13,548 research outputs found
The Hippocampus is Preferentially Associated with Memory for Spatial Context
The existence of a functional-anatomic dissociation for retrieving item versus contextual information within subregions of the medial temporal lobe (MTL) is currently under debate. We used a spatial source memory paradigm during event-related functional magnetic resonance imaging to investigate this issue. At study, abstract shapes were presented to the left or right of fixation. During test, old and new shapes were presented at fixation. Participants responded whether each shape had been previously presented on the “left,” the “right,” or was “new.” Activity associated with contextual memory (i.e., source memory) was isolated by contrasting accurate versus inaccurate memory for spatial location. Item-memory-related activity was isolated by contrasting accurate item recognition without contextual memory with forgotten items. Source memory was associated with activity in the hippocampus and parahippocampal cortex. Although item memory was not associated with unique MTL activity at our original threshold, a region-of-interest (ROI) analysis revealed item-memory-related activity in the perirhinal cortex. Furthermore, a functional-anatomic dissociation within the parietal cortex for retrieving item and contextual information was not found in any of three ROIs. These results support the hypothesis that specific subregions in the MTL are associated with item memory and memory for context
The growth of small corrosion fatigue cracks in alloy 2024
The corrosion fatigue crack growth characteristics of small surface and corner cracks in aluminum alloy 2024 is established. The damaging effect of salt water on the early stages of small crack growth is characterized by crack initiation at constituent particle pits, intergranular microcracking for a less than 100 micrometers, and transgranular small crack growth for a micrometer. In aqueous 1 percent NaCl and at a constant anodic potential of -700 mV(sub SCE), small cracks exhibit a factor of three increase in fatigue crack growth rates compared to laboratory air. Small cracks exhibit accelerated corrosion fatigue crack growth rates at low levels of delta-K (less than 1 MPa square root of m) below long crack delta-K (sub th). When exposed to Paris regime levels of crack tip stress intensity, small corrosion fatigue cracks exhibit growth rates similar to that observed for long cracks. Results suggest that crack closure effects influence the corrosion fatigue crack growth rates of small cracks (a less than or equal to 100 micrometers). This is evidenced by similar small and long crack growth behavior at various levels of R. Contrary to the corrosion fatigue characteristics of small cracks in high strength steels, no pronounced chemical crack length effect is observed for Al by 2024 exposed to salt water
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Anolis bahorucoensis
Number of Pages: 3Integrative BiologyGeological Science
Gestational diabetes mellitus- right person, right treatment, right time?
Background: Personalised treatment that is uniquely tailored to an individual’s phenotype has become a key goal of clinical and pharmaceutical development across many, particularly chronic, diseases. For type 2 diabetes, the importance of the underlying clinical heterogeneity of the condition is emphasised and a range of treatments are now available, with personalised approaches being developed. While a close connection between risk factors for type 2 diabetes and gestational diabetes has long been acknowledged, stratification of screening, treatment and obstetric intervention remains in its infancy.
Conclusions: Although there have been major advances in our understanding of glucose tolerance in pregnancy and of the benefits of treatment of gestational diabetes, we argue that far more vigorous approaches are needed to enable development of companion diagnostics, and to ensure the efficacious and safe use of novel therapeutic agents and strategies to improve outcomes in this common condition
Parents as Fiduciaries
Traditionally, the law has deferred to the rights of biological parents in regulating the parent-child relationship. More recently, as the emphasis of legal regulation has shifted to protecting children\u27s interests, critics have targeted the traditional focus on parents\u27 rights as impeding the goal of promoting children\u27s welfare. Some contemporary scholars argue instead for a child-centered perspective, in contrast to the current regime under which biological parents continue to have important legal interests in their relationship with their children. The underlying assumption of this claim is that the rights of parents and the interests of children often are conflicting, and that greater recognition of one interest means diminished importance to the other.
