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In the mid-1970s, many U.S. citizens who had not complied with the requirement that they participate in the military of the United States during the Vietnam War faced a dilemma. In the preceding decade, tens of thousands of them had immigrated to Canada—both legally and illegally—to resist compulsory military service. Richard Nixon refused to allow these resisters to return to the United States. His successor, Gerald Ford, allowed expatriates to return if they agreed to do alternative service. Jimmy Carter attempted to resolve the crisis with an amnesty. Canada did not participate in the Vietnam War and refused to extradite American men to the United States for violations of most conscription and military laws. However, in 1973, in the middle of an immigration crisis, Canada forced the hand of many Americans and others who had entered the country clandestinely by giving them only sixty days to reconcile their residency status with the Canadian government or to risk becoming illegal immigrants and to face deportation. The shifting matrix of laws on both sides of the U.S.–Canada border forced American exiles to decide whether to risk having a status that officially satisfied neither country, to accept the terms of the Ford or Carter repatriation plans and reclaim the perquisites of life in the United States, to remain illegal immigrants in Canada, or to acquire Canadian citizenship. Residency in Canada opened the possibility for a different type of citizenship for American men, one less concerned with their potential contribution to the military might of a nation and more tolerant of their freedom of expression, which might include opposition to war.

Although many approaches have been tried in the attempt to reduce the devastating impact of stroke, tissue plasminogen activator for thromboembolic stroke is the only proved, effective acute stroke treatment to date. Vasopressin, an acute-phase reactant, is released after brain injury and is partially responsible for the subsequent inflammatory response via activation of divergent pathways. Recently there has been increasing interest in vasopressin because it is implicated in inflammation, cerebral edema, increased intracerebral pressure, and cerebral ion and neurotransmitter dysfunctions after cerebral ischemia. Additionally, copeptin, a byproduct of vasopressin production, may serve as a promising independent marker of tissue damage and prognosis after stroke, thereby corroborating the role of vasopressin in acute brain injury. Thus, vasopressin antagonists have a potential role in early stroke intervention, an effect thought to be mediated via interactions with aquaporin receptors, specifically aquaporin-4. Despite some ambiguity, vasopressin V1a receptor antagonism has been consistently associated with attenuated secondary brain injury and edema in experimental stroke models. The role of the vasopressin V2 receptor remains unclear, but perhaps it is involved in a positive feedback loop for vasopressin expression. Despite the encouraging initial findings we report here, future research is required to characterize further the utility of vasopressin antagonists in treatment of stroke.

Purpose: Molecular breast imaging (MBI) is a nuclear medicine technology that uses dual-head cadmium zinc telluride (CZT) gamma cameras to image functional uptake of a radiotracer, Tc-99m sestamibi, in the breast. An important factor in adoption of MBI in the screening setting is reduction of the necessary administered dose of Tc-99m sestamibi from the typically used dose of 740 MBq to approximately 148 MBq, such that MBI’s whole-body effective dose is comparable to that of screening mammography. Methods that increase MBI count sensitivity may allow a proportional reduction in the necessary administered dose. Our objective was to evaluate the impact of two count sensitivity improvement methods on image quality by evaluating count sensitivity, spatial resolution, and lesion contrast in phantom simulations. Methods: Two dual-head CZT-based MBI systems were studied: LumaGem and Discovery NM 750b. Two count sensitivity improvement methods were implemented: registered collimators optimized for dedicated breast imaging and widened energy acceptance window optimized for use with CZT. System sensitivity, spatial resolution, and tumor contrast-to-noise ratio (CNR) were measured comparing standard collimation and energy window setting [126–154 keV (+10%, −10%)] with optimal collimation and a wide energy window [110–154 keV (+10%, −21%)]. Results: Compared to the standard collimator designs and energy windows for these two systems, use of registered optimized collimation and wide energy window increased system sensitivity by a factor of 2.8–3.6. Spatial resolution decreased slightly for both systems with new collimation. At 3 cm from the collimator face, LumaGem’s spatial resolution was 4.8 and 5.6 mm with standard and optimized collimation; Discovery NM 750b’s spatial resolution was 4.4 and 4.6 mm with standard and optimized collimation, respectively. For both systems, at tumor depths of 1 and 3 cm, use of optimized collimation and wide energy window significantly improved CNR compared to standard settings for tumors 8.0 and 9.2 mm in diameter. At the closer depth of 1 cm, optimized collimation and wide energy window also significantly improved CNR for 5.9 mm tumors on Discovery NM 750b. Conclusions: Registered optimized collimation and wide energy window yield a substantial gain in count sensitivity and measurable gain in CNR, with some loss in spatial resolution compared to the standard collimator designs and energy windows used on these two systems. At low-count densities calculated to represent doses of 148 MBq, this tradeoff results in adequate count density and lesion contrast for detection of lesions ≥8 mm in the middle of a typical breast (3 cm deep) and lesions ≥6 mm close to the collimator (1 cm deep).

