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We describe the design and execution of the BORTAS (Quantifying the impact of BOReal forest fires on Tropospheric oxidants using Aircraft and Satellites) experiment, which has the overarching objective of understanding the chemical aging of airmasses that contain the emission products from seasonal boreal wildfires and how these airmasses subsequently impact downwind atmospheric composition. The central focus of the experiment was a two-week deployment of the UK BAe-146-301 Atmospheric Research Aircraft (ARA) over eastern Canada. The planned July 2010 deployment of the ARA was postponed by 12 months because of activities related to the dispersal of material emitted by the Eyjafjallajökull volcano. However, most other planned model and measurement activities, including ground-based measurements at the Dalhousie University Ground Station (DGS), enhanced ozonesonde launches, and measurements at the Pico Atmospheric Observatory in the Azores, went ahead and constituted phase A of the experiment. Phase B of BORTAS in July 2011 included the same measurements, but included the ARA, special satellite observations and a more comprehensive measurement suite at the DGS. The high-frequency aircraft data provided a comprehensive snapshot of the pyrogenic plumes from wildfires. The coordinated ground-based and sonde data provided detailed but spatially-limited information that put the aircraft data into context of the longer burning season. We coordinated aircraft vertical profiles and overpasses of the NASA Tropospheric Emission Spectrometer and the Canadian Atmospheric Chemistry Experiment. These space-borne data, while less precise than other data, helped to relate the two-week measurement campaign to larger geographical and longer temporal scales. We interpret these data using a range of chemistry models: from a near-explicit gas-phase chemical mechanism, which tests out understanding of the underlying chemical mechanism, to regional and global 3-D models of atmospheric transport and lumped chemistry, which helps to assess the performance of the simplified chemical mechanism and effectively act as intermediaries between different measurement types. We also present an overview of some of the new science that has originated from this project from the mission planning and execution to the analysis of the ground-based, aircraft, and space-borne data.

To examine the type of published research regarding quality of life for cancer patients over two 24-month periods: 1995-1996 and 2005-2006. A computer-based literature search was conducted using Medline. Two random samples of 120 publications identified in 1995-1996 and in 2005-2006 were coded as data-based research, reviews or programme descriptions. Data-based publications were further coded as measurement, descriptive or intervention research. Intervention publications were coded as psychosocial- or biomedical-based. Psychosocial intervention papers were coded using Cochrane Review criteria. In 1995-1996, 419 publications were identified and 1271 publications in 2005-2006. The majority of publications were data-based. The proportion of types of publications (data-based, reviews or programme description/case report categories) did not change significantly over time. Descriptive research dominated data-based publication outputs in 1995-1996 and 2005-2006. The current approach to quality of life research for cancer patients may be less than optimal for providing successful development of knowledge, improving healthcare delivery and lessening the burden of suffering.

As a result of more people living with or surviving cancer, outputs for quality of life research may have increased over time to reflect the needs of the growing number of people affected by cancer. To determine if this is the case, the authors sought to examine the number and proportion of publications concerned with cancer patients' quality of life for four major cancer sites (breast, lung, prostate, colorectal) over five equal time periods (1985, 1990, 1995, 2000, 2005). A computer-based literature search using Medline and PsycINFO databases was undertaken. A comparison search with cancer-related biomedical terms was conducted. The results showed that the number of quality of life publications was substantially lower compared with biomedical publications over time, although the average annual relative increase in publications was greatest for quality of life. The total number of quality of life publications was greatest for breast cancer and lowest for colorectal cancer at all five time points. The relative increase over time of quality of life publications was greatest for prostate cancer and lowest for breast cancer. More research is needed regarding quality of life for cancer patients. Breast cancer has dominated quality of life research outputs despite a lower relative increase in publications over time compared with other cancer sites. There is need for debate among funding agencies and researchers to ensure research efforts are shared among cancer types.

