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[en] This volume attempts to establish the quantities of plutonium and highly enriched uranium (HEU) that existed in the early 1990s, and to identify the countries and forms in which they were held. It also presents scenarios of the amounts that may exist in the future, and considers some of the policy issues raised by these material inventories. Plutonium and highly enriched uranium are the essential materials in nuclear weapons. Knowledge of the scale and whereabouts of plutonium and HEU inventories is important for international security and nuclear non-proliferation. The comprehensiveness of this survey is such that no country is excluded and equal attention is given to civil and military materials. (Author)
[en] The issues and prospects for the future of the Non-Proliferation Treaty and regime at the review and extension conference in April 1995 are discussed. The civil applications and security concerns with regards to the nuclear energy in the Asia-Pacific region are outlined. Finally, the author examines Australia's position on nuclear energy its interests and policy and suggests what courses Australia should pursue in order to balance its political interests in the region with the wider non-proliferation/security interests which it shares with industrialized countries. The annexes contain the full text of the -Treaty on the non-proliferation of nuclear weapons- (5 March 1970) and of the -Agreed framework between the United States of America and the Democratic People's Republic of Korea-(21 October 1994). 81 refs., 5 tabs., 6 figs
[en] The projects of the two superpowers concerning the nuclear armament and intercontinental ballistic missiles, the policy of the two governments in monopoly of these armaments and prohibiting other countries from owning them, treaties signed by the governments, and the role of the United Nations and the International Atomic Energy Agency were presented
[en] Ubiquitin specific protease 39 (USP39) is one of the deubiquitinating enzymes without ubiquitin protease activity, which has been implicated in the progression of several cancers. However, the role of USP39 in pancreatic cancer (PC) is largely unknown. In present study, we found that USP39 expression was elevated in PC tissues than adjacent non-tumor tissues. Importantly, we demonstrated that overexpression of USP39 is closely correlated with tumor progression and poor survival in PC patients. Furthermore, high USP39 expression was observed in PC cell lines and ectopic expression of USP39 significantly enhanced in vitro cell proliferation and promoted in vivo tumor growth, whereas silencing USP39 suppressed growth of PC cells. Besides, our experimental data revealed that knockdown of USP39 induced cell apoptosis through inhibition of AKT signaling pathway in PC cells. Moreover, USP39 was a direct target of miR-133a, a microRNA that has been reported to be involved in progression of PC. Taken together, our data provide a novel PC regulatory axis that is miR-133a/USP39, the dysfunction of which drives diverse aspects of the progression of PC. - Highlights: • Upregulation of USP39 expression was significantly associated with the progression and poor survival in PC patients. • Overexpression of USP39 promotes PC cell growth in vitro and in vivo. • AKT pathway partly contributed to the oncogenic effects of USP39 in PC cells. • USP39 was found to be a direct target of miR-133a, which has been reported to be involved in progression of PC.
[en] The report covers the operations of the Australian Safeguards Office (ASO) and the Chemical Weapons Convention Office (CWCO) for the year ended June 1997. During this period, Australia has been an active and influential proponent in various activities aimed to strengthen the IAEA safeguard system. The principal development in this area during the 1996-1997 was the successful outcome of negotiations on a model protocol to provide IAEA with additional authority. Other activities outlined in the report have included, participation in international expert meetings, field trials of new safeguard procedures and techniques to assess their effectiveness, research and development into new safeguards technology. The Chemical Weapons Convention entered into force on 29 April 1997. As a consequence, the Australia's National Authority, CWCO formally became the national authority for CWC implementation. Up to that point CWCO had been engaged in preparations for entry into force, so that Australia was well prepared and able to make its initial declaration, both complete and on time. Sixty seven industrial chemical facilities were identified and declared under the CWC. CWCO collected the declaration information, and worked with companies to prepare them for any obligations they may have to meet. Links have been developed with a number of CWCO's overseas counterparts. enabling exchange of ideas and experiences related to practical implementation of the CWC. Both CWCO and ASO officers are able to act as national inspectors. The Director, CWCO can also appoint national inspectors who are not full time staff of the Office. This option will allow other relevant government officers, or persons with experience in chemical industry (perhaps retired from full time work), to act as national inspectors on a contract basis adding to CWCO's capabilities
[en] This review assesses, in policy terms, the accomplishments, prospects, and possible aftermath of the International Nuclear Fuel Cycle Evaluation (INFCE). Its origin and initial objectives, policy background, progress, and future prospects are considered. The authors conclude that the INFCE has served a useful purpose in developing a data base for both the proliferation risks and the benefits of the sensitive parts of the fuel cycle
[en] Scanning electron microscopy (SEM) allowed to observe B. bassiana and M. anisopliae adhesion and penetration structure on A. ipsilon larvae treated with the Lc50 of the fungus, B. bassiana revealed adhesion and penetration structures in the infected larvae. Growth of the fungus on the infected larvae and signs of hyphal penetration of insect cuticle as well as proliferation of the cuticle were also appeared. On the other hand, the fungus, M. anisopliaeas declared by SEM showed a dense network together and caused the green spores on the insect cuticle. Also, SEM allowed observing the spores and hyphae of the fungus in the body cavity of infected larvae. Scanning electron microscopy is convenient tools to observe the mode of action of entomopathogenic fungi and to observe how they are able to colonize and infect the host.