We develop an economic model of “greenwash,” in which a firm strategically discloses environmental information and a non-governmental organization (NGO) may audit and penalize the firm for failing to fully disclose its environmental impacts. We identify conditions under which NGO punishment of greenwash backfires, inducing the firm to become less rather than more forthcoming about its environmental performance. We show that complementarities with NGO auditing may justify public policies encouraging firms to adopt environmental management systems. Mandatory disclosure rules offer the potential for better performance than NGO auditing, but the necessary penalties may be so large as to be politically unpalatable. If so, a mix of mandatory disclosure rules, NGO auditing and environmental management systems may be needed to induce full environmental disclosure.

Environmental “public voluntary programs” (PVPs) involve government offers of positive publicity and technical assistance to firms that reach certain environmental goals. A growing body of empirical work suggests these programs generally have little impact on the behavior of their participants. A natural policy conclusion would be to eliminate PVPs, but we argue that such a conclusion is premature. Many PVPs are best viewed as information diffusion programs, so identifying their effects econometrically is difficult because information is likely to diffuse to nonparticipants. Thus, after the early phases of even a successful PVP, it may well be impossible to detect a difference in the performance between participants and nonparticipants. We argue that new estimation approaches are needed to identify the effects of PVPs. We also explore the design of PVPs in detail, showing how PVPs can potentially enhance the diffusion of cost-effective techniques for pollution abatement.

We study three corporate nonmarket strategies designed to influence the lobbying behavior of other special interest groups: (1) astroturf, in which the firm covertly subsidizes a group with similar views to lobby when it normally would not; (2) the bear hug, in which the firm overtly pays a group to alter its lobbying activities; and (3) self-regulation, in which the firm voluntarily limits the potential social harm from its activities. All three strategies reduce the informativeness of lobbying, and all reduce the payoff of the public decision-maker. We show that the decision-maker would benefit by requiring the public disclosure of funds spent on astroturf lobbying but that the availability of alternative influence strategies limits the impact of such a policy.

In many markets, governments set minimum quality standards while some sellers compete on the basis of quality by exceeding them. Such quality leadership strategies often win public acclaim, especially when they involve environmental attributes. Using a duopoly model of vertical product differentiation, we show that if the high-quality firm can commit to a quality level before regulations are promulgated, it induces the regulator to weaken standards, and welfare falls. Our results raise doubts about the social benefits of corporate self-regulation, and highlight the dangers of lengthy delays between legislative mandates for new regulations and their implementation.

Corporate environmental initiatives have been attributed to a variety of different motives, including cost-cutting, marketing to ‘green’ consumers willing to pay extra for environmentally friendly products, and shaping future government regulation (including the possible preemption of regulation). Understanding what really motivates corporate environmentalism is important for policymakers, since the effectiveness of government environmental policies depends in large part on how corporations will respond to them. We focus on the welfare implications of two alternative strategies firms may use to shape government regulations: (i) attempting to preempt future legislation altogether or (ii) failing this, to soften the impact of new laws by inducing regulators to set relatively weak standards. We show that while the first sounds threatening to social welfare, it produces political cost savings that outweigh any weakening of environmental performance. The second motivation, however, raises corporate profits, but not by enough to outweigh the resulting loss of environmental quality. Copyright © 1999 John Wiley & Sons, Ltd and ERP Environment.