Records for more than 2,000 individuals seen in the Dentofacial Clinic of the University of North Carolina were examined to evaluate trends in referral patterns for orthognathic surgery and acceptance of surgical treatment The vast majority of patients have been white and female from the beginning, and the female-male ratio remained constant at 2:1 throughout the 1990s. The proportion of nonwhite patients increased significantly after 1995, with the change resulting almost totally from more Hispanic and Asian patients. The proportion of African Americans, who represent 22% of the general population, remained almost constant at 10%. Class III and long-face individuals were more likely to seek evaluation than those with Class II problems, but of those who were offered orthognathic surgery, relatively more of the Class II group accepted it. This may reflect greater severity of a Class II problem before a patient seeks treatment. More than 1 of the Clinic population had some sort of facial asymmetry, but the presence of asymmetry did not seem to influence the decision to have surgical treatment. The dental and skeletal characteristics of those who had surgery were similar to those of patients who did not have surgery, suggesting that the decision to elect a surgical treatment plan was influenced by factors other than clinical characteristics.

Skeletal changes greater than those observed in untreated adults have been noted beyond 1 year post-surgery in adult patients who had surgical correction of a long face deformity. The stability of skeletal landmarks and dental relationships from 1 to3 years post-surgery was examined in 28 patients who had undergone surgery of the maxilla only, and in 26 patients who had undergone 2-jaw surgery to correct2 mm anterior open bite. Although the average changes in almost all landmark positions and skeletal dimensions were less than 1 mm, point B moved down2 mm and face height increased2 mm in one-third of the maxilla-only group and in 40% of the 2-jaw group (4 mm in 10% and 22% respectively). Overbite decreased 2-4 mm in only 7% of the maxilla-only and 12% of the 2 groups, with no changes4 mm, because in three-fourths of the patients with an increase in anterior face height, further eruption of the incisors maintained the overbite relationship. In the maxilla-only group, mandibular length (Co-Pg) showed2 mm long-term change in 45% of the patients, two-thirds of whom showed an increase rather than a decrease in length. In the 2-jaw group, no patients showed a decrease in Co-Pg length and one-third had an increase. For both groups, changes in overjet were smaller and less frequent than changes in mandibular length.

A surprisingly large amount of long-term remodeling of facial structures has been noted in the period between 1 and 5 years post-orthognathic surgery. To evaluate whether these changes are greater than in patients with similar morphology who did not have surgery, long-term changes in hard tissue landmarks were examined in 33 untreated adults and compared to long-term changes in skeletal Class II surgery patients who underwent maxillary impaction, mandibular advancement, or both. Although the changes were small in both groups, mean changes were greater in the surgical patients; the surgical patients also showed a higher percentage of significant changes. Horizontal changes were in a forward direction in the untreated group and a backward direction in the surgical groups. We conclude that normal adult growth cannot account for the long-term changes observed following jaw surgery. In some instances, postsurgical changes leading to relapse continue much longer than would have been expected.

To evaluate long-term changes after surgical correction of skeletal Class III deformity, postoperative cephalometric radiographs at 1 year and 2 or more years postsurgery were digitized for 92 patients who had received either a bilateral sagittal split osteotomy for mandibular setback, Le Fort I maxillary advancement, or a combination of the two procedures. Patients' perceptions of treatment were determined by four self-administered questionnaires: satisfaction, postsurgical perception of occlusion and function, problems with facial sensation, and postsurgical perceptions. From 1 year to longest follow-up, there were almost no mean changes in landmark positions for the maxillary advancement group and minimal mean changes in the mandibular setback and two-jaw groups. In all three groups, more than 90% of the patients showed no clinically significant long-term changes, which suggests that long-term changes are less likely after Class III than Class II treatment. At long-term recall, 89% of the patients expressed satisfaction with their treatment and would recommend it to others, 74% reported improved social interaction, and 63% said their appearance changed as they expected. The predominant problems reported were altered facial sensation for 67% of the patients and surprise at the length of recovery for 52%.