[en] The primary goal of this study is to frame the problem of nuclear proliferation in the context of protection and risks associated with nuclear materials flowing in the civilian nuclear fuel cycle. The perspective adopted for this study is that of a nuclear utility and the flow of fresh and spent nuclear fuel with which that utility must deal in the course of providing economic, safe, and ecologically acceptable electrical power to the public. Within this framework quantitative approaches to a material-dependent, simplified proliferation-risk metric are identified and explored. The driving force behind this search for such a proliferation metric derives from the need to quantify the proliferation risk in the context of evaluating various commercial nuclear fuel cycle options (e.g., plutonium recycle versus once-through). While the formulation of the algebra needed to describe the desired, simplified metric(s) should be straight forward once a modus operandi is defined, considerable interaction with the user of any final product that results is essential. Additionally, a broad contextual review of the proliferation problem and past efforts in the quantification of associated risks was developed as part of this study. This extensive review was essential to setting perspectives and establishing (feasibility) limits to the search for a proliferation metric(s) that meets the goals of this study. Past analyses of proliferation risks associated with the commercial nuclear fuel cycle have generally been based on a range of decision-analysis, operations-research tools. Within the time and budget constraints, as well as the self-enforced (utility) customer focus, the more subjective and data-intensive decision-analysis methodologies where not pursued. Three simplified, less-subjective approaches were investigated instead: a) a simplified 'four-factor' formula expressing as a normalized product political, material-quantity, material-quality, and material-protection metrics; b) a highly aggregated 'cost-equal-effort' or comparative-value method was applied to an array of commercial nuclear fuel forms in an effort to rank the attractiveness (to a proliferating agent) in terms of required effort as gauged through commercial costs; and c) the extension, if not actual application, of the system of Attractiveness Levels recommended by the USDOE as an extension and refinement of related IAEA protection-category guidelines. The Attractiveness-Level methodology, when compared to similar protection categories suggested by the IAEA, highlighted differences in required protection of specific source materials, with the IAEA being more conservative. From the viewpoint of a utility or research institute dealing with potential source materials, these differences can be important in budgetary terms. Both the 'cost-equal-effort' and the Attractiveness-Level methodologies were pursued to deal with conceptual and evaluation impasses encountered with the 'four-factor' formulation that were related primarily to the material-protection term necessary for its evaluation. The development, analyses, and evaluations performed to date on all three, inter-related approaches to simplified proliferation-risk metrics, as applied to the commercial nuclear fuel cycle, is reported. Key questions are discussed that must be resolved before a useful and simplified evaluation 'recipe' with which to evaluate proliferation risk and required protection levels (and cost) to nullify that risk is made available to the operator of a nuclear power plant and the total fuel cycle supporting it. (author)
[en] Parathyroid hormone-related protein (PTHrP), classically regarded as the mediator of the humoral hypercalcemia of malignancy syndrome, is a polyhormone that undergoes proteolytic processing into smaller bioactive forms. These bioactive forms comprise an N-terminal-as well as midregion-and C-terminal peptides, which have been shown to regulate various biological events, such as survival, proliferation and differentiation, in diverse cell model systems, both normal and pathological. A number of experimental data have demonstrated that PTHrP is also able to modulate tumor-relevant phenotypic expressions, thereby playing a role in early and advanced tumorigenesis, and in the response to treatment. In particular, interest has mainly been focused on the effects of PTHrP on cell proliferation/apoptosis, migration and invasion, which are the main roles involved in cancer development in vivo. The objective of this review is to discuss collectively the literature data on the molecular and biochemical basis of the mechanisms underlying the different, and sometimes opposite, effects exerted by PTHrP on various neoplastic cytotypes, with some final comments on both present and potential utilization of PTHrP as a target for anti-cancer therapy