A metapopulation model for whale-fall specialists: The largest whales are essential to prevent species extinctions

The sunken carcasses of great whales (i.e., whale falls) provide an important deep-sea habitat for more than 100 species that may be considered whale-fall specialists. Commercial whaling has reduced the abundance and size of whales, and thus whale-fall habitats, as great whales were hunted and removed from the oceans, often to near extinction. In this article, we use a metapopulation modeling approach to explore the consequences of whaling to the abundance and persistence of whale-fall habitats in the deep sea and to the potential for extinction of whale-fall specialists. Our modeling indicates that the persistence of metapopulations of whale-fall specialists is linearly related to the abundance of whales, and extremely sensitive (to the fourth power) to the mean size of whales. Thus, whaling-induced declines in the mean size of whales are likely to have been as important as declines in whale abundance to extinction pressure on whale-fall specialists. Our modeling also indicates that commercial whaling, even under proposed sustainable yield scenarios, has the potential to yield substantial extinction of whale-fall specialists. The loss of whale-fall habitat is likely to have had the greatest impact on the diversity of whale-fall specialists in areas where whales have been hunted for centuries, allowing extinctions to proceed to completion. The North Atlantic experienced dramatic declines, and even extirpation, of many whale species before the 20th century; thus, extinctions of whale-fall specialists are likely to have already occurred in this region. Whale depletions have occurred more recently in the Southern Hemisphere and across most of the North Pacific; thus, these regions may still have substantial extinction debts, and many extant whale-fall specialists may be destined for extinction if whale populations do not recover in abundance and mean size over the next few decades. Prior to the resumption of commercial whaling, or the loosening of protections to reduce incidental take, the impacts of hunting on deep-sea whale-fall ecosystems, as well as differential protection of the largest whales within and across species, should be carefully considered

Clinical population pharmacokinetics and toxicodynamics of linezolid

Thrombocytopenia is a common side effect of linezolid, an oxazolidinone antibiotic often used to treat multidrug-resistant Gram-positive bacterial infections. Various risk factors have been suggested, including linezolid dose and duration of therapy, baseline platelet counts, and renal dysfunction; still, the mechanisms behind this potentially treatment-limiting toxicity are largely unknown. A clinical study was conducted to investigate the relationship between linezolid pharmacokinetics and toxico-dynamics and inform strategies to prevent and manage linezolid-associated toxicity. Forty-one patients received 42 separate treatment courses of linezolid (600 mg every 12 h). A new mechanism-based, population pharmacokinetic/toxicodynamic model was developed to describe the time course of plasma linezolid concentrations and platelets. A linezolid concentration of 8.06 mg/ liter (101% between-patient variability) inhibited the synthesis of platelet precursor cells by 50%. Simulations predicted treatment durations of 5 and 7 days to carry a substantially lower risk than 10- to 28-day therapy for platelet nadirs o

Russia, the United States, and the Caucasus

In the post-Soviet period, the Caucasus region has been a source of chronic instability and conflict. Many factors have ensured that the region would become a source of significant international engagement and concern. Conflicting interests that have made Russian-American relations in the region highly competitive are addressed as well as areas of shared priorities and mutual advantage that may provide a foundation for containing conflict and heading off further regional disintegration. However they are resolved, regional issues emerging from the Caucasus will have a significant impact upon the larger climate of U.S.-Russian relations in the years to come.https://press.armywarcollege.edu/monographs/1692/thumbnail.jp