The assumption is often mode that the soft tissue changes resulting from orthognathic surgery have stabilized by 6 to 12 months, but longer-term changes may differ from the normal aging process observed in nonsurgical patients. Soft tissue changes that occurred between 1 year and 3 to 5 years post-surgery in 79 orthognathic surgery patients who had received either a bilateral sagittal split osteotomy or a Le Fort I osteotomy in conjunction with a bilateral sagittal split osteotomy were compared to those experienced by a group of 36 patients who had received only orthodontic treatment. Although soft tissue changes did occur, there were no significant differences between average annualized soft tissue changes in the three treatment groups.

Long-term changes in soft tissue landmark positions were examined in 49 patients following superior repositioning of the maxilla by Le Fort I osteotomy. From presurgery to 1 year, on average the upper lip moved up one third the distance that the upper incisor and point A did, but there was considerable variability. In 25% of the patients the upper lip moved up more than 2 mm, and in 6% it moved up more than 4 mm. As the mandible rotated upward and forward in response to the maxillary movement, soft tissue movements paralleled the adjacent hard tissue movements almost exactly in the absence of genioplasty. From 1 to 5 years postsurgery, in 25% of the patients the maxilla moved downward more than 2 mm, and the mandible rotated down and back, often without relapse of occlusal relationships. In both jaws, long-term changes in soft tissue landmarks exceeded hard tissue changes, meaning soft tissue points tended to move downward even if hard tissue points were stable and moved down more than the corresponding hard tissue points when skeletal changes occurred.

Changes in dental and skeletal relationships were evaluated 5 years postsurgically in 49 patients whose maxilla had been superiorly repositioned by a Le Fort I osteotomy. All of the patients had at least 2 mm of intrusion at the maxillary incisor and molar; none had a mandibular ramus osteotomy or other osteotomy except genioplasty. Only 6.5% had 2 mm or greater of net vertical change in skeletal or dental landmarks at 1 year postsurgery. From 1 to 5 years postsurgery, minimal changes in skeletal and dental landmarks occurred in the majority of the patients, but approximately 25% of the patients showed 2 mm or more of downward movement of the maxilla and/or eruption of maxillary teeth, leading to downward-backward rotation of the mandible. Only one patient had more than 1 mm of open bite on long-term follow-up. An increase in overbite, resulting from incisor eruption, was noted in 14%, and an increase in overjet occurred in 12% as the mandible rotated. It appears that modest long-term skeletal and dental changes occur in some surgically treated long-face patients. The likelihood of long-term change was not related to the age of the patient, stability during the first postsurgical year, or segmentation of the maxilla at surgery.

The aims of this study were to evaluate the changes in the facial profile related to maxillary incisor retraction and to check for correlations between changes in the lip and changes in the positions of the teeth and alveolar bone during orthodontic treatment. Initial and final lateral cephalometric radiographs of 25 nongrowing Brazilian patients were selected for this study. All patients initially presented with Class I or II malocclusions and had their maxillary incisors retracted at least 2 mm during orthodontic treatment. Changes in lip position, length, and width, as well as changes in the positions of the alveolar bones and incisors, were calculated. Statistically significant differences from pretreatment to posttreatment were observed for all measurements except for upper lip length and point A. A high correlation was demonstrated between changes in the lower lip sulcus and point B and between changes in the lower lip sulcus and the mandibular incisor. Changes in the maxillary and mandibular incisors did not show a high correlation to the total lip changes, but high correlation coefficients were obtained when the changes in lip width were excluded from the total lip changes. In other words, changes in lip width tended to mask the changes in lip position caused by retraction of the maxillary incisors.

