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Management of the neck in patients treated with primary chemoradiation for cancer of the laryngopharynx with a clinically positive neck remains an area of controversy. The neck may be managed in 1 of 3 ways: by observation, by planned neck dissection, or by salvage neck dissection. Observation of the neck can be done in patients who have a complete or near-complete response to treatment and have a negative positron emission tomography (PET) scan result. Evidence for this approach comes from recent studies that have reported low regional recurrence rates.1–6 Planned neck dissection was carried out in the past in patients with N2 and N3 neck disease irrespective of the response to chemoradiation. The neck dissection was carried out 6 weeks after completion of chemoradiation; this approach had the advantage of carrying out the neck dissection before the onset of fibrosis, thereby making the neck dissection technically similar in complexity to a nonchemoradiation neck dissection. Evidence for a policy of planned neck dissection comes from studies that have shown the presence of tumor in neck dissection specimens in patients who have complete or near-complete radiologic and clinical response in the neck.4,7–10 Before the introduction of fluorodeoxyglucose–positron emission tomography (FDG-PET) scanning, planned neck dissection was a common method for managing the neck after chemoradiation. Some groups still practice this policy because of limitations or unavailability of PET. However, in general, most centers now reserve neck dissection for salvage for residual or recurrent neck disease. Salvage neck dissection is normally carried out if there is clinical or radiologic evidence of neck disease after completion of chemoradiation. Before 2005, our policy was to assess response by clinical examination and CT imaging at 6 to 12 weeks after completion of chemoradiation. However, since 2005, we have been using 18FDG-PET for the assessment of tumor response. The 18FDG-PET is usually carried out at 12 weeks after completion of chemoradiation to minimize any false-positive results from residual inflammation from chemoradiation. Salvage neck dissection in patients who have neck disease as detected by PET is therefore carried out 12 weeks after chemoradiation. This has the disadvantage of making the operation technically more difficult because of the onset of fibrosis. As a consequence, some have advocated the use of selective and superselective salvage neck dissections in these patients.11–14 Clearly there is evidence in the literature to support the practice of planned, as well as salvage neck dissection. However, there is little in the literature that describes what the impact of viable tumor in such neck dissection specimen has on prognosis. In this study, we have examined our own experience of patients undergoing comprehensive neck dissection either as a planned procedure or salvage procedure in the time period before our routine use of PET. The objective was to determine whether viable tumor had a negative impact on prognosis, even after removal of residual tumor by neck dissection.

The Innamincka Dome and associated low-gradient fan in the Strzelecki Desert is the product of Cenozoic crustal warping that has aided formation of an extensive array of palaeochannels, source-bordering transverse dunes and superimposed linear dunes. These dunes have impeded the course of Cooper Creek and provided a repository of evidence for Quaternary climate change as well as the interactive processes between transverse and linear dune formation. At Turra, Gidgealpa and sites nearby are extensive fluvial and aeolian sand bodies that date from marine isotope stages (MIS) 8–3 and the Last Glacial Maximum (LGM) and are now surrounded or buried by overbank mud. The sandy alluvium was deposited on the downstream slope of the dome by large channels transporting abundant bedload, subsequently blown northward to form transverse dunes from what were probably seasonally-exposed bars in a palaeo-Cooper system. Thermoluminescence (TL) and optically stimulated luminescence (OSL) ages demonstrate that the base of the dune complex is at least MIS 7 in age (∼250 ka) but that it has been subsequently reworked by wind with additional sand blown from the river. Source-bordering dunes formed during a period of enhanced river flow and sand supply from ∼120 to 100 ka, with another short episode of the same at ∼85–80 ka and from ∼68 to 53. The LGM was associated with enhanced flows and the supply of dune sediment, from 28 to 18 ka. Pronounced river flow and dune activity occurred in the early to mid Holocene, but there is no evidence of dunes being supplied from Cooper Creek since the LGM. The dunes forming the oldest basal sand units appear to be largely transverse in form and are aligned roughly parallel to adjacent east–west trending palaeochannels. Linear dunes have formed from and over these, and yield basal ages ranging from MIS 5 or MIS 4 but continuing to accrete and rework through to the Holocene. The study results in one of the few detailed chronological investigations of the interaction between transverse and linear dunes. It is apparent that long-distance sand transport has played no significant role in dune formation here for the linear dunes show no significant downwind decline in ages. Linear dunes appear to have accreted vertically from underlying transverse dunes. A wind-rift vertical accretion model with only minor lengthwise extension is the dominant mode of linear dune formation in this section of the Strzelecki Desert, the bulk of dune sediment being sourced from adjacent swales since the LGM.

