We report on the fabrication of a seven-cell-core and three-ring-cladding large-pitch Kagome-lattice hollow-core photonic crystal fiber (HC-PCF) with a hypocycloid-shaped core structure. We demonstrate experimentally and theoretically that the design of this core shape enhances the coupling inhibition between the core and cladding modes and offers optical attenuation with a baseline of ∼180 dB/km over a transmission bandwidth larger than 200 THz. This loss figure rivals the state-of-the-art photonic bandgap HC-PCF while offering an approximately three times larger bandwidth and larger mode areas. Also, it beats the conventional circular-core-shaped Kagome HC-PCF in terms of the loss. The development of this novel (to our knowledge) HC-PCF has potential for a number of applications in which the combination of a large optical bandwidth and a low loss is a prerequisite.

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This study describes memorials in the newly created “virtual cemeteries.” Web memorials ( N = 276) from three cemeteries were coded for demographics about the deceased, characteristics of authors, and issues of content, audience, and theme. While memorials were extremely varied, they were written frequently for the young ( M age = 47, SD = 24) and for more males than females. Most deaths were recent, but 7.3 percent had occurred more than twenty years prior to the posting of their memorials. Authors included family members, friends, and others who were typically younger or from the same cohort as the deceased. Most memorials were addressed to the community, but 28.3 percent were written to the dead. The majority of memorials were written as stories or celebrations but other primary themes included: grief/missing the dead, retelling the circumstances of the death, and guilt. Web memorials are discussed as a resource to the bereaved and researchers alike, providing the bereaved with an opportunity to create a public memorial regardless of their relationship to the deceased, time elapsed since the death or message content and allowing researchers better access to personal writings undertaken during bereavement.

Rheingold (1993) and others have described the potential for increased connectedness and community in cyberspace, but critics have charged that the Web increases social isolation rather than fostering interpersonal relationships. The present article explores how creating and visiting Web memorials (activities that initially appear isolating) affect the bereaved. Data from three studies on Web memorialization (descriptions of Web memorials, guestbook entries, and a survey of Web memorial authors) are used to examine three aspects of bereavement community: continuing bonds with the dead, strengthening existing relationships among the living, and creating new communities of the bereaved in cyberspace. Analysis suggests that rather than serving as a poor substitute for traditional bereavement activities, Web memorialization is a valued addition, allowing the bereaved to enhance their relationship with the dead and to increase and deepen their connections with others who have suffered a loss.

The prognostic value of preoperative serum levels of CA 19-9 and CEA was evaluated in 160 patients with pancreatic cancer. The survival of patients whose tumour marker value was below a certain cut-off level was compared with the survival of those with a higher value using the log-rank test. The lowest cut-off level dividing patients into groups with significant difference in survival (P < 0.05) was determined by graphical analysis of chi-square values at different cut-off levels. If stage of disease was not taken into account, there was a significant difference in survival between patients with low vs high preoperative CA 19-9 and CEA levels. When patients were classified according to stage, a difference was found for CA 19-9 in stage II-III patients. Patients with preoperative CA 19-9 below 370 U ml-1 had a significantly better prognosis than those with a higher level (P < 0.05). In stage I and stage IV patients, no significant difference was found between the groups at any cut-off level. The analysis of CEA showed a significant difference in survival only in stage IV patients, with CEA above 15 ng ml-1 being associated with shorter survival. In conclusion, in patients with stage II-III disease, particularly in patients with a non-resectable tumour, in whom the exact spread of the disease may be difficult to evaluate even at operation, the preoperative CA 19-9 level seems to have a prognostic value.