Previous studies have reported revascularization and reorganization of dental pulp chambers with periodontal tissues of monkeys following complete surgical transection through a portion of the apical roots. This study observed 128 teeth in four adult monkeys. Following surgical transection, the tissues were acquired by perfusion fixation, serially sectioned, and stained for cellular detail with hematoxylin and eosin. Collagen tissues were stained with Preece's trichrome and neural tissues with Rowles' silver cyanate for controlled impregnation. At 1 and 2 weeks the coronal tissues showed tissue disruption, necrosis, and degenerating nerves. The 3- and 4-week tissues that had been completely transected showed replacement healing of the pulp tissue with periodontal ligament connective tissue, but no nerves were present. At 6 weeks, no nerves were present in the coronal chambers of those teeth with complete vital transection. The 24-, 36-, and 52-week pulp chambers with complete transection failed to show nerve fibers in their reorganized connective tissues.

Previous workers have obtained by electron-diffraction from liquid-mercury surfaces either evidence of a crystalline structure, which they attributed to the mercury, or inconclusive results in that only incoherent scattering was observed. The present work explains these discrepancies and shows that liquid-mercury surfaces are in reality amorphous, but are generally covered with a thin crystalline film of some adventitious impurity.

(1950). Electrodeposition on Aluminium—A Study of the Zincate Process. Transactions of the IMF: Vol. 27, No. 1, pp. 233-260.

While the consumption of all the common non-ferrous metals added together falls far short of that of iron and steel, our civilization owes to them almost as much as to the cheaper and more abundant ferrous metals. One has only to think of copper conductors, aluminium airframes and cooking utensils, galvanized steel, tinplate food containers and of lead water-pipes and cable sheaths to see illustrated some of the special properties through which these metals make their essential contribution to our attempts to live in civilized communion. This country is not richly endowed with natural resources of the non-ferrous metals, for supplies of which it is fortunately able to rely largely on other Commonwealth countries.

A method is described by which the surface tension of surfaces occurring in the systems copper-hydrogen or argon and copper-lead-hydrogen or argon is determined. At temperatures round 850° C the surface tension between copper grains is 640 dyne/cm. and between copper and the equilibrium lead-copper liquid phase 340 dyne/cm. The surface tension of a copper-gas surface is the same whether the gas is hydrogen or argon, within the limits of precision of the experiment, and has the value 1,800 dyne/cm. When lead vapour is present in the gas atmosphere at a partial pressure of the order of 0.1 mm. Hg the surface tension of the copper-gas surface has the much lower value of 780 dyne/cm It is suggested that the reduction is due to the adsorption of lead at the copper-gas surface The failure of the liquid phase to exhibit a contact angle of zero against solid copper surfaces is thereby understood

Chick embryos were injected with [3H]-thymidine at days 3-7 of incubation and were fixed and embedded in plastic. The embryos were divided into three stage groupings of development [Hamburger and Hamilton: J Morphol 88:49-92, 1951], and labeling indices were determined for each of the following delineated regions within the maxillary process at each stage: region 1, subepithelial mesenchyme located at the medial side of the maxillary process adjacent to the roof of the stomodeum; region 2, subepithelial mesenchyme at the ventral tip of the maxillary process (as seen on cross section); region 3, subepithelial mesenchyme at the lateral portion of the maxillary process below the eye; and region 4, interior mesenchyme defined as the central portion of the maxillary process and separated from the epithelium by the three other regions. Results indicated that differences exist among the regions examined and that these differences were stage specific. At stages 19-21 and stages 24-25 1/2, growth rates were higher in subepithelial regions than interiorly. At stages 28-29, however, a statistically significant difference among the regions was not found. These results suggested that there is an association between growth rates in the maxillary process mesenchyme and its proximity to the overlying epithelium and that these effects are related to the stage of development.

By Donald McDonald London: Johnson Matthey & Co. Ltd. Pp. 254. Price 35s. In view of their permanence the metals of the platinum group have long had a special place in the pursuit of the basic sciences. As a consequence they have now become indispensable materials of use in a wide range of industries.