Peripheral primitive neuroectodermal tumors (PNETs) are small, round, blue cell, sarcomatous neoplasms of the bone and soft tissues that arise from neuroectodermal elements and primarily occur in children and adolescents. In adults, they are extremely rare and have been reported in the chest wall (Askin tumor) and other visceral sites. 1-6 To our knowledge, a primary breast PNET has not been reported. 1 We present a case of a primary breast PNET that was initially confused with an epidermal inclusion cyst.

This paper explores problems and issues arising from the application of an objectives framework to the discipline of history in the secondary school context. Specifically the focus is upon a close analysis of the use of skills objectives in history. Analysis of interviews with syllabus writers and document analysis provided the basis from which it is concluded that the New South Wales (NSW) 1986 Two Unit Modern History syllabus is an ambitious curriculum document which created considerable difficulties for teachers intent on using its skills‐based objectives.

Introduction: Stereological evidence for loss of neurons after human blunt head-injury is lacking. A quantitative analysis of total numbers of neurons in two different brain regions in nonhead-injured control (n = 10) and severely head-injured patients (n = 24) (age range 18–64) was undertaken. Material and methods: 8 µm paraffin sections of the left and right thalami and of the left hippocampus from all patients were cut and cresyl violet stained. The neuronal size in subfields of the hippocampus, and dorsomedial, lateral and ventral thalamic nuclei was measured to determine the size of the counting box and, within this, the total number of neurons was counted. Statistical analysis used the Student's t-test. Results: At 1 week, pyramidal neurons were lost from hippocampal subfields CA1 (P = 0.012), CA3 (P = 0.003) and CA4 (P = 0.002), but not from CA2. Further loss occurred at 6 months but only in CA1 (P = 0.033) and CA4 (P = 0.013). No evidence for loss of neurons from any thalamic nucleus was obtained. Conclusions: Loss of neurons from different nuclei of the brain after blunt head-injury occurs both with a different timescale and to a different extent. Anecdotal evidence of damage to thalamic nuclei after head-injury has not been supported using stereology.

Anterograde transport of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) was used to study the normal development of the ipsilateral retinocollicular projection in golden hamsters, and to examine the effect of enucleation of the other eye at birth. In neonatal animals there were retinal fibers and sparsely distributed granular labeling in the superficial layers of the ipsilateral superior colliculus over its entire areal extent. Differences in the uncrossed projections of normal and enucleated animals first became clear at day 5. In normal animals, retinal fibers withdrew from the superficial layers of the superior colliculus, and the projection became concentrated in the stratum opticum, where denser clumps of label in the rostral part of the superior colliculus were first seen at day 5. In enucleated animals, the retinal projection persisted in the most superficial layers, and the density of labeling was higher than in normals. The very sensitive WGA-HRP technique showed retinal fibers extending to the caudal pole of the superior colliculus at all ages: even in normal animals more than 2 weeks of age some fibers reached as far as the inferior colliculus. When the shrunken size of the superior colliculus in the enucleated animals was taken into account, the total areal distribution of the ipsilateral projection was similar in normal animals and enucleates. The major difference between the two groups was in the higher density of ipsilateral labeling, especially in the caudal part of the superior colliculus, and in its more superficial laminar distribution in the enucleated animals.

