bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conservation Genetics of Pacific Salmon I. Temporal Changes in Allele Frequency
Authors: WAPLES ROBIN S. , TEEL DAVID J. 
Published: April 2005

Abstract:Recent reductions in the abundance of all Pacific salmon species (Oncorhynchus spp.), coupled with large increases in artificial productioq demand that careful attention be paid to genetic changes occurring in both wild and cultured populations. Analysis of electrophoretic data for chinook salmon (O. tshawytscha) from the Pacific coast of Oregon revealed substantial allele frequency changes over 24 years in hatchery, but not wild populations. Unfortunately, our understanding of the causes of this result is hampered by a lack of theoretical models designed for organisms with life history features like those of Pacific salmon. We used computer simulations to provide a context for understanding genetic changes observed in the hatchery populations.Simulation results indicated that annual fluctuations in population allele frequencies due to genetic drift can typically be expected to be several percent, with the absolute magnitude determined primarily by the effective number of spawners each year rather than the age structure. Changes over 10‐ to 25‐year periods were only slightly greater than short‐term changes (1–5 years). The magnitude of allele frequency change over time was different for juvenile and adult samples. The probability of a significant test statistic comparing allele frequencies in temporally spaced samples increased with the ratio of sample size to effective number of breeders per year. This is an important consideration for conservation biologists, who typically are concerned with populations of small effective size.Simulation results indicate that it is necessary to postulate unrealistically large selection coefficients to explain the genetic changes in the hatchery populations by natural selection. The changes observed are consistent with a pure drift model provided that the effective number of breeders was as small as about 25–50 per year. Analysis of brood stock information for the hatcheries indicates that the effective population number may indeed have been this low, although the number of returning adults was often much larger. This conclusion underlines the importance of monitoring the genetic consequences of the large‐scale artificial propagation program involving Pacific salmon.
The Florida Panther and Private Lands
Authors: MAEHR DAVID S. 
Published: April 2005

Abstract:Intensive efforts to protect Florida panther (Felis concolor coryi) habitat on private lands are essential for this endangered animal to survive. About half of the presently known occupied panther range in south Florida occurs on private lank where agricultural and urban development are increasing rapidly. Panther conservation strategies must go beyond traditional land acquisition by government and include economic programs to preserve critical landscapes on private lank.
Wildlife Conservation Outside Protected Areas—Lessons from an Experiment in Zambia
Authors: LEWIS DALE , KAWECHE GILSON B. , MWENYA ACKIM 
Published: April 2005

Abstract:Managing an area as a national park in Africa often entails dealing with human pressures from regions surrounding the protected area Dealing with these human pressures is the subject of this paper, which goes well beyond mere law enforcement to discuss the realm of traditional leadership in the village, rural socioeconomics, and the services of wildlife management by government in areas surrounding a national park.This paper describes the results of an experimental project in Zambia that sought to halt the drastic loss of elephants and rhinos to poaching in and around protected areas in the Luangwa Valley. The design of this project was to involve local residents outside national parks in wildlife protection and management activities. In addition, sustained‐yield uses of wildlife were adopted to recycle revenue shares into community development and to make the program of wildlife management financially self‐supporting.To help carry out the various tasks of protecting and developing wildlife resources, residents were trained and employed as wildlife management staff Village wildlife councils provided advice and assistance. Safari concessions yielded sufficient revenue to meet the recurrent costs of wildlife management and also generated significant earnings for local community benefits. As a result; poaching dropped dramatically, local economies were improve and village attitudes toward wildlife management and conservation became more positive.
Rarity in Neotropical Forest Mammals and Its Ecological Correlates
Authors: ARITA HÉCTOR T. , ROBINSON JOHN G. , H.REDFORD KENT 
Published: April 2005

Abstract:Local density and size of distributional range have been used to characterize rarity, but conclusions are weakened by their possible lack of independence. The usefulness and validity of using these two variables were tested with data on distribution, local density, body size, and feeding habits for a set of 100 Neotropical forest mammals.In a bivariate plot of distributional range against local density, species clustered according to their trophic or taxonomic groups. This indicates that diet and phylogenetic history have an influence on rarity. A negative correlation was found between distribution and abundance. However this correlation was weaker within trophic or taxonomic groups, and vanished when body size was held constant. These results show that both distribution and abundance are valid and independent estimators of rarity when comparing species with similar sizes and ecological traits. Regression analysis showed that larger animals tend to have lower densities and wider distributional ranges. Rarity is clearly associated with body size.A dichotomous classification of rarity based on area of distribution and local density is suitable for Neotropical forest mammals. Species in each of four categories created by such a scheme require different conservation and management policies that are determined by the ecological characteristics of the species. Final conservation strategies must also be shaped by political and economic constraints.
Population Viability Analysis for an Endangered Plant
Authors: MENGES ERIC S. 
Published: April 2005

