Academic literature on the topic 'Fire scar history'

Fire scars are widely used to reconstruct fire history, yet patterns of scarring are poorly understood, hampering effective sampling and analysis. Factors that influence the probability a tree will receive a scar (SP) and the fraction of trees that scar (SF) are little studied. We analyzed scarring in 16 fires in ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) forests in northern Arizona. SP was significantly related to char height, presence of a preceding scar, tree diameter, and years since a preceding fire. Mean SF was 0.375, but varied from 0.121 to 0.728, with SF significantly higher with higher mean char height, larger scar dimensions, higher fire severity, larger tree diameter, and where no preceding fire had burned within 30 years. The expected healing times exceeded 55 years for 33% of scars and 100 years for 11% of scars. Scars with a preceding scar were 38% larger than new scars, with expected healing about 20–25 years longer. Scars were clustered, particularly at scales from >20 to >40 m. Scar directions generally aligned with fire-spread directions, which were complex. Variability in SF complicates fire-history methods that use fire counts rather then area burned. Methods that account for spatial and temporal variability in the abundance of evidence are needed.

Abstract. Fire history reconstructions are typically based on tree ages and tree-ring fire scars or on charcoal in sedimentary records from lakes or bogs, but rarely on both. In this study of fire history in western Patagonia (47–48° S) in southern South America (SSA) we compared three sedimentary charcoal records collected in bogs with tree-ring fire-scar data collected at 13 nearby sample sites. We examined the temporal and spatial correspondence between the two fire proxies and also compared them to published charcoal records from distant sites in SSA, and with published proxy reconstructions of regional climate variability and large-scale climate modes. Two of our three charcoal records record fire activity for the last 4 ka yr and one for the last 11 ka yr. For the last ca. 400 yr, charcoal accumulation peaks tend to coincide with high fire activity in the tree-ring fire scar records, but the charcoal records failed to detect some of the fire activity recorded by tree rings. Potentially, this discrepancy reflects low-severity fires that burn in herbaceous and other fine fuels without depositing charcoal in the sedimentary record. Periods of high fire activity tended to be synchronous across sample areas, across proxy types, and with proxy records of regional climatic variability as well as major climate drivers. Fire activity throughout the Holocene in western Patagonia has responded to regional climate variation affecting a broad region of southern South America that is teleconnected to both tropical- and high-latitude climate drivers-El Niño-Southern Oscillation and the Southern Annular Mode. An early Holocene peak in fire activity pre-dates any known human presence in our study area, and consequently implicates lightning as the ignition source. In contrast, the increased fire activity during the 20th century, which was concomitantly recorded by charcoal from all the sampled bogs and at all fire-scar sample sites, is attributed to human-set fires and is outside the range of variability characteristic of these ecosystems over many centuries and probably millennia.

Abstract. Fire history reconstructions are typically based on tree ages and tree-ring fire scars or on charcoal in sedimentary records from lakes or bogs, but rarely on both. In this study of fire history in western Patagonia (47–48° S) in southern South America (SSA) we compared three sedimentary charcoal records collected in bogs with tree-ring fire-scar data collected at 13 nearby sample sites. We examined the temporal and spatial correspondence between the two fire proxies and also compared them to published charcoal records from distant sites in SSA, and with published proxy reconstructions of regional climate variability and large-scale climate modes. Two of our three charcoal records show fire activity for the last 4ka yrs and one for the last 11 ka yr. For the last ca. 400 yr, charcoal accumulation peaks tend to coincide with high fire activity in the tree-ring fire scar records, but the charcoal records failed to detect some of the fire activity recorded by tree rings. Potentially, this discrepancy reflects low-severity fires that burn in herbaceous and other fine fuels without depositing charcoal in the sedimentary record. Periods of high fire activity tended to be synchronous across sample areas, across proxy types, and with proxy records of regional climatic variability as well as major climate drivers. Fire activity throughout the Holocene in western Patagonia has responded to regional climate variation affecting a broad region of southern South America that is teleconnected to both tropical- and high-latitude climate drivers – El Nino-Southern Oscillation and the Southern Annular Mode. An early Holocene peak in fire activity pre-dates any known human presence in our study area, and consequently implicates lightning as the ignition source. In contrast, the increased fire activity during the 20th century, which was concomitantly recorded by charcoal from all the sampled bogs and at all fire-scar sample sites, is attributed to human-set fires and is outside the range of variability characteristic of these ecosystems over many centuries and probably millennia.