Using wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) and the fluorescent dyes true blue and nuclear yellow, we have reex-amined the time of arrival at the retina of the centrifugal fibers from the contralateral isthmo-optic nucleus (ION), and have followed, quantitatively, the appearance and fate of other neurons that can be retrogradely labeled from the ipsilateral and contralateral eyes. The earliest age at which ION neurons can be retrogradely labeled is on the ninth day of incubation; the cells labeled at this stage are located in the ventrolateral part of the nucleus on the contralateral side. Over the course of the next 48 hours of development more and more cells can be labeled in a distinct ventrolateral to dorsomedial progression within the nucleus. Since this labeling sequence parallels the time course of generation of the ION neurons it is suggested that the axons of the first ION cells to be generated are the first to reach the contralateral retina, and that in this system there is a close relationship between the time that neurons withdraw from the cell cycle and the time that their axons reach their target area. In addition to the neurons in the ION, about 1,500 cells outside of the nucleus can be retrogradely labeled by WGA-HRP injected into the contra-lateral eye in posthatched chicks. This is slightly less than half the number of “ectopic isthmo-optic neurons” that can be similarly labeled on the 13th day of incubation (when the ION is numerically complete). The reduction in the number of ectopic ION neurons occurs over the same period as the phase of naturally occurring cell death in the ION itself–between the 13th and 17th days of incubation. Long-term labeling experiments with true blue indicate that the disappearance of about 53% of the ectopic ION cells is due to their death rather than the elimination of axon collaterals. In their morphology the ectopic neurons resemble the cells in the ION at early stages in their development, and there is indirect evidence that the ectopic ION neurons which survive also receive an input from the optic tectum through the-tecto-isthmal tract. On these and other grounds it is suggested that the ectopic neurons are indeed “misplaced” ION cells. Between the tenth and 13th days of incubation a small and rather variable number of neurons (58–178) was retrogradely labeled from the ipsilateral eye. Of these neurons with aberrant, ipsilaterally projecting axons, an average of just under 30 lay within the interior of the ION, about 33 were along its borders, and 38 were observed scattered among the ectopic ION cells. Double labeling experiments indicate that early in their development some of these neurons have axon collaterals which project to the contralateral eye. In a large number of animals injected with WGA-HRP after the 17th day of incubation, only a single neuron was seen in the interior of the ipsilateral ION, but, on average, about nine labeled neurons were found along its borders and about 20 were ectopically placed. The numbers of ectopic ION neurons and ION cells with ipsilaterally projecting axons that we have observed are substantially higher than those reported in a previous study (Clarke and Cowan, '76) in which it was also suggested the both classes of cells were effectively eliminated between the 13th and 17th days of incubation. The observed differences are attributable to the greater sensitivity of the WGA-HRP method when used with the chromogen tetramethyl benzidine. It is now clear that although cells in the ION with aberrantly projecting axons (or axon collaterals) may be selected against during the later stages of development, the fate of the ectopic ION neurons is not significantly different from that of the cells in the ION itself, but since they lie outside the nucleus their dendritic processes are not subject to the same morphogenetic influences.

The creativity of 68 middle- and lower-class Caucasian children attending a nursery school, kindergarten, or day-care center was measured by an object-identification originality test. The Mann-Whitney U test was employed to analyze differences, with a confidence level of .05. Firstborn and only children were significantly more creative than later-born children. Middle-class children were significantly more creative than lower-class children. It was concluded that enrollment in a preschool program alone is not sufficient to increase the creativity of lower-class children to the level of their middle-class peers.

Home rule and the short ballot appear to American Observers o be necessary reforms in Russian Municipal government.

Urban land policies in Russia are complicated and their administration is molded to conform to the peculiar organization of the Soviet State. More than one hundred Cities have already worked out definite city plans to be followed by new construction.

This is the third and last of a series of article on the government o Russian cities, the previous articles having appeared in the December adn January issues of the REVIEW

The normal development of the mesencephalic nucleus of the trigeminal nerve has been studied in a series of chicks from the fourth day of incubation until the eighteenth day post-hatching. In addition, the time of origin of the cells in the nucleus has been determined by 3H-thymidine autoradiography, using a variant of the cumulative labeling method. The fully-formed nucleus consists of two distinct groups of unipolar cells, a numerically larger medial division within the tectal commissure and a smaller, lateral division within the stratum griseum periventriculare of the optic tectum. The cells in the lateral group are, on the average, larger than those in the medial part of the nucleus at all stages of development. The entire population of neurons is generated between the third and fourth days of incubation (stages 14 to 24) with the cells in the lateral division being formed slightly earlier (stages 14 to 20) than the medially located cells (stages 16 to 24). When the nucleus is numerically complete, at the eighth or ninth day of incubation, it contains between 4,000 and 4,500 cells. Between days 11 and 13 there is a dramatic loss of cells, especially from the caudal part of the nucleus, to a final population of about 1,100 neurons. This normally occurring cell loss seems to occur at the time muscle spindles are being formed, and appears to be due to the inability of the outgrowing processes of the cells to form appropriate peripheral contacts since it is accentuated by the early extirpation of the mesoderm of the mandibular lobe. These experiments also suggest that in the chick the jaw musculature is, in part, innervated bilaterally by the mesencephalic nucleus.

A first-hand report on municipal developments in Soviet Russia. This month the author describes the changes bought by the revolution. Next month he Will discuss the structure of the new city governments established by the soviets.