As a low-gradient arid region spanning the tropics to the temperate zone, the Lake Eyre basin has undergone gentle late Cenozoic crustal warping leading to substantial alluvial deposition, thereby forming repositories of evidence for palaeoclimatic and palaeohydrological changes from the Late Tertiary to the Holocene. Auger holes and bank exposures at five locations along the lower 500 km of Cooper Creek, a major contributor to Lake Eyre in the eastern part of the basin, yielded 85 luminescence dates (TL and OSL) that, combined wit a further 142 luminescence dates from northeastern Australia, have established a chronology of multiple episodes of enhanced flow regime from about 750 ka to the Holocene. Mean bankfull discharges on Cooper Creek upstream of the Innamincka Dome at 250-230 ka or oxygen isotope stages (OIS) 7-6 are estimated to have been 5 to 7 times larger than those of today, however, substantially less reworking has occurred during and after OIS 5 than before. Lower Cooper Creek appears to have similarly declined. In the Tirari Desert adjacent to Lake Eyre there is evidence of widespread alluvial activity, perhaps during but certainly before the Middle Pleistocene, yet the river became laterally restricted in OIS 7 to 5. While the Quaternary has been characterised by a dramatically oscillating wet-dry climate, since oxygen isotope stage OIS 7 or 6 there has been a general decline in the magnitude of the episodes of wetness to which the eastern part of central Australia has periodically returned. During the last full glacial cycle, Cooper Creek's periods of greatest runoff and sand transport were not during the last interglacial maximum of OIS 5e (132-122 ka) but later in OIS 5 when sea levels and global temperatures were substantially below those of 5e or today. Fluvial activity returned in OIS 4 and 3, but not to the extent of mid and late OIS 5; strongly seasonal but still powerful flows transported sand and fed source-bordering dunes in OIS 5 and 3. This chronology of fluvial activity in the late Quaternary broadly coincides with that for rivers of southeastern Australia and suggests that the wet phases in eastern central Australia have not been governed as much by the northern monsoon as by conditions in the western Pacific close to the east coast both north and south. Flow confinement within the Innamincka Dome has locally amplified Cooper Creek's energy, and here evidence exists for short but high-magnitude episodes of flow during the Last Glacial Maximum and in the early to middle Holocene, conditions that were capable of forming large palaeochannels but that were not long-lived enough to rework the river's extensive floodplains elsewhere along its length.

Audience members are camped on the floor. Pressure-sensing mats and a backprojected screen delineate a performance space. Cameras trained on this space include a live-projected feed, as well as a number of smaller motion-sensing cameras. The performer first appears as silhouette. Notes sound as she moves. As she emerges into the space, her steps launch further notes while her gestures trigger flurries of other pitches. Video-effects shimmer, delay or multiply her projected image when she moves. Sometimes engrossed in inner movementdialogue, at other times she turns attention to the audience, mirroring their postures, dissolving the distance between them. Later, by playfully jogging around or gently nudging audience members, she wordlessly encourages their participation. Finding some willing collaborators, a number of ad hoc movement-duets unfold. One spectator initiates a duet himself. Performance over, the audience are encouraged to investigate the space themselves. The invitation is enthusiastically accepted.

This was a two-year project that had two major components: 1) the demonstration of a PV-electrolysis system that has separate PV system and electrolysis unit and the hydrogen generated is to be used to power a fuel cell based vehicle; 2) the development of technologies for generation of hydrogen through photoelectrochemical process and bio-mass derived resources. Development under this project could lead to the achievement of DOE technical target related to PEC hydrogen production at low cost. The PEC part of the project is focused on the development of photoelectrochemical hydrogen generation devices and systems using thin-film silicon based solar cells. Two approaches are taken for the development of efficient and durable photoelectrochemical cells; 1) An immersion-type photoelectrochemical cells (Task 3) where the photoelectrode is immersed in electrolyte, and 2) A substrate-type photoelectrochemical cell (Task 2) where the photoelectrode is not in direct contact with electrolyte. Four tasks are being carried out: Task 1: Design and analysis of DC voltage regulation system for direct PV-to-electrolyzer power feed Task 2: Development of advanced materials for substrate-type PEC cells Task 3: Development of advanced materials for immersion-type PEC cells Task 4: Hydrogen production through conversion of biomass-derived wastes