Abstract:Demographic modeling is used to understand the population viability of Furbish's lousewort,Pedicularis furbishiae, a perennial plant species endemic to the St. John River Valley in northern Maine. Environment‐specific summaries of demographic parameters (survivorship, growth, and fecundity) over four years, organized into stage‐based projection matrices, provide predictions of future population dynamics given a deterministic extension of past conditions. Stochastic modeling, using (I) empirically observed variation in demographic parameters, and (2) estimated rates of natural catastrophes, leads to predictions of extinction probability.P. furbishiaeviability has varied widely over the study period Viable populations with finite rates of increase > 1 are found where cover is low, woody plants do not dominate, and disturbance does not occur. Rates of increase vary over time, suggesting that stochastic analyses would be realistic. Stochastic measures of population viability incorporating environmental variation suggest that early successional environments, especially wetter sites, can support viable populations in the absence of disturbance. However; observed rates of natural catastrophe dominate viability estimates of individual populations. Metapopulation dynamics feature extinction rates that are greater than recolonization rates, and may be affected by land use in the watershed Species management needs to consider a large‐scale view of the riverine corridor.
Biodiversity Loss in the Temperate Zone: Decline of the Native Fish Fauna of California
Authors: MOYLE PETER B. , WILLIAMS JACK E. 
Published: April 2005

AbstractIn proportion to the entire fauna, loss of species may be as great in temperate regions as in tropical regions. To test the validity of this statement we analyzed the status of the native fish fauna of California, using a methodology that quantifies expert knowledge. Of 113 native taxa, 6 percent are extinct, 12 percent are officially listed as threatened or endangered 6 percent deserve immediate listing I7 percent may need listing soon, 22 percent show declining populations but are not yet in serious trouble, and 36 percent appear to be secure. Much of the faunal decline has taken place in recent years; it has included unexpectedly rapid declines of once abundant species. Fish taxa in serious trouble are most likely to be (1) endemic to California, (2) restricted to a small area, (3) occupants of just one drainage basin, (4) part of a fish assemblage of less than five species, and (5) found in isolated springs, warm water streams, or big rivers. Water diversions and introduced species, acting in concert, seem to be the principal causes of the decline of the native fauna, although other types of habitat degradation have contributed as well. The situation in California, with its high degree of endemism (60 percent), may be regarded as extreme but fish faunas in other temperate regions show signs of being nearly as stressed. It is likely that the situation with fish reflects a more general decline of the biota of temperate regions of the world.
Birds in a Farmland—More Species in Small than in Large Habitat Island
Authors: LOMAN JON , VON SCHANTZ TORBJRN 
Published: April 2005

Abstract: Birds were censused on habitat islands to investigate the effect of vegetation, island size, and isolation on the density and species diversity of birds.The density of birds was highest on small habitat islands and in islands close to other islands, especially large ones. We suggest that this is because birds on small habitat islands utilize resources from surrounding fields. After compensating for sampling effect (the fact that we made more observations and there are more territories on large islands), we analyzed the species richness of different islands. We found that there are more territorial species (i.e., bird species whose territories are readily mapped) on small than on large islands. We discuss different causes for this finding. We also found that a given area comprised of many small islands contains more species than the same area comprised of only a few large islands. This is true for both all observed bird species and for all recorded territorial species. We conclude that, when considering conservation from a local perspective, it is important to protect all nonmatrix land in this type of landscape. This will ensure a high local diversity.
Continuous ST‐segment Monitoring of Patients with Right Bundle Branch Block and Suspicion of Acute Myocardial Infarction
Authors: Gunnarsson Gunnar , Eriksson Peter , Dellborg Mikael 
Published: April 2005

Background: Patients with right bundle branch block comprise 5–9% of all patients with acute myocardial infarction. In spite of this, limited data exist on early diagnosis or the usefulness of continuous electrocardiographic monitoring in these patients. Methods: A prospective multicenter study with 14 Swedish coronary care units. Patients with right bundle branch block and suspicion of acute myocardial infarction with less than 6 hours symptom duration were included. All patients were monitored with continuous vectorcardiography for 12–24 hours. Results: Seventy‐nine patients were included, 43% had acute myocardial infarction. Patients with acute myocardial infarction had significantly higher initial ST‐vector magnitude values (P = 0.0014) compared to patients without acute myocardial infarction. Patients with acute myocardial infarction also showed gradual regression of ST‐vector magnitude over time that was not seen for patients without acute myocardial infarction (P = 0.005). ST‐vector magnitude measured at the J‐point differentiated best between patients with and without acute myocardial infarction. A cutoff value of 125 μV for initial ST‐vector magnitude resulted in 55% sensitivity and 87% specificity for the diagnosis of acute myocardial infarction. Over time, patients with acute myocardial infarction showed greater changes in QRS‐vector difference compared to patients without acute myocardial infarction (P = 0.052). Conclusion: Vectorcardiographic monitoring shows good diagnostic abilities for patients with right bundle branch block and clinical suspicion of acute myocardial infarction and could be useful for continuous monitoring of these patients.
Individual QT–R‐R Relationship: Average Stability over Time Does Not Rule Out an Individual Residual Variability: Implication for the Assessment of Drug Effect on the QT Interval
Authors: Extramiana Fabrice , Maison‐Blanche Pierre , Badilini Fabio , Beaufils Philippe , Leenhardt Antoine 
Published: April 2005