Determining forest fire history is commonly based on fire scar dating with dendrochronological methods. We used an experimental setup to investigate the impacts of low-intensity prescribed fire on fire scar formation 8 years after fire in 12 young managed Scots pine (Pinus sylvestris L.) stands. Five stands were between 30 and 35 years old and seven were 45 years old at the time of burning. A total of 217 fire scars were recorded in 142 trees. The number of separate scars per tree originating from a single fire ranged from 1 to 6, with 67% of the trees having just one scar. The proportion of fire-scarred trees out of all trees per plot ranged from 0% to 30%, averaging 16.5% in young stands and 2.8% in older stands. Four of the 12 burned plots did not have any trees with fire scars, and these were all in the older age group. This means that in the older stands, in only three of seven plots (43%) did the fire leave scars from which fire can potentially be detected and dated afterwards. Our results suggest that fire scar dating in Scots pine dominated forests may underestimate fire frequency, area, and the importance of historically common low-intensity surface fires in dendrochronological reconstructions of past fire histories.

We used maps of fire evidence, fire scar dendrochronology, forest age-structure analysis, and landscape analysis to investigate fire history at pinyon pine ( Pinus edulis Engelm.) – juniper ( Juniperus osteosperma (Torr.) Little, Juniperus scopulorum Sarg.) woodland – ponderosa pine ( Pinus ponderosa P. & C. Lawson) forest ecotones in Arizona (Tusayan) and in New Mexico (Canjilon). Results showed that charred trees were not evenly distributed across vegetative communities but were significantly (p < 0.001) more abundant than expected in ponderosa pine communities. Composite fire scar analysis indicated that surface fires occurred in ponderosa pine stands at both sites and burned at intervals of 7.2–11.1 years (WMPI; Weibull median probability interval). At Tusayan, landscape structure was fine grained, and maximum pinyon age was >200 years across 80% of the site. At Canjilon, landscape pattern was relatively coarse, and most pinyon patches were 200–300 years old. Cumulative standing age distributions suggested pinyon–juniper fire rotations of 340 and 290 years at Tusayan and Canjilon, respectively. We concluded the following: (i) surface fires in ponderosa pine stands did not spread through pinyon–juniper communities at either site, (ii) fire evidence was prevalent across both sites, but old pinyon trees indicated that no widespread lethal fires had occurred in the last 300–400 years, and (iii) structurally heterogeneous landscapes suggested that historical pinyon–juniper fires were of limited extent but lethal in patches.

Present understanding of fire ecology in forests subject to surface fires is based on fire-scar evidence. We present theory and empirical results that suggest that fire-history data have uncertainties and biases when used to estimate the population mean fire interval (FI) or other parameters of the fire regime. First, the population mean FI is difficult to estimate precisely because of unrecorded fires and can only be shown to lie in a broad range. Second, the interval between tree origin and first fire scar estimates a real fire-free interval that warrants inclusion in mean-FI calculations. Finally, inadequate sampling and targeting of multiple-scarred trees and high scar densities bias mean FIs toward shorter intervals. In ponderosa pine (Pinus ponderosa Dougl. ex P. & C. Laws.) forests of the western United States, these uncertainties and biases suggest that reported mean FIs of 2-25 years significantly underestimate population mean FIs, which instead may be between 22 and 308 years. We suggest that uncertainty be explicitly stated in fire-history results by bracketing the range of possible population mean FIs. Research and improved methods may narrow the range, but there is no statistical or other method that can eliminate all uncertainty. Longer mean FIs in ponderosa pine forests suggest that (i) surface fire is still important, but less so in maintaining forest structure, and (ii) some dense patches of trees may have occurred in the pre-Euro-American landscape. Creation of low-density forest structure across all parts of ponderosa pine landscapes, particularly in valuable parks and reserves, is not supported by these results.

