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This article describes the benefits of using municipal investment contracts for the reinvestment of municipal bond proceeds. It shows how municipal investment contracts may be structured to meet a borrower's objectives of liquidity, security, and maximization of investment yield. Several examples show how a custom-tailored municipal investment contract may achieve results unobtainable through traditional investment vehicles.
This paper argues that investing in children's health is a sound economic decision for governments to take, even if the moral justifications for such programmes are not considered. The paper also outlines dimensions that are often neglected when public investment decisions are taken. The conclusion that can be drawn from the literature studying the relationship between children's health and the economy is that children's health is a potentially valuable economic investment. The literature shows that making greater investments in children's health results in better educated and more productive adults, sets in motion favourable demographic changes, and shows that safeguarding health during childhood is more important than at any other age because poor health during children's early years is likely to permanently impair them over the course of their life. In addition, the literature confirms that more attention should be paid to poor health as a mechanism for the intergenerational transmission of poverty. Children born into poor families have poorer health as children, receive lower investments in human capital, and have poorer health as adults. As a result, they will earn lower wages as adults, which will affect the next generation of children who will thus be born into poorer families.
Cobalt alloy samples were bioactivated during investment casting. The cavities of the investment mold were previously coated with wollastonite. Additionally, before coating with wollastonite, some mold cavities were filled out with graphite rods to avoid a chemical reaction between the wollastonite powder and the investment material. Half of the cast samples were heat treated at 1220 degrees C for 1 h. To perform the in vitro bioactivity assessment, the cast and heat-treated samples were immersed in a simulated body fluid solution (SBF) for a period of 21 days. The surface of the samples before and after immersion in SBF was characterized by SEM, EDX, and XRD analyses. During the casting, particles of pseudowollastonite were embedded on the metallic surface. After immersion of the samples in SBF, a ceramic layer was formed on both the alloy obtained by using the investment mold and the alloy obtained by using the graphite-filled cavity. The ceramic layer was thicker on the alloy cast in the investment mold. The layer was identified as hydroxyapatite by XRD analysis, in all the cases. The heat-treated samples after immersion in SBF showed the formation of a thin homogeneous layer consisting of fine grains of apatite.
Extra-pair paternity is common in many socially monogamous passerine birds with biparental care. Thus, males often invest in offspring to which they are not related. Models of optimal parental investment predict that, under certain assumptions, males should lower their investment in response to reduced certainty of paternity. We attempted to reduce certainty of paternity experimentally in two species, the eastern bluebird, Sialia sialis, and the tree swallow, Tachycineta bicolor, by temporarily removing fertile females on two mornings during egg laying. In both species, experimental males usually attempted to copulate with the female immediately after her reappearance, suggesting that they experienced the absence of their mate as a threat to their paternity. Experimental males copulated at a significantly higher rate than control males. However, contrary to the prediction of the model, experimental males did not invest less than control males in their offspring. There was no difference between experimental and control nests in the proportion of male feeds, male and female feeding rates, nestling growth and nestling condition and size at age 14 days. We argue that females might have restored the males' confidence in paternity after the experiment by soliciting or accepting copulations. Alternatively, males may not reduce their effort, because the fitness costs to their own offspring may outweigh the benefits for the males, at least in populations where females cannot fully compensate for reduced male investment. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.
Males play a variable parental role in reproduction, ranging from no male parental care to extensive male care. Females may acquire either direct or indirect fitness benefits from their mate choice, and direct fitness benefits include male parental care. Theoreticians have traditionally emphasized direct fitness benefits to females in species with extensive male parental care. We review the literature and show extensive variation in the patterns of male care, related to the attractiveness of males to females. At one extreme of this continuum, females invest differentially in parental care, investing more when paired with attractive males. The costs of female parental care and other aspects of parental investment may be balanced by benefits in terms of more attractive sons and/or more viable offspring. At the other extreme, in species with extensive direct fitness benefits, males with preferred sexual phenotypes provide the largest relative share of parental care. A comparative study of birds revealed that the extent of the differential female parental investment was directly related to the frequency of extra-pair paternity. Since extra-pair paternity may arise mainly as a consequence of female choice for indirect fitness benefits, this result supports our prediction that differential parental investment is prevalent in species where females benefit indirectly from their mate choice. The consequences for sexual selection theory of these patterns of male care in relation to male attractiveness are emphasized. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.
