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Is a Multipolar World a Concern to International Law?
Get PDFAdjunct Professor Remiguis Chibueze, Attorney at Law; Adjunct Professor of Law, Golden Gate University School of Law
Morning Session
No full textMaster of Ceremonies: Professor Dr. Remigius Chibueze, Attorney at Law; Adjunct Professor of Law, Golden Gate University School of Law.
Dr. Chibueze is in private practice in Oakland and serves as a consultant to some Nigerian companies with business interests in the United States. Dr. Chibueze teaches Jessup International Law Moot Court Competition, SJD Dissertation Seminar, and International Investment Law at Golden Gate University School of Law. Dr. Chibueze also taught Intellectual Property Seminar at John F. Kennedy University School of Law. He is a member of the California State Bar and Solicitor and Advocate of the Supreme Court of Nigeria. He has published academic works in International Law, International Commercial Arbitration and International Criminal Law. His research areas include International Law, International Criminal Law, International Human Rights Law, International Commercial Arbitration, and International Intellectual Property Law.
Welcome: Dr. Dan Angel, President of Golden Gate University.
Dr. Dan Angel was appointed President of Golden Gate University in January of 2007 and has steadily moved the university forward. Late in 2010 he was awarded a most admired CEO award by the Bay Area’s Business Times. His career includes five other Presidencies: Marshall University (WV), Stephen F. Austin University (TX), Austin Community College (TX), Citrus College (CA) and Imperial Valley College (CA). He was elected to the State Legislature in Michigan and served as a Special Assistant to a U.S. Senator in Washington D.C. His university teaching experience includes Purdue University, Wayne State University, the University of Delaware, Albion College and Queens College in NYC. A prolific writer, he has published 12 books including a political biography of former Michigan Governor George Romney, a primer on long range planning, and a book on management. He and the Dean of the Ageno School of Business, Terry Connelly, have just finished a book – RIPTIDE: The New Normal for Higher Education, to be published later this spring. His educational credentials include a BS and MA (Education) from Wayne State University and a PhD earned at Purdue (Communications). Major public service assignments have included membership on the Federal Reserve Board (Dallas). Career honors include: Distinguished Alumnus at Wayne State University (Michigan), Public Administrator of the Year (Austin, TX) and an invitation to the Oxford Roundtable (England)
A heatwave of accretion energy traced by masers in the G358-MM1 high-mass protostar
No full textHigh-mass stars are thought to accumulate much of their mass via short, infrequent bursts of disk-aided accretion1,2. Such accretion events are rare and difficult to observe directly but are known to drive enhanced maser emission3,4,5,6. In this Letter we report high-resolution, multi-epoch methanol maser observations toward G358.93-0.03, which reveal an interesting phenomenon: the subluminal propagation of a thermal radiation ‘heatwave’ emanating from an accreting high-mass protostar. The extreme transformation of the maser emission implies a sudden intensification of thermal infrared radiation from within the inner (40-mas, 270-au) region. Subsequently, methanol masers trace the radial passage of thermal radiation through the environment at ≥4% of the speed of light. Such a high translocation rate contrasts with the ≤10 km s−1 physical gas motions of methanol masers typically observed using very-long-baseline interferometry (VLBI). The observed scenario can readily be attributed to an accretion event in the high-mass protostar G358.93-0.03-MM1. While being the third case in its class, G358.93-0.03-MM1 exhibits unique attributes hinting at a possible ‘zoo’ of accretion burst types. These results promote the advantages of maser observations in understanding high-mass-star formation, both through single-dish maser monitoring campaigns and via their international cooperation as VLBI array
Detection of new methanol maser transitions associated with G358.93−0.03