One way of thinking about a legal regime that seeks to harmonize this conflict is to imagine that the parent\u27s legal relationship to the child is shaped by fiduciary responsibilities toward the child rather than by inherent rights derived from status. Fiduciaries in law are agents who occupy a position of special confidence, superiority, or influence, and thus are subject to strict and non-negotiable duties of loyalty and reasonable diligence in acting on behalf of their principals. Characterizing parents as fiduciaries suggests that the parent-child relationship shares important features with other legal relationships that have been similarly defined, such as trustees and trust beneficiaries, corporate directors and shareholders, executors and legatees, and guardians and wards. Basic structural similarities are apparent. There are information asymmetries in this family relationship that are analogous to those of other fiduciary relationships. Moreover, satisfactory performance by parents, like that of other fiduciaries, requires considerable discretion, and children, like other principals, are not in a position to direct or control that performance. Here, as in other contexts, the challenge for legal regulation is to encourage the parent to act so as to serve the interests of the child rather than her own conflicting interests, and yet to do so in a context in which monitoring parental behavior is difficult
From Contract to Status: Collaboration and the Evolution of Novel Family Relationships
The past decade has witnessed a dramatic change in public attitudes and legal status for same-sex couples who wish to marry. These events demonstrate that the legal conception of the family is no longer limited to traditional marriage. They also raise the possibility that other relationships – cohabiting couples and their children, voluntary kin groups, multigenerational groups and polygamists – might gain legal recognition as families. This Article probes the challenges faced by aspiring families and the means by which they could attain their goal. It builds on the premise that the state remains committed to social welfare criteria for granting family status, recognizing as families only those categories of relationships that embody a long-term commitment to mutual care and interdependence, and, on that basis, function well to satisfy members’ dependency needs. Groups aspiring to legal recognition as families must overcome substantial uncertainties as to whether they meet these criteria if they are to obtain the rights and obligations of legally recognized families. Uncertainty contributes to a lack of confidence in the durability and effectiveness of novel relationships on the part of the aspiring family members themselves, the larger social community and, ultimately, the state. We develop an informal model to illustrate the nature of these uncertainties, as well as the solutions to the possible obstacles they create. Using a hypothetical group consisting of two adult men and two adult women in a polyamorous relationship, we show how legal family status for novel groups can result from an evolutionary process for overcoming uncertainties that uses collaborative techniques to build trust and confidence. Collaborative processes have been shown in other settings to be effective mechanisms for creating trust incrementally and thus appear to offer a way forward in the evolution of other novel families. We show that the successful movement to achieve marriage rights for LBGT couples has roughly conformed to the collaborative processes we propose, and the absence of meaningful collaboration is one factor explaining the stasis that characterizes the status of unmarried cohabitants. This evidence supports the prediction that the future progress of other aspiring family groups toward attaining legal status may depend on how well they are able to engage the collaborative mechanisms that smooth the path from contract to status
Volumetric microvascular imaging of human retina using optical coherence tomography with a novel motion contrast technique
Phase variance-based motion contrast imaging is demonstrated using a spectral domain optical coherence tomography system for the in vivo human retina. This contrast technique spatially identifies locations of motion within the retina primarily associated with vasculature. Histogram-based noise analysis of the motion contrast images was used to reduce the motion noise created by transverse eye motion. En face summation images created from the 3D motion contrast data are presented with segmentation of selected retinal layers to provide non-invasive vascular visualization comparable to currently used invasive angiographic imaging. This motion contrast technique has demonstrated the ability to visualize resolution-limited vasculature independent of vessel orientation and flow velocity
The Case Against Equity in American Contract Law
The American common law of contracts appears to direct courts to decide contract disputes by considering two opposing points of view: the ex ante perspective of the parties’ intent at the time of formation, and the ex post perspective of justice and fairness to the parties at the time of adjudication. Despite the black letter authority for both perspectives, the ex post perspective cannot withstand scrutiny. Contract doctrines taking the ex post perspective – such as the penalty, just compensation, and forfeiture doctrines – were created by equity in the early common law to police against abuses of the then prevalent penal bond. However, when the industrial revolution pushed courts to accommodate fully executory agreements, and parties abandoned the use of penal bonds, the exclusively ex ante focus of the new contract law that emerged rendered the ex post doctrines obsolete. While initially intended to do justice between the parties, if used today these doctrines perversely and unjustly deny parties contractual rights that were bargained for in a free and fair agreement. Yet judges continue to recognize the ex post doctrines, even as they struggle to reconcile them with respect for the parties’ intent. Although infrequently applied, the ex post doctrines are far from dead letter. The penumbra of uncertainty they cast over contract adjudication continues to undermine contracting parties’ personal sovereignty. The only case for continuing to recognize these equitable interventions, therefore, must turn on whether they serve a new valid purpose. We consider and reject the possible purposes of paternalism and anti-opportunism suggested by contemporary pluralist scholars. In our view, the criteria governing theories of legal interpretation support the interpretation of contract law as exclusively serving personal sovereignty rather than any pluralist interpretation. Under its best interpretation, contract law has no place for the ex post perspective
Government Royalties on Sales of Pharmaceutical and Other Biomedical Products Developed with Substantial Public Funding: Illustrated with the Technology Transfer of the Drug-Eluting Coronary Stent
This study develops a detailed description of the successful technology transfer of an invention—the drug-eluting coronary stent—originating in intramural research within the National Institutes of Health. The history of the commercialization of the invention is used to illustrate a new policy, proposed and explained in this study, for the payment to the government of royalties on the sales of biomedical products developed with substantial public funding provided through indirect as well as direct funding avenues. The proposed policy addresses concerns about the high prices that taxpayers as consumers pay for biomedical products that were developed with funding from the taxpayers as investors. The study explains the theoretical circumstances in which the policy would not adversely affect the appropriate level of R&D investment, and then uses the history of the drug-eluting coronary stent as an example where biomedical R&D is consistent with those circumstances
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