Inducible defences have long been considered as a polyphenism opposing defended and undefended morphs. However, in nature, preys are exposed to various levels of predation risk and scale their investment in defence to actual predation risk. Still, among the traits that are involved in the defence, some are specific to one predator type while others act as a more generalised defence. The existence of defence costs could prevent an individual investing in all these traits simultaneously. In this study, we investigate the impact of an increasing level of predator density (stickleback, Gasterosteus aculeatus) on the expression of morphological inducible defences in tadpoles of Rana dalmatina. In this species, investment in tail length and tail muscle is a stickleback-specific response while increased tail fin depth is a more general defence. As expected, we found a relationship between investment in defence and level of risk through the responses of tail fin depth and tail length. We also found an exponential increase of defence cost, notably expressed by convex decrease of growth and developmental rates. We found a relative independence of investment in the different traits that compose the defence, revealing a high potential for fine tuning the expression of defended phenotypes with respect to local ecological conditions.
In Central Europe, Fagus sylvatica and Picea abies represent contrasting extremes in foliage type, crown structure and length of growing season. In order to examine the competitive strategies of these two co-occurring species, we tested the following hypotheses: (1) the space occupied by the foliage of sun branches is characterized by greater foliar mass investment compared to shade branches, (2) the carbon (C) gain per unit of occupied space is greater in sun than in shade branches, and (3) annual C and water costs of the foliage for sustaining the occupied space are low, wherever C gain per unit of occupied space is low. These were investigated in a mature forest in Southern Germany. The examination was based on the annual assessment of space-related resource investments and gains of the foliage. The foliated space around branches was regarded as the relevant volume with respect to aboveground resource availability. Occupied crown space per standing foliage mass was higher in shade compared to sun branches of beech, whereas no difference existed in crown volume per foliage mass between sun and shade branches of spruce (hypothesis 1 accepted for beech but rejected for spruce). However, beech occupied more space per foliage mass than spruce. The C gain per occupied crown volume was greater in sun than in shade branches (hypothesis 2 accepted) but did not differ between species. The amount of occupied space per respiratory and transpiratory costs did not differ between species or between sun and shade branches. In beech and spruce, the proportion of foliage investment in the annual C balance of sun and shade branches remained rather stable, whereas respiratory costs distinctly increased in shade foliage. Hence, shade branches were costly structures to occupy space, achieving only low and even negative C balances (rejection of hypothesis 3), which conflicts with the claimed C autonomy of branches. Our findings suggest that competitiveness is determined by the standing foliage mass and the annual branch volume increment rather than annual investments in foliage. Expressing competitiveness in terms of space-related resource investments versus returns, as demonstrated here, has the potential of promoting mechanistic understanding of plant-plant interactions.
An organism's investment in different traits to reduce predation is determined by the fitness benefit of the defense relative to the fitness costs associated with the allocation of time and resources to the defense. Inherent tradeoffs in time and resource allocation should result in differential investment in defense along a resource gradient, but competing models predict different patterns of investment. There are currently insufficient empirical data on changes in investment in defensive traits or their costs along resource gradients to differentiate between the competing allocation models. In this study, I exposed tadpoles to caged predators along a resource gradient in order to estimate investment in defense and costs of defense by assessing predator-induced plasticity. Induced defenses included increased tail depth, reduced feeding, and reduced swimming activity; costs associated with these defenses were reduced developmental rate, reduced growth, and reduced survival. At low resource availability, these costs predominately resulted in reduced survival, while at high resource availability the costs yielded a reduced developmental rate. Defensive traits responded strongly to predation risk, but did not respond to resource availability (with the exception of feeding activity), whereas traits construed as costs of defenses showed the opposite pattern. Therefore, defensive traits were highly sensitive to predation risk, while traits construed as costs of defense were highly sensitive to resource allocation tradeoffs. This difference in sensitivity between the two groups of traits may explain why the correlation between the expression of defensive traits and the expression of the associated defense costs was weak. Furthermore, my results indicate that genetic linkages and mechanistic integration of multiple defensive traits and their associated costs may constrain time and resource allocation in ways that are not addressed in existing models.