Get PDFWe report the detection of new 12.178, 12.229, 20.347, and 23.121 GHz methanol masers in the massive star-forming region G358.93−0.03, which are flaring on similarly short time-scales (days) as the 6.668 GHz methanol masers also associated with this source. The brightest 12.178 GHz channel increased by a factor of over 700 in just 50 d. The masers found in the 12.229 and 20.347 GHz methanol transitions are the first ever reported and this is only the fourth object to exhibit associated 23.121 GHz methanol masers. The 12.178 GHz methanol maser emission appears to have a higher flux density than that of the 6.668 GHz emission, which is unusual. No associated near-infrared flare counterpart was found, suggesting that the energy source of the flare is deeply embedde
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
VLBI observations of the G25.65+1.05 water maser superburst
No full textThis paper reports observations of a 22 GHz water maser ‘superburst’ in the G25.65+1.05 massive star-forming region, conducted in response to an alert from the Maser Monitoring Organisation (M2O). Very long baseline interferometry (VLBI) observations using the European VLBI Network (EVN) recorded a maser flux density of 1.2 × 104 Jy. The superburst was investipgated in the spectral, structural, and temporal domains and its cause was determined to be an increase in maser path length generated by the superposition of multiple maser emitting regions aligning in the line of sight to the observer. This conclusion was based on the location of the bursting maser in the context of the star-forming region, its complex structure, and its rapid onset and deca
Bow shocks in a newly discovered maser source in IRAS 20231+3440
Get PDFFrom measuring the annual parallax of water masers over 1.5 yr with VLBI Exploration of
Radio Astrometry, we present the trigonometric parallax and corresponding distance of another
newly identified water maser source in the region of IRAS 20231+3440 as π = 0.611 ± 0.022
mas and D=1.64±0.06 kpc, respectively.We measured the absolute proper motions of all the
newly detected maser spots (30 spots) and presented two pictures describing the possible spatial
distribution of the water maser as the morphology marks out an arc of masers whose average
proper motion velocity in the jet direction was 14.26 km s−1. As revealed by the ALLWISE
composite image and by applying the colour–colour method of young stellar objects (YSO)
identification and classification on photometric archived data, we identified the driving source
of the north maser group to be a class I, young stellar object. To further probe the nature of
the progenitor, we used the momentum rate maximum value (1.2×10−4 M yr−1 km s−1)
of the outflow to satisfy that the progenitor under investigation is a low-mass young stellar
object concurrently forming alongside an intermediate-mass YSO ∼60 000 au (∼37 arcsec)
away from i
The extraordinary outburst in the massive protostellar system NGC 6334I-MM1: flaring of the water masers in a north-south bipolar outflow driven by MM1B
No full textWe compare multi-epoch sub-arcsecond Very Large Array imaging of the 22 GHz water masers toward the massive protocluster NGC 6334I observed before and after the recent outburst of MM1B in (sub)millimeter continuum. Since the outburst, the water maser emission toward MM1 has substantially weakened. Simultaneously, the strong water masers associated with the synchrotron continuum point source CM2 have flared by a mean factor of 6.5 (to 4.2 kJy) with highly blueshifted features (up to 70 km s−1 from the LSR) becoming more prominent. The strongest flaring water masers reside 3000 au north of MM1B and form a remarkable bow shock pattern whose vertex coincides with CM2 and tail points back to MM1B. Excited OH masers trace a secondary bow shock located ~120 au downstream. Atacama Large Millimeter Array images of CS (6–5) reveal a highly collimated north–south structure encompassing the flaring masers to the north and the nonflaring masers to the south seen in projection toward the MM3-UCHII region. Proper motions of the southern water masers over 5.3 years indicate a bulk projected motion of 117 km s−1 southward from MM1B with a dynamical time of 170 years. We conclude that CM2, the water masers, and many of the excited OH masers trace the interaction of the high-velocity bipolar outflow from MM1B with ambient molecular gas. The previously excavated outflow cavity has apparently allowed the radiative energy of the current outburst to propagate freely until terminating at the northern bow shock where it strengthened the masers. Additionally, water masers have been detected toward MM7 for the first time, and a highly collimated CS (6–5) outflow has been detected toward MM
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