A landscape approach was used to study fire history and fire behavior in the Douglas-fir forests and foothill vegetation of the Bighorn Canyon National Recreation Area in southcentral Montana. The 3,976 ha study area was divided into 4-ha grid cells, and traditional fire scar analysis and fuel sampling methods were used for data collection in each cell. There have been 15 surface fires during the last 109 years and 10 canopy fires during the last 360 years. The mean fire interval in the forests as a whole, was 7 years for surface fires and 31 years for canopy fires. Using the Weibull function, the recurrent time for fire in a specific grid cell was 212 and 226 years for surface and canopy fires, respectively. The distribution of the probability density function showed that there was a peak of high canopy fire frequency between 150-250 years of stand age. There was no obvious peak period for surface fires in humid ravines, which suggests that surface fires there are not associated with aging. Employing Rothermel's model, a fire behavior model (FIREMDL) was developed and linked it to a geographic information system (GRASS) to simulate flammability of each grid cell under different conditions of fuel moisture and wind velocity. The results suggest that flammability is highly variable because of differences in vegetation and topographic position.

Cross sections from coast redwood trees (Sequoiasempervirens (D.Don.)Endl.) in and near Redwood National Park were dendrochronologically cross-dated and used to develop a fire history from 1714 to 1985. A master chronology for the study area was first developed from old-growth trees and provided dating control for fire-scarred samples. Redwood offers a challenge for dendrochronology owing to partially absent rings (ring wedging) and uniform ring widths (complacency). Cross dating was successful in portions of 12 of 24 fire-scarred trees. Fire events were dated by noting the position of fire scars and other fire-associated ring structures (resin ducts, double latewood, growth releases, and ring separations) in the cross-dated ring series. Using only dates of fire scars, the mean fire interval (MFI) was 9.9 years from the first recorded fire in 1714 to the last in 1962. The MFI was 8.0 years for the best represented (greatest sample depth) presettlement period from 1714 to 1881. Using dates for all fire-associated ring features, the MFI from 1714 to 1962 was 7.0 years and from 1714 to 1881 was 6.0 years. Use of all fire-associated ring characteristics is argued to be a more complete representation of past fire frequency due to possible under-representation of fire-scar records from stump-top samples. Based upon scar positions within annual rings, fires occurred predominately late in the growing season or after growth ceased for the year. The mean fire intervals determined are shorter than those reported in all except one other fire history study from coast redwood and suggest that fire frequency in redwood may have been underestimated in many past studies.

Dendrochronological analysis of fire scars on tree cross sections has been critically important for understanding historical fire regimes and has influenced forest management practices. Despite its value as a tool for understanding historical ecosystems, tree-ring-based fire history reconstruction has rarely been experimentally evaluated. To examine the efficacy of dendrochronological analysis for detecting fire occurrence in oak forests, we analyzed tree cross sections from sites in which prescribed fires had been recently conducted. The first fire in each treatment unit created a scar in at least one sample, but the overall percentage of samples containing scars in fire years was low (12%). We found that scars were created by 10 of the 15 prescribed fires, and the five undetected fires all occurred in sites where fire had occurred the previous year. Notably, several samples contained scars from known fire-free periods. In summary, our data suggest that tree-ring analysis is a generally effective tool for reconstructing historical fire regimes, although the following points of uncertainty were highlighted: (i) consecutive annual burns may not create fire scars and (ii) wounds that are morphologically indistinguishable from fire scars may originate from nonfire sources.

Accurate fire-history data are needed if local management of fire or costly national plans for restoring and managing fire and forest structure are to succeed. Fire-history researchers often use fire scars and the composite fire interval method to reconstruct parameters of past fire regimes, such as the population mean fire interval, but the composite method has serious limitations. We modified an alternative non-composite fire interval method, the individual-tree fire-interval method, to derive a more accurate new method, the all-tree fire-interval method. A stochastic fire-scar generating model to assess the accuracy of the new method and its predecessors was then used. Three factors (scarring ratio, population mean fire interval, and tree age) that affect accuracy were varied in the model runs. More complexity (trees with varied scarring ratio between the first scar and successive scars) also was modelled to test the robustness of the method. The all-tree fire-interval method was shown to greatly improve accuracy and provide unbiased estimates of the population mean fire interval. The method also produced encouraging results when scarring was more complex. The new all-tree fire-interval method will require further research on the rates at which trees are scarred by fire, but this would be generally beneficial to understanding fire history.

