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141.
142.
We investigate the impact of the Petermann-excess-noise factor K>/=1 on the possibility of intensity noise squeezing of laser light below the standard quantum limit. Using an N-mode model, we show that squeezing is limited to a floor level of 2(K-1) times the shot noise limit. Thus, even a modest Petermann factor significantly impedes squeezing, which becomes impossible when K>/=1.5. This appears as a serious limitation for obtaining sub-shot-noise light from practical semiconductor lasers. We present experimental evidence for our theory.  相似文献   
143.
While a relationship in a social or business network should be mutually beneficial, it is ambiguous whether the relationship benefits or harms the rest of the network. This paper focuses on the situation where any new relationship imposes a negative externality on the rest of the network. We model this by assuming an agent’s payoff from a relationship is a decreasing function of the number of relationships the other agent maintains. We solve for the socially efficient and stable networks. While in general the two diverge, we demonstrate that they coincide when agents are able to make transfers to their partners.  相似文献   
144.
Dysphonia and airway obstruction are rarely caused by Kaposi's Sarcoma (KS). We present the case of a 40 year old man receiving his diagnosis of human immunodeficiency virus (HIV) after presenting with hoarseness caused by laryngeal KS. HIV may contribute to KS growth by stimulating excess production of angiogenic lymphokines and monokines and by decreasing immune surveillance. Histopathology reveals proliferating endothelial cells, fibroblasts, thin vascular slits, and extravasated erythrocytes. A wide variety of localized treatment options exist, while chemotherapeutic agents and alpha-interferon are used for multifocal or widespread disease.  相似文献   
145.
Although treatment with botulinum toxin type A (BTXA) has become the standard of care for most patients with laryngeal dystonia, its use is limited by the development of resistance to the toxin in some patients. Botulinum toxin type B (BTXB) has been found to be safe and effective in the treatment of cervical dystonia, but it has not been used previously to treat spasmodic dysphonia. Our experience with BTXB in a patient who developed resistance to BTXA suggests that BTXB may be safe and effective for the treatment of laryngeal dystonia, as well.  相似文献   
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