788 research outputs found
A simple model potential for hollow nanospheres
A new model potential is introduced to describe the hollow nanospheres such
as fullerene and molecular structures and to obtain their electronic
properties. A closed analytical solution of the corresponding treatment is
given within the framework of supersymmetric perturbation theory.Comment: 7 pages, 3 figure
Comparative analysis of the Mexican and Turkish currency crises
Author's OriginalThe study aims to explore characteristics of currency crises in emerging markets. Two recent experiences in Mexico and Turkey respectively analyzed carefully to identify common elements in the development and eruption of the crises. Results of the study suggest that there are several background factors and triggers that were consistent in both cases. Finally a discussion of the policy implications of the findings concludes the study.Aybar, C., Ajami, R., & Bear, M. (2000). Currency crises in emerging markets: A comparative analysis of the Mexican and Turkish cases. International Journal of Public Administration, 23(5-8), 963-1006
The Supernova Remnant CTB104A : Magnetic Field Structure and Interaction with the Environment
We present new, high resolution 1420 and 408 MHz continuum images and HI and
12CO (J=1-0) spectral line maps of the diffuse supernova remnant CTB104A
(G93.7-0.3). Analysis of the complex continuum emission reveals no significant
spectral index variations across the remnant. Three prominences around CTB104A
are found to be related to the SNR, while one extension to the east is
identified as an HII region associated with a background molecular shell. Small
scale polarization and rotation measure (RM) structures are turbulent in
nature, but we find a well-ordered RM gradient across the remnant, extending
from southeast to northwest. This gradient does not agree with the direction of
the global Galactic magnetic field, but does agree with a large-scale RM
anomaly inferred from rotation measure data by Cleg et al. (1992). We show that
the observed morphology of CTB104A is consistent with expansion in a uniform
magnetic field, and this is supported by the observed RM distribution. By
modeling the RM gradient with a simple compression model we have determined the
magnetic field strength within the remnant as Bo ~ 2.3 micro G. We have
identified signatures of the interaction of CTB104A with the surrounding
neutral material, and determined its distance, from the kinematics of the HI
structure encompassing the radio emission, as 1.5 kpc. We also observed clear
breaks in the HI shell that correspond well to the positions of two of the
prominences, indicating regions where hot gas is escaping from the interior of
the SNR.Comment: 7 pages, Latex with aastex and emulateapj5, 12 figures, ApJ accepte
Group Scheduling in a Cellular Manufacturing Shop to Minimise Total Tardiness and nT: a Comparative Genetic Algorithm and Mathematical Modelling Approach
In this paper, family and job scheduling in a cellular manufacturing shop is addressed where jobs have individual due dates. The objectives are to minimise total tardiness and the number of tardy jobs. Family splitting among cells is allowed but job splitting is not. Two optimisation methods are employed in order to solve this problem, namely mathematical modelling (MM) and genetic algorithm (GA). The results showed that GA found the optimal solution for most of the problems with high frequency. Furthermore, the proposed GA is efficient compared to the MM especially for larger problems in terms of execution times. Other critical aspects of the problem such as family preemption only, impact of family splitting on common due date scenarios and dual objective scenarios are also solved. In short, the proposed comparative approach provides critical insights for the group scheduling problem in a cellular manufacturing shop with distinctive cases
COVID-19 and the Quest for Reconfiguration of Disciplines: Unpacking New Directions
This theoretical editorial piece sets the tone for a special issue that focuses on teasing new directions during and after the COVID-19 pandemic. The piece is underpinned by bricolage thinking, and we seek to show that it is essential to reimagine various educational disciplines in order to meet new challenges and opportunities presented by COVID-19. In doing so, we are convinced that the relationship between a serene scholarly quest and applied space has to be re-examined. Thus, to reimagine a better world during and post COVID-19, cross-disciplinarity is no longer an option for humanity, instead, it is essential, to ensure the collective efforts needed to address the pressing issues of the day. We end this editorial section by arguing that new strategies that are adopted need to be shared across disciplines and faculties, to reinvent multidisciplinary or interdisciplinary approaches to addressing human crises
The distance to the SNR CTB109 deduced from its environment
We conducted a study of the environment around the supernova remnant CTB109.