Background: Universal QT correction formulae have been shown to under or overcorrect the QT interval duration. Individual QT–R‐R modeling has been proposed as a preferable solution for heart rate correction of QT intervals. However, the QT–R‐R relationship stability over time needs to be evaluated. Methods: The present report is part of randomized, double‐dummy, and placebo‐controlled 4‐way crossover phase 1 study (48 healthy volunteers). Each randomized period included a run‐in placebo day followed the day after by drug administration, with moxifloxacin as a positive control for QT interval measurement. Digital Holter ECG data were analyzed using the “bin” approach. For each period, individual QT–R‐R relationship were calculated using two different models (linear and parabolic log–log models). Results: The mean intrasubject variability for the α coefficient of the linear modeling (SDintra = 0.011 ± 0.005) reached 28.6 ± 10.2%. When the parabolic model was considered, the SDintra was 0.026 ± 0.009 for the α coefficient. The QT–R‐R relationship variability was in part related to long‐term RR changes (R2= 30%, P < 0.05). However, no significant time effect (ANOVA) was evidenced for QT–R‐R coefficients. Moxifloxacin significantly increased the α coefficient of the QT–R‐R relationship from 0.07 ± 0.018 to 0.085 ± 0.019, P < 0.05 (linear model). Conclusions: The individual QT–R‐R relationship shows a residual variability in part related to long‐term autonomic changes. In addition, the QT–R‐R relationship might be modulated by the drug tested. As a consequence, pretherapy QT–R‐R relationship obtained in a given patient cannot be used as a fingerprint throughout a drug trial.
The Value of Magnetocardiography in the Course of Coronary Intervention
Authors: Hailer Birgit , Van Leeuwen Peter , Chaikovsky Illja , Auth‐Eisernitz Sabine , Schäfer Harald , Grönemeyer Dietrich 
Published: April 2005

Background: The noninvasive detection of restenosis after percutaneous coronary intervention (PCI) remains a clinical challenge. Previous studies have shown that magnetocardiograms reveal obvious changes in patients with coronary artery disease (CAD) and normal electrocardiogram (ECG) at rest. Hypothesis: The present study aimed to evaluate the potential of magnetocardiography (MCG) for the detection of electrophysiological changes in the course of successful PCI. Methods: Twelve‐lead ECG and unshielded four‐channel MCG (SQUID AG, Essen, Germany) were registered at nine prethoracic sites in 50 patients with CAD (62 10 years; EF = 76 11%; registration: before, 24 hours, and 1 month (n = 25) after PCI) and 57 normals (51 9 years). Current density vector (CDV) maps were reconstructed within the ST–T interval and classified from category 0 (normal) to category 4 (grossly abnormal). In both groups and at all registration times, the percentage of each category of maps was calculated and compared. Results: Most CDV maps of normals were classified as category 0, 1, or 2 compared to CAD patients before PCI with most maps of category 3 and 4 (P < 0.0005). Twenty‐four hours after PCI, more maps were classified as category 2 (P < 0.05) and less as category 4 (P < 0.005). One month after PCI the MCG results further improved: more maps were classified as category 1 (P < 0.05) and 2 (P < 0.005) and less maps as category 4 (P < 0.0001). The ECG remained unchanged in the course of PCI. Conclusion: Unshielded four‐channel MCG reveals obvious changes in the course of successful PCI on the basis of CDV map reconstruction during repolarization. The method seems to be suitable for the follow‐up of patients after PCI.
Beating the Poisson limit by coupling an occulting mask to wavefront sensing
Authors: Roux Brice Le , Ragazzoni Roberto 
Published: April 2005

Abstract
We show that by coupling an occulting mask to a wavefront sensor one can achieve sensitivities that exceed by a factor of 2 in variance the Poissonian limit in wavefront sensing. Examples of applications are the extension to fainter objects of conventional adaptive optics, and the increase in the sky coverage of natural guide star multiconjugated adaptive optics.
INTERNATIONAL CORPORATE DIFFERENCES: MARKETS OR LAW?
Authors: Easterbrook Frank H. 
Published: April 2005