Linear dunes are the most abundant type of desert dune and the dominant land-form on the continent of Australia. This paper reports the results of GPR surveys across linear dunes in the deserts of central Australia including parts of the Simpson and Strzelecki deserts. The GPR data suffered from severely limited penetration and poor resolution due to signal attenuation associated with a high proportion of mud, which, probably due to progressive illuviation, increases with dune age. However, although such conditions prevail in much of central Australia, useful stratigraphic information can still be obtained there using GPR. Buried palaeosol horizons within dunes have been identified, and taken in conjunction with thermoluminescence (TL) ages from the dunes, it is possible to make some interpretations of linear dune evolution. TL ages show that some dunes are older in the south and young toward the north. It is possible to place some constraints on rates of vertical, lateral, and dune-front accretion within the linear dunes with ∼ 2-6 m, 0-50 m and 3000 m, respectively, over the last ca. 10 ka. The combination of GPR profiles and TL dating of linear dunes in the Simpson and Strzelecki deserts confirms Holocene modification of preexisting linear dunes with minor easterly accretion that has contributed to the asymmetry of vegetated linear dunes in central Australia. The results support the hypothesis that linear dunes in Australia are composite forms with a long and sometimes complex history. © 2007 The Geological Society of America. All rights reserved.

Objective To describe the clinicopathologic and radiologic features of solitary fibrous tumors of the head and neck. Design Retrospective analysis. Setting Tertiary referral center that performs head and neck surgical oncology. Patients Twelve patients with solitary fibrous tumors of the head and neck identified from the pathology and soft tissue tumor databases at Memorial Sloan-Kettering Cancer Center, New York, NY, from 1990 to 2004. All cases were reviewed by 3 experienced pathologists, 1 of whom is an experienced soft tissue tumor pathologist. The diagnosis was confirmed by microscopic features on hematoxylin-eosin staining and by positive staining for CD34 and Bcl2 on immunohistochemical analysis. Tumors were scored for mitotic activity, cellularity, nuclear pleomorphism, necrosis, and the presence of a malignant component. Details on patient characteristics, tumor characteristics, previous treatment and surgery, adjuvant treatment, and outcome were recorded from clinical records. Results Solitary fibrous tumors occurred in patients over a wide age range (27-78 years; median age, 52 years). Seven patients (58%) were women, and 5 (42%) were men. Most tumors presented as a slow-growing painless mass with a duration ranging from 2 months to 5 years. The tumors ranged from 1 × 1 cm to 6 × 5 cm. Patients presented with a subcutaneous mass of the scalp or face in 4 cases, intraoral mass in 4, sinonasal mass in 3, and paraspinal mass in 1. Computed tomographic and/or magnetic resonance imaging scans of 7 of the 12 patients showed well-circumscribed tumors that enhanced strongly with contrast. Treatment for all of the patients was surgical resection. Pathologic findings showed that 9 tumors were benign and 3 were malignant. Three patients had a positive surgical resection margin. All patients were alive at a median follow-up of 8 months (range, 1-76 months). Local recurrence occurred in 1 patient who had positive surgical margins 3 years after the initial surgery. Conclusions Solitary fibrous tumors of the head and neck region are rare and most commonly benign. The diagnosis depends on microscopic and immunohistochemical features, although imaging may help. Patients with these tumors can be safely treated with local excision, but tumors with positive margins require close follow-up over several years owing to the potential for late local recurrence.

Objective To report our experience in treating patients with malignant minor salivary gland tumors of the larynx. Design Thirty-three-year retrospective study. Setting Tertiary referral center specializing in head and neck surgery. Patients Twelve patients with malignant minor salivary gland tumors of the larynx were identified from a search of the institutional databases and pathology records at Memorial Sloan-Kettering Cancer Center, New York, NY, between the years 1970 and 2003. All slides were independently reviewed by 2 pathologists (R.G. and D.C.). Details on patient and tumor characteristics, as well as treatment and surgical outcome, were recorded. Results Ten patients (83%) had adenoid cystic carcinoma and 2 (17%) had myoepithelial carcinoma. Five (42%) were located in the supraglottis and 7 (58%) in the subglottis. Ten (83%) had surgery (6 with adjuvant radiotherapy) and 2 (17%) were treated with radiotherapy alone. Of the 10 patients who had surgery, total laryngectomy was required in 6 (60%), supraglottic horizontal laryngectomy in 2 (20%), and cricotracheal resection in 2 (20%). With a median follow-up of 55 months (range, 1-194 months), 10 patients are alive, 6 of whom have no evidence of disease. Seven patients (58%) developed recurrent disease, 2 of whom had local recurrence alone, 1 had regional recurrence alone, 3 had distant recurrence alone, and 1 had local and distant recurrence. Conclusions Up to 60% of patients with malignant minor salivary gland tumors of the larynx will develop recurrent disease locally, regionally, or at distant sites. In adenoid cystic carcinoma, regional recurrence is rare, but distant recurrence is common and may occur up to 10 years after the index therapy. For both adenoid cystic and myoepithelial carcinoma, partial surgery is possible in selected cases, but because of the high propensity for submucosal spread and perineural and lymphovascular invasion, total laryngectomy is usually recommended.