Responding effectively and efficiently to the needs of persons with mental illness returning to the community from prison requires identifying their differences in need and placement difficulties upon return and targeting reintegration investments to reflect these differences. This paper has three parts. The first part profiles the male special needs population in New Jersey prisons. These profiles describe behavioral health and criminal justice characteristics of 2715 male inmates with mental health problems, and are used to identify the scope and nature of the public's investment opportunity. The next part describes the costs associated with possible "investments." The special needs population is classified by need and placement difficulty, and then matched to reentry and community-based treatment programs. Costs are estimated for reentry planning and community-based treatment for the first year post-release. The third part recommends an investment strategy and a set of operational changes that might minimize the loss and maximize the return on the public's investment dollar in mental health.
This study examined the relationship of type of sexually instigating situation (partner behavior conveying emotional investment or not), relationship stage, and gender to self-reported likelihood of engaging in sexual behavior. Participants (200 female and 122 male college students) read scenarios describing partner behavior in eight hypothetical sexual situations. Five of the sexual situations were proposed to explicitly communicate a sense of emotional investment in the relationship, and three other scenarios were conceived as not explicitly conveying emotional investment. Emotional investment situations were hypothesized to influence likelihood ratings as a function of imagined relationship stage (dating or in a serious relationship), manipulated across participants. Situations not conveying investment were hypothesized to influence ratings as a function of both relationship stage and gender. In large part, hypotheses were confirmed. The few exceptions were consistent with other gender-role considerations related to trust and power.
Sex differences in aspects of mental health are examined as a function of uneven parental investment in children. Relative vulnerability is a new construct mediating the influence of parental investment on mental health. Couples (129) in three stages of the family life cycle are measured by scales for parental investment, relative vulnerability, anxiety, depression, and ten psychosomatic syndromes. Results show a path of positive correlations from the parent's sex to level of parental investment, to level of relative vulnerability, and to levels of anxiety and depression. Women invest more than men, and hence they are more vulnerable, anxious, and depressed. They reach the summit of their vulnerability while they have three young children. Relative vulnerability was found to have positive effects along with the negative ones and to affect women in different ways than it does men. Results are interpreted in terms of different parental strategies selected by evolution for each sex.
Individuals of different quality may have different investment strategies, shaping responses to experimental manipulations, thereby rendering the detection of such patterns difficult. However, previous clutch-size manipulation studies have infrequently incorporated individual differences in quality. To examine costs of incubation and reproductive investment in relation to changes in clutch size, we enlarged and reduced natural clutch sizes of four and five eggs by one egg early in the incubation period in female common eiders (Somateria mollissima), a sea duck with an anorectic incubation period. Females that had produced four eggs (lower quality) responded to clutch reductions by deserting the nest more frequently but did not increase incubation effort in response to clutch enlargement, at the cost of reduced hatch success of eggs. Among birds with an original clutch size of five (higher quality), reducing and enlarging clutch size reduced and increased relative body mass loss respectively without affecting hatch success. In common eiders many females abandon their own ducklings to the care of other females. Enlarging five-egg clutches led to increased brood care rate despite the higher effort spent incubating these clutches, indicating that the higher fitness value of a large brood is increasing adult brood investment. This study shows that the ability to respond to clutch-size manipulations depends on original clutch size, reflecting differences in female quality. Females of low quality were reluctant to increase investment at the cost of lower hatch success, whereas females of higher quality apparently have a larger capacity both to increase incubation effort and brood care investment.
Conflict between mates over the amount of parental investment by each partner is probably the rule except in rare cases of genetic monogamy. In systems with parental care, males may frequently benefit by providing smaller investments than are optimal for individual female partners. Females are therefore expected to choose males that will provide the largest amounts of parental investment. In some species, however, the preferred males provide less care than their rivals. Focusing on species in which males invest by feeding their mates, I use a simple model to demonstrate the conditions under which males preferred by females may have optimal donations that are smaller than those of less-preferred rivals. Pre-mating female choice may sufficiently bias the perception of mate availability of preferred males relative to their rivals such that preferred males gain by conserving resources for future matings. Similarly, 'cryptic' biases in favour of high-quality ejaculates by females can compensate for smaller than average donations received from preferred males. However, post-fertilization cryptic choice should not change the optimal donations of preferred males relative to their rivals. I discuss the implications of this work for understanding sexual selection in courtship-feeding animals, and the relevance of these systems to understanding patterns of investment for animals in general.