We found that the SNR is part of a large complex of HII regions extending over
an area of 400 pc along the Galactic plane at a distance of about 3 kpc at the
closer edge of the Perseus spiral arm. At this distance CTB109 has a diameter
of about 24 pc. We demonstrated that including spiral shocks in the distance
estimation is an ultimate requirement to determine reliable distances to
objects located in the Perseus arm. The most likely explanation for the high
concentration of HII regions and SNRs is that the star formation in this part
of the Perseus arm is triggered by the spiral shock.Comment: 6 pages, 6 figures. accepted for publication in the Astrophysical
Journa
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Knowing loved ones' end-of-life health care wishes: Attachment security predicts caregivers' accuracy.
Objective: At times, caregivers make life-and-death decisions for loved ones. Yet very little is known about the factors that make caregivers more or less accurate as surrogate decision makers for their loved ones. Previous research suggests that in low stress situations, individuals with high attachment-related anxiety are attentive to their relationship partners' wishes and concerns, but get overwhelmed by stressful situations. Individuals with high attachment-related avoidance are likely to avoid intimacy and stressful situations altogether. We hypothesized that both of these insecure attachment patterns limit surrogates' ability to process distressing information and should therefore be associated with lower accuracy in the stressful task of predicting their loved ones' end-of-life health care wishes. Method: Older patients visiting a medical clinic stated their preferences toward end-of-life health care in different health contexts, and surrogate decision makers independently predicted those preferences. For comparison purposes, surrogates also predicted patients' perceptions of everyday living conditions so that surrogates' accuracy of their loved ones' perceptions in nonstressful situations could be assessed. Results: Surrogates high on either type of insecure attachment dimension were less accurate in predicting their loved ones' end-of-life health care wishes. It is interesting to note that even though surrogates' attachment-related anxiety was associated with lower accuracy of end-of-life health care wishes of their loved ones, it was associated with higher accuracy in the nonstressful task of predicting their loved ones' everyday living conditions. Conclusions: Attachment orientation plays an important role in accuracy about loved ones' end-of-life health care wishes. Interventions may target emotion regulation strategies associated with insecure attachment orientations
Catastrophic secondary antiphospholipid syndrome with peripheral nervous system involvement: a case report.
A 34-year-old woman was admitted to our emergency room with a high fever, abdominal pain, dyspnea and confusion. High fever and abdominal pain had first occured after a cystocele operation 5 months earlier. Later, congestive heart failure with mural thrombus formation, peripheral polyneuropathy and ischemic cerebrovascular accident were identified in clinical follow-ups, and multiple arterial and venous thromboses were seen on cranial and abdominal magnetic resonance imaging angiography. The patient's symptoms improved with anticoagulant treatment. Antiphospholipid syndrome with elevated serum anticardiolipin IgG levels was diagnosed, and ischemic peripheral polyneuropathy with axonal degeneration was determined by sural nerve biopsy. In antiphospholipid syndrome, elevated anticardiolipin antibodies appear to be the most common acquired blood protein defect causing thrombosis. Disseminated vascular thrombosis in catastrophic antiphospholipid syndrome can result in multiorgan failure with increased morbidity and mortality. It rarely occurs secondary to various infections as in the case of our patient, who suffered postoperative intraabdominal infection. It is important to note that peripheral nervous system involvement is rare in antiphospholipid syndrome.</p
Combined surgical treatment for missed rupture of triceps tendon associated with avulsion of the ulnar collateral ligament and flexor-pronator muscle mass
Triceps tendon ruptures are rare injuries. Coexistence of ipsilateral ulnar collateral ligament injury is even rarer. Here, we describe an unusual combination injury to elbow of a 39-year-old male construction worker consisting of triceps tendon rupture, avulsion of elbow ulnar collateral ligament and flexor pronator muscle origin ipsilaterally. A simultaneous repair and reconstruction of all damaged structures was proposed with individualized postoperative rehabilitation. Return to pre-injury level of activities obtained with this treatment protocol. High degree of suspicion and careful examination were needed to prevent missed diagnosis and prolonged instability which may be inevitable after inappropriate treatment of such injury
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