War in the Balkans, 1991-2002

The author writes a comprehensive history of the Balkan wars which were provoked by the collapse of the Yugoslav Federation in 1991. These wars, and the instability that they have provoked, became preoccupations for international security management through the 1990s. After an initial phase of distancing and hesitation, Balkan conflict drew the United States and its most important European allies into an open-ended commitment to peace enforcement, conflict management, and peace-building in the region, importantly supported by the U.S. Army. These efforts are still underway, and significant tensions and potential flashpoints remain in place within former Yugoslavia and the entire Southeastern European area. The lessons learned from the new Balkan wars, and the successes and failures of U.S. and international engagement, will be a significant foundation for future efforts to manage intractable regional conflict. The Balkan conflict of the 1990s, as a case study in state failure and medium intensity warfare, international conflict management and intervention, and U.S. military engagement, provides an excellent framework for asking basic questions about the dynamic of international security at the dawn of a new millennium. War in the Balkans, 1991-2002 is intended to provide a foundation for addressing such questions by surveying events in both contemporary and larger historical perspectives and posing preliminary conclusions concerning their larger meaning. There will, regretfully, be other situations comparable in broad outline to the violent decline and fall of socialist Yugoslavia. The policies of the international community in the Yugoslav imbroglio have been criticized widely as ineffective. However, in the end, after years of futility, the conflict could be contained only by a significant international military intervention spearheaded by the United States, and a long-term, multilateral commitment to post-conflict peace-building.https://press.armywarcollege.edu/monographs/1037/thumbnail.jp

War in the Balkans, 1991-2002

The author writes a comprehensive history of the Balkan wars which were provoked by the collapse of the Yugoslav Federation in 1991. These wars, and the instability that they have provoked, became preoccupations for international security management through the 1990s. After an initial phase of distancing and hesitation, Balkan conflict drew the United States and its most important European allies into an open-ended commitment to peace enforcement, conflict management, and peace-building in the region, importantly supported by the U.S. Army. These efforts are still underway, and significant tensions and potential flashpoints remain in place within former Yugoslavia and the entire Southeastern European area. The lessons learned from the new Balkan wars, and the successes and failures of U.S. and international engagement, will be a significant foundation for future efforts to manage intractable regional conflict. The Balkan conflict of the 1990s, as a case study in state failure and medium intensity warfare, international conflict management and intervention, and U.S. military engagement, provides an excellent framework for asking basic questions about the dynamic of international security at the dawn of a new millennium. War in the Balkans, 1991-2002 is intended to provide a foundation for addressing such questions by surveying events in both contemporary and larger historical perspectives and posing preliminary conclusions concerning their larger meaning. There will, regretfully, be other situations comparable in broad outline to the violent decline and fall of socialist Yugoslavia. The policies of the international community in the Yugoslav imbroglio have been criticized widely as ineffective. However, in the end, after years of futility, the conflict could be contained only by a significant international military intervention spearheaded by the United States, and a long-term, multilateral commitment to post-conflict peace-building.https://press.armywarcollege.edu/monographs/1087/thumbnail.jp

The United States and Russia into the 21st Century

In late April 1997, the U.S. Army War College\u27s Strategic Studies Institute hosted its Eighth Annual Strategy Conference. The topic for this year\u27s conference was Russia\u27s Future as a World Power. The concluding panel for this conference, The United States and Russia into the 21st Century, included the following two papers. In the first essay, Beyond the Cold War: Change and Continuity in U.S.-Russian Relations, Dr. R. Craig Nation argues that, for the United States, the primary challenge is to adjust to a post-Cold War world where it is difficult to justify traditional exercises of power in the absence of any imminent threat. But, for the United States, the trauma of readjustment has been mostly confined to the American defense industry and the military services themselves; and the adjustments that are being undertaken have occurred in the midst of an economy enjoying an exceptionally long and steady growth. For Russia, however, the demise of the Soviet Union was a event of unparalleled historical precedent. In the span of a few years, what was once an awesome empire, one whose interests were defended by armed forces of tremendous size and quality, fractured. Left was a truncated state, undergoing massive economic upheaval. With the exception of its armed forces and nuclear capabilities, Russia poses dangers to only a very few immediate neighbors. Dr. Nation traces the attempts of both states to come to terms with Russia\u27s new status and to establish a new relationship. He concludes that neither a purely cooperative nor inevitably antagonistic pattern will characterize their turn-of-the- century interaction. Instead, we should anticipate a hybrid model as Russia defines its national interests through its own prism. In the second essay, American Policy Towards Russia: Framework for Analysis and Guide to Action, Dr. Michael McFaul maintains that, while Russia may be temporarily in decline, its sheer size, natural resources, educated populace, and strategic locationhttps://press.armywarcollege.edu/monographs/1178/thumbnail.jp