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Extraordinary Increase (extraordinary + increase)
Selected AbstractsGenetic damage detected in CD-1 mouse pups exposed perinatally to 3,-azido-3,-deoxythymidine and dideoxyinosine via maternal dosing, nursing, and direct gavageENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 1 2004Jack B. Bishop Abstract Human immunodeficiency virus (HIV)-infected pregnant women are administered nucleoside-analogue antiretrovirals to reduce maternal-infant viral transmission. The current protocol recommends treating newborns for 6 additional weeks postpartum. The treatment is effective, but the risk of drug-induced chromosomal damage in neonates remains undefined. We used a mouse model to investigate this concern. In a multigeneration reproductive toxicity study, female CD-1 mice received 3,-azido-3,-deoxythymidine (AZT) and dideoxyinosine (ddI) (50/250, 75/375, 150/750 mg/kg/day AZT/ddI) by gavage twice daily in equal fractions beginning prior to mating and continuing throughout gestation and lactation. Direct pup dosing (same regimen) began on postnatal day (PND) 4. Peripheral blood erythrocytes of male pups were screened for micronuclei, markers of chromosomal damage, on PNDs 1, 4, 8, and 21. Extraordinary increases in micronucleated cells were noted in pups for each treatment group at each sampling time; treated dams exhibited smaller yet significant increases in micronucleated erythrocytes. The frequencies of micronucleated cells in untreated pups were higher than in the untreated dams, and all pups had markedly elevated levels of circulating reticulocytes compared to dams. These observations suggest that fetal and neonatal mouse hematopoietic precursor cells have heightened sensitivity to genotoxic agents, perhaps due to rapid cell proliferation during the perinatal period of development. The amount of genetic damage observed in treated pups raises concern for the potential of similar damage in humans. Investigations of chromosomal integrity in exposed newborns and children are recommended. Environ. Mol. Mutagen. 43:3,9, 2004. © 2004 Wiley-Liss, Inc. [source] FREE CASH FLOW AND PUBLIC GOVERNANCE: THE CASE OF ALASKAJOURNAL OF APPLIED CORPORATE FINANCE, Issue 3 2000Dwight R. Lee In a widely cited 1986 article in the American Economic Review, Michael Jensen gave the concept of free cash flow (FCF) a new twist by redefining it as cash flow in excess of that required to fund all projects with positive net present values. Put another way, FCF represents funds available in the firm that managers may choose to hold as idle cash, return to shareholders, or invest in projects with returns below the firm's cost of capital. In redefining FCF in this way, Jensen converted FCF from a measure of economic income and value into a measure of corporate assets available for discretionary, and potentially value-destroying, use by firm managers. And, as he argued in his important article, managers in mature businesses with substantial free cash flow have a tendency to destroy value by plowing too much capital back into those businesses or, often worse, making ill-advised acquisitions in unrelated businesses. Several methods have been developed in financial markets and internal corporate governance systems to discourage managers from wasting FCF. Better monitoring by boards of directors, large ownership blocks, and properly aligned management compensation contracts are all parts of the solution. And the extraordinary increase in stock repurchases in recent years, invariably applauded by investors, is another illustration of the market's success in encouraging companies to address their free cash flow problems. But if the "FCF problem" of the private sector has attracted considerable attention from finance scholars, the problem is even more acute in the public sector, where FCF can be thought of as tax revenue in excess of what is required to finance well-defined and generally accepted levels of public services. Unlike the private sector, in the public sector there are neither measures nor mechanisms by which to monitor and constrain wasteful spending by elected officials. In this article, the authors attempt to measure the costs to taxpayers of government FCF using the case of Alaska, which since 1969 has received a huge windfall of tax revenue from North Slope oil leases. After examining the state's public finances from 1968 through 1993, the authors offer $25 billion as a conservative estimate of the social losses from Alaska's waste of free cash flow during that 25-year period. [source] Sexual selection research on spiders: progress and biasesBIOLOGICAL REVIEWS, Issue 3 2005Bernhard A. Huber ABSTRACT The renaissance of interest in sexual selection during the last decades has fuelled an extraordinary increase of scientific papers on the subject in spiders. Research has focused both on the process of sexual selection itself, for example on the signals and various modalities involved, and on the patterns, that is the outcome of mate choice and competition depending on certain parameters. Sexual selection has most clearly been demonstrated in cases involving visual and acoustical signals but most spiders are myopic and mute, relying rather on vibrations, chemical and tactile stimuli. This review argues that research has been biased towards modalities that are relatively easily accessible to the human observer. Circumstantial and comparative evidence indicates that sexual selection working via substrate-borne vibrations and tactile as well as chemical stimuli may be common and widespread in spiders. Pattern-oriented research has focused on several phenomena for which spiders offer excellent model objects, like sexual size dimorphism, nuptial feeding, sexual cannibalism, and sperm competition. The accumulating evidence argues for a highly complex set of explanations for seemingly uniform patterns like size dimorphism and sexual cannibalism. Sexual selection appears involved as well as natural selection and mechanisms that are adaptive in other contexts only. Sperm competition has resulted in a plethora of morphological and behavioural adaptations, and simplistic models like those linking reproductive morphology with behaviour and sperm priority patterns in a straightforward way are being replaced by complex models involving an array of parameters. Male mating costs are increasingly being documented in spiders, and sexual selection by male mate choice is discussed as a potential result. Research on sexual selection in spiders has come a long way since Darwin, whose spider examples are reanalysed in the context of contemporary knowledge, but the same biases and methodological constraints have persisted almost unchanged through the current boom of research. [source] Enhancement of Methanol Tolerance in DMFC Cathode: Addition of Chloride IonsCHEMPHYSCHEM, Issue 10 2008Sunghyun Uhm Dr. Abstract In the operation of a direct methanol fuel cell, the modification by chloride ions on the surface of a Pt cathode can facilitate the extraordinary increase of power performance and long-term stability. Analyzing the results of cyclic voltammograms and electrochemical impedance spectroscopy, the positive shift of Pt oxidation onset potential and the depression of oxidation current are observed, which results from the role of chloride as surface inhibitor. In addition, O2 temperature-programmed desorption and X-ray photoelectron spectroscopy also reveal that the suppression of Pt surface oxide can be best understood in terms of lower binding of oxygen species by the alteration of electronic state of Pt atoms. Such a reduced surface oxide formation not only provides more efficient proton adsorption sites with high selectivity but also decreases the mixed potential by crossover methanol, resulting in higher performance and stability even under high voltage long-term operation. [source] Late Marriage and Less Marriage in JapanPOPULATION AND DEVELOPMENT REVIEW, Issue 1 2001Robert D. Retherford Between 1975 and 1995, the singulate mean age at marriage in Japan increased from 24.5 to 27.7 years for women and from 27.6 to 30.7 years for men, making Japan one of the latest-marrying populations in the world. Over the same period, the proportion of women who will never marry, calculated from age-specific first-marriage probabilities pertaining to a particular calendar year, increased from 5 to 15 percent for women and from 6 to 22 percent for men,behaviors sharply different from those characterizing the universal-marriage society of earlier years. This article investigates how and why these changes have come about. The reasons are bound up with rapid educational gains by women, massive increases in the proportion of women who work for pay outside the home, major changes in the structure and functioning of the marriage market, extraordinary increases in the prevalence of premarital sex, and far-reaching changes in values relating to marriage and family life. [source] | ||||||||||