magnetic structure of the solar atmosphere. Photospheric magnetograms are often
used as lower boundary conditions in models of the corona, but not data from
the nearly force-free chromosphere. National Solar Observatory's (NSO) Synoptic
Optical Long-term Investigations of the Sun VSM (Vector Spectromagnetograph)
produces full-disk line-of-sight magnetic flux images deriving from both
photospheric and chromospheric layers on a daily basis. In this paper, we
investigate key properties of the magnetic field in these two layers using more
than five years of VSM data. We find from near-equatorial measurements that the
east-west inclination angle of most photospheric fields is less than about
12{\deg}, while chromospheric fields expand in all directions to a significant
degree. Using a simple stereoscopic inversion, we find evidence that
photospheric polar fields are also nearly radial but that during 2008 the
chromospheric field in the south pole was expanding superradially. We obtain a
spatially resolved polar photospheric flux distribution up to 80{\deg} latitude
whose strength increases poleward approximately as cosine(colatitude) to the
power 9-10. This distribution would give a polar field strength of 5-6 G. We
briefly discuss implications for future synoptic map construction and modeling
Spiral strand cables subjected to high velocity fragment impact
Structural cables are widely adopted around the world in offshore construction, sports stadia, large scale bridges, Ferris wheels and suspended canopy and fabric structures. However, the robustness of such structures to blast or impact is uncertain with a particular concern related to the loss of a primary structural cable when damaged by high velocity blast fragmentation. This paper presents the first ever numerical and experimental study on commonly used high-strength steel spiral strand cables subjected to high velocity fragment impact. Spiral strand cables were impacted by 20 mm fragment simulating projectiles travelling at velocities between 200 and 1400 m/s. Complex 3D non-linear finite element models were developed and carefully compared with experimental tests. The penetration resistance of the cables and resultant damage were studied with respect to fragment impact velocity. It was found that for all the impact velocities, the fragment penetration depth was less than half of the cable diameter demonstrating a considerable amount of resilience. Considering the damage caused, the residual cable breaking strengths were estimated and found to be still higher than the minimum breaking load of an un-damaged cable. The numerical models were also able to reproduce the main features of the impact tests, including the extent of localised damage area, the fragment penetration depth and mode of individual wire failures, thus demonstrating their potential to be widely used in industry for structural resilience and robustness assessments by structural engineers
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Bortezomib Augments Natural Killer Cell Targeting of Stem-Like Tumor Cells.
Tumor cells harboring stem-like/cancer stem cell (CSC) properties have been identified and isolated from numerous hematological and solid malignancies. These stem-like tumor cells can persist following conventional cytoreductive therapies, such as chemotherapy and radiotherapy, thereby repopulating the tumor and seeding relapse and/or metastasis. We have previously shown that natural killer (NK) cells preferentially target stem-like tumor cells via non- major histocompatibility complex (MHC) restricted mechanisms. Here, we demonstrated that the proteasome inhibitor, bortezomib, augments NK cell targeting of stem cell-like tumor cells against multiple solid human tumor-derived cancer lines and primary tissue samples. Mechanistically, this was mediated by the upregulation of cell surface NK ligands MHC class I chain-related protein A and B (MICA and MICB) on aldehyde dehydrogenases (ALDH)-positive CSCs. The increased expression of MICA and MICB on CSC targets thereby enhanced NK cell mediated killing in vitro and ex vivo from both human primary tumor and patient-derived xenograft samples. In vivo, the combination of bortezomib and allogeneic NK cell adoptive transfer in immunodeficient mice led to increased elimination of CSCs as well as tumor growth delay of orthotopic glioblastoma tumors. Taken together, our data support the combination bortezomib and NK transfer as a strategy for both CSC targeting and potentially improved outcomes in clinical cancer patients
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