Current differences in international corporate ownership and governance systems reflect primarily differences in the efficiency of capital markets, not differences in corporate law. Law is an output of this process, not an input. In countries where financial markets are more efficient, there is both less law and greater investor protection.Unlike nations in Asia and most of Europe, the U.S. and the U.K. have large and efficient capital markets, with no restrictions on cross‐border capital flows. It is thus notsurprising that when American and English banks, mutual funds, and insurers are allowed by law to increase the concentration of their holdings, they don't do so. With efficient markets, there is no money to be made by holding undiversified blocks in public corporations. If public markets were inefficient, entrepreneurs would arrange for large blocks of stock (or take companies private), just as they grant powers of control to venture capitalists.The effect of law on corporate governance and ownership is far less pronounced in America than in Europe and Japan. Restrictions on U.S. banks aside, corporate law in the United States is “enabling”–that is, it lets people do largely what they want in organizing, managing, and financing the firm. Corporate law in Europe and Japan is much more “directory.” And there is a straightforward explanation for this difference: When capital markets are efficient, the valuation process works better, which in turn provides investors with stronger assurances of fairness. When markets are less efficient, some substitute must be found–law, perhaps, or the valuation procedures of banks. Thus, banks play larger corporate governance roles in nations with less extensive capital markets–and corporate law, as the European Union's company directives show, is more restrictive. European corporate law is today about as meddlesome and directory as U.S. law in the late 19th century, before U.S. capital markets became efficient.
CORPORATE OWNERSHIP AND CONTROL IN THE U.K., GERMANY, AND FRANCE
Authors: Franks Julian , Mayer Colin 
Published: April 2005

Like its U.S. counterpart, the U.K. corporate ownership and governance system can be characterized as an outsider system with a large number of public corporations, widely dispersed ownership (though with growing concentrations of institutional shareholdings), and well‐developed takeover markets. By contrast, the much smaller number and proportion of publicly traded German and French corporations are governed by insider systems‐‐those in which the founding families, banks, or other companies have controlling interests and in which outside shareholders are not able to exert much control.The different patterns of ownership in the U.K. and in France and Germany give rise to different incentives and corporate control mechanisms. Concentrated ownership would seem to encourage longer‐term relationships between the company and its investors. But, while perhaps better suited to some corporate activities with longer‐term payoffs, concentrated ownership could also lead to costly delays in undertaking necessary corrective action, particularly if the owners receive “private” benefits from owning and running a business. And, although widely dispersed ownership may increase the likelihood that corrective action will be sought prematurely (as outsiders rush to sell their shares in response to a temporary downturn), the presence of well‐diversified public owners may also be more appropriate for riskier ventures requiring large amounts of new capital investment.Thus, concentrated ownership, while having the potential to reduce information costs and to strengthen incentives to maximize value, can also impose costs in two ways: (1) by forcing managers and other insiders to bear excessive company‐specific risks that could be transferred to well‐diversified outsiders; and (2) by allowing insiders to capture private benefits at the expense of outsiders.
UNIVERSAL BANKS ARE NOT THE ANSWER TO AMERICA'S CORPORATE GOVERNANCE “PROBLEM”: A LOOK AT GERMANY, JAPAN, AND THE U.S.
Authors: Macey Jonathan R. , Miller Geoffrey P. 
Published: April 2005

This article objects to a recent tendency of legal and economic scholars to “romanticize” the corporate governance role of German universal banks and Japanese main banks. There are potential conflicts between banks' interests as lenders and as shareholders that are likely to make banks less‐than‐ideal monitors for outside shareholders. Citing evidence that Japanese corporate borrowers pay above‐market interest rates for their bank financing, Macey and Miller interpret the high interest rates as “rents” earned by Japanese banks on their loan portfolios in exchange for (1) insulating incumbent management of borrower firms from hostile takeover and (2) accepting suboptimal returns on their equity holdings.The main problems with the German and Japanese systems stem from their failure to produce well‐developed capital markets. Concentrated and stable shareholdings reduce the order flow in the market, thereby depriving the market of liquidity. And the lack of capital market liquidity– combined with the intense loyalty of the banks towards incumbent management–removes the ability of outside shareholders to make a credible threat of takeover if managerial performance is substandard.The problem with American corporate governance–if indeed there is one–is not that hostile takeovers are bad, but that there are not enough of them due to regulatory restrictions and misguided legal policies. While U.S. law should be amended to give banks and other debtholders more power over borrowers in the case of financial distress, encouraging U.S. banks to become large stockholders is not likely to improve corporate efficiency. Strengthening the “voice” of American equity holders by eliminating restrictions on the market for corporate control would be the most effective step in improving firm performance.