OBJECTIVES: To evaluate a dynamic form of weighted vest exercise suitable for home use and designed to enhance muscle power, balance, and mobility. DESIGN: A single-blind, randomized, controlled trial. SETTING: Outpatient exercise research facility situated within an academic long-term care center. PARTICIPANTS: Twenty-one community-dwelling women aged 70 and older with a Short Physical Performance Battery (SPPB) score between 4 and 10 (out of 12). INTERVENTIONS: Subjects were randomized into a progressive resistance-training program using weighted vests for resistance with exercises designed to be specific to mobility tasks and have a component performed at the fastest possible velocity (Increased Velocity Exercise Specific to Task (InVEST), n=11) or a control exercise group (control, n=10), which performed slow-velocity, low-resistance exercise. Both groups exercised three times a week for 12 weeks. MEASUREMENTS: Changes in muscle power, balance, and physical performance were compared. RESULTS: In comparison to control group, InVEST group manifested significant improvements (P<.05) in leg power across measurements obtained at 75% to 90% of the one-repetition maximum. Both groups demonstrated significant improvements in chair stand and SPPB score from baseline, and the InVEST group showed significant improvements in gait speed and chair stand from baseline (P<.05). InVEST produced significantly greater changes in chair stand time than control (P<.05). CONCLUSION: InVEST training appears be an effective means of enhancing leg power and chair rise in this population and is worthy of further investigation as a means of enhancing balance and mobility.
To determine the relevant psychosexual characteristics of invested partners of patients with sexual disorders, the authors administered the Derogatis Sexual Functioning Inventory (DSFI) to 51 invested partners and 200 normal volunteers. Female invested partners (N = 18) participated in a significantly more constricted range of specific sexual activities and revealed significantly lower sexual drive than the normal women. Tbey also had significantly lower scores on the femininity component of the gender role definition subtest. Male invested partners (N = 33) also showed significantly lower femininity scores and had somewhat lower scores on endorsement of specific sexual experiences. Degree of sexual satisfaction in the invested partners was comparable to that of their sexually dysfunctional partners.
Reinforcement process may underlie decisions frequently found in organizations to escalate investments of time, money and other resources in strategies (e.g., product development, capital investment, plant expansion) that do not result in immediate reinforces. Whereas cognitive biases have been proffered in previous explanations, the present analysis suggested that this persistence is a form of resistance to extinction arising from experiences with past investments that were variably reinforced. This explanation was examined in two experiments by varying the pattern of returns and losses subjects experienced for investment decisions prior to experiencing a series losses. Consistent with the proposed explanation, two conditions resulted in higher levels of recommitment during continuous losses: (a) training using a variable schedule of partial reinforcement, and (b) no training on the task. Results indicate that behavior analysis can be used to understand and control situations in organizations that are prone to escalation, such as investments in the research and development of new product lines and extensions of further loans to customers.
Forest environmental conditions are affected by climate change, but investments in forest environmental quality can be used as part of the climate change mitigation strategy. A key question involving the potential use of forests to store more carbon as part of climate change mitigation is the impact of forest investments on the timing and quantity of forest volumes that affect carbon storage. Using an economic optimization model, we project levels of U.S. forest volumes as indicators of carbon storage for a wide range of private forest investment scenarios. Results show that economic opportunities exist to further intensify timber management on some hectares and reduce the average timber rotation length such that the national volume of standing timber stocks could be reduced relative to projections reflecting historical trends. The national amount of timber volume is projected to increase over the next 50 yr, but then is projected to decline if private owners follow an economic optimization path, such as with more forest type conversions and shorter timber rotations. With perfect foresight, future forest investments can affect current timber harvest levels, with intertemporal linkages based on adjustments through markets. Forest investments that boost regenerated timber yields per hectare would act to enhance ecosystem services (e.g., forest carbon storage) if they are related to the rate of growth and extent of growing stock inventory.
The primary goal of this research was to investigate the possibility that being very invested in goals has psychological trade-offs. Self-report methods were used in a concurrent study with college students (Study 1) and a longitudinal study with elementary school children (Study 2). The results of both studies provided support for the hypothesis that high goal investment has psychological trade-offs. Such investment was associated with positive emotions as well as with worrying, both concurrently and longitudinally. In addition, evidence for mediational mechanisms was provided: Perceptions of accomplishment accounted for the relation between goal investment and positive emotions; the link between goal investment and worrying was mediated by predictions that failure would be upsetting. The implications of these findings for distinguishing between depressive and anxiety symptoms are discussed.