699 research outputs found
Cancer: The Great Challenge for Immunology
The existence of immunity to cancer was postulated by the eminent scientists who helped to establish the discipline of immunology. In 1907 Clowes suggested that human resistance to cancer resulted from what we today call “immune surveillance.” During the ensuing 70 years the results obtained from experimental animal cancers and human cancers have greatly influenced the palatability of tumor-immunity theories. Early optimism that immunity to cancer could be specifically induced waned and almost disappeared when it was demonstrated that the rejection of cancer transplants resulted from transplantation immunity and not tumor immunity. A sustained wave of enthusiasm for immunity to cancer appeared after demonstrations that inbred animals could be immunized to cancers arising in the inbred strain
Some Projects in Automatic Programming
Work reported herein was conducted at the Artificial Intelligence Laboratory, a Massachusetts Institute of Technology research program supported in part by the Advanced Research Projects Agency of the Department of Defense and monitored by the Office of Naval Research under Contract Number N00014-70-A-0362-0005.This paper proposes three research topics within the general framework of Automatic Programming. The projects are designing (1) a student programmer, (2) a robot programmer and (3) a physicist's helper. The purpose of these projects is both to explore fundamental ideas regarding the nature of programming as well as to propose practical applications of AI research. The reason for offering this discussion as a Working Paper is to suggest possible research topics which members of the laboratory may be interested in pursuing.MIT Artificial Intelligence Laborator
Executive Compensation in Municipalities
[Excerpt] In this paper we are concerned with the salaries of three important municipal officials; city-managers, police chiefs, and fire chiefs. We present a model that relates the salaries of these officials to a set of explanatory variables, the most important being measures associated with job performance. Two of these measures of performance are developed in the study. Further, the influence of the city-manager form of government on the incentive structure facing police chiefs and fire chiefs, and the interdependence betwen the salaries of police chiefs and fire chiefs is investigated. The model is tested using cross-section data for 1967
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Dead Sea drawdown and monsoonal impacts in the Levant during the last interglacial
Sediment cores recovered by the Dead Sea Deep Drilling Project (DSDDP) from the deepest basin of the hypersaline, terminal Dead Sea (lake floor at ∼725 m below mean sea level) reveal the detailed climate history of the lake's watershed during the last interglacial period (Marine Isotope Stage 5; MIS5). The results document both a more intense aridity during MIS5 than during the Holocene, and the moderating impacts derived from the intense MIS5e African Monsoon. Early MIS5e (∼133–128 ka) was dominated by hyperarid conditions in the Eastern Mediterranean–Levant, indicated by thick halite deposition triggered by a lake-level drop. Halite deposition was interrupted however, during the MIS5e peak (∼128–122 ka) by sequences of flood deposits, which are coeval with the timing of the intense precession-forced African monsoon that generated Mediterranean sapropel S5. A subsequent weakening of this humidity source triggered extreme aridity in the Dead Sea watershed and resulting in the biggest known lake level drawdown in its history, reflected by the deposition of thick salt layers, and a capping pebble layer corresponding to a hiatus at ∼116–110 ka. The DSDDP core provides the first evidence for a direct association of the African monsoon with mid subtropical latitude climate systems effecting the Dead Sea watershed. Combined with coeval deposition of Arabia and southern Negev speleothems, Arava travertines, and calcification of Red Sea corals, the evidence points to a climatically wet corridor that could have facilitated homo sapiens migration “out of Africa” during the MIS5e peak. The hyperaridity documented during MIS5e may provide an important analogue for future warming of arid regions of the Eastern Mediterranean–Levant
Advance Directives and End-of-Life Care: Completion, Conversations, and Concerns of Burlington Housing Authority Residents
Introduction: •An Advance Directive is a document that allows patients to declare their wishes regarding medical care and decision making should they become unable to communicate their preferences due to an accident or illness. •The Patient Self Determination Act, passed in 1991, requires that health care institutions, such as hospitals and nursing homes, inform patients of their rights to make health care decisions, the hospitals policies regarding recognition of Advance Directives, and educate the staff and community about advance care planning. •Despite the passage of this legislation, completion of Advance Directives remains low. It is estimated that less than 25% of adults nationwide have completed an Advance Directive.https://scholarworks.uvm.edu/comphp_gallery/1048/thumbnail.jp
Normalizing Resource Identifiers using Lexicons in the Global Change Information System: Linking Earth Science Identifiers, Concepts, and Communities
Earth Science informatics involves collaboration between multiple groups of people with diverse specializations and goals,often using variations in terminology to refer to common resources. The uniformity of the resource identifiers often does not cross organizational boundaries. Because of this, permanent, widely used, unambiguous identifiers for resources are elusive. We examine real world cases of changing and inconsistent identifiers which inherently work against persistence and uniformity. We also present a solution which mediates factors in these situations; namely the creation of lexicons:mappings of sets of terms to URIs which are curated within the Global Change Information System (GCIS). We discuss aspects of the GCIS which facilitate the use of lexicons: an information model which disambiguates resources, a RESTful API which provides metadata through content-negotiation, and a strategy for long term curation of URIs, including mechanisms for handling changes to URIs and variations in terms used by different communities while providing persistent URIs and preserving relationships between resources We provide working definitions of terms,contexts, and lexicons, and relate them to the practical challenges of disambiguation and curation. We also discuss the mechanisms employed and architecture of the GCIS, and how these choices facilitate representation of persistent identifiers and mappings of them to identifiers used colloquially within various earth science communities of practice
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