Our objective is to report mortality rates for ponderosa pine trees in Oregon ten to eleven years after removing a fire-scarred partial cross-section from them, and five years after an initial survey of post-sampling mortality. We surveyed 138 live trees from which we removed fire-scarred partial crosssections in 1994/95 and 387 similarly sized, unsampled neighbor trees of the same species. These trees were from 78 plots distributed over about 5,000 ha at two sites in northeastern Oregon. The annual mortality rate for sectioned trees from 1994/95 to 2005 was 3.6% compared to 2.1% for the neighbor trees. However, many of the trees that died between 2000 and 2005 were likely killed by two prescribed fires at one of the sites. Excluding all trees in the plots burned by these fires (regardless of whether they died or not), the annual mortality rate for sectioned trees was 1.4% (identical to the rate from 1994/95 to 2000) compared to 1.0% for neighbor trees. During these fires, a greater proportion of sectioned trees died than did catfaced neighbor trees (80% versus 64%) but the difference was not significant.

In the past few decades, wildfires have increased in size and severity in the Southwest and across the western US. These recent trends in fire behavior are a drastic change in arid, ponderosa pine and mixed conifer forests of the Southwest compared with tree-ring records of fire history for the past ~ 400 years. This study presents a late Holocene record (~ 3,000 years) of fire history and related changes in fire regimes with climate variability over annual to multi-decadal time scales. Tree-ring and alluvial-sediment sampling sites were paired in four small, tributary basins located in the western San Juan Mountains of Colorado. In our study sites, tree-ring records show that fire return intervals were longer and fire behavior was more severe on the north-facing slopes with relatively dense mixed conifer stands. Increased fire barriers and steep topography decreased the fire frequency and extent relative to gentle terrain elsewhere in the range and leading to a lack of synchrony among fire years in different parts of the study area. The alluvial-sediment record showed four peaks in high-severity fire activity over the past 3,000 years ranging between 200 - 400 years in length. The timing of peaks coincided with decadal-length drought episodes and were often preceded by multiple decades of above average winter precipitation. The sampling of alluvial-sediment and tree-ring data allowed for site-level comparisons between recent alluvial deposits and specific fire years interpreted from the tree-ring records. We found good correspondence between the type of fire-related sediment deposit (i.e. geomorphic response) in the alluvial record and the extent of mixed and high-severity fire estimated from the tree-ring record, and the correspondence was well-supported by the debris flow probability model results. The two paleofire data tend to represent particular components of the historical fire regime, with alluvial-sediments biased towards infrequent, high-severity events during recent millennia, and the tree-ring record biased toward lower severity fires during recent centuries. The combined analyses of different paleofire proxy types in the same study sites, therefore, can enhance and expand our understanding of fire and climate history beyond what is possible with either proxy alone.

The occurrence of wildfire is influenced by a suite of factors ranging from "top-down" influences (e. g., climate) to "bottom-up" localized influences (e. g., ignitions, fuels, and land use). We carried out the first broad-scale assessment of wildland fire patterns in northern Mexico to assess the relative influence of top-down and bottom-up drivers of fire in a region where frequent fire regimes continued well into the 20th century. Using a network of 67 sites, we assessed (1) fire synchrony and the scales at which synchrony is evident, (2) climate drivers of fire, and (3) asynchrony in fire regime changes. We found high fire synchrony across northern Mexico between 1750 and 2008, with synchrony highest at distances < 400 km. Climate oscillations, especially El Nino-Southern Oscillation, were important drivers of fire synchrony. However, bottom-up factors modified fire occurrence at smaller spatial scales, with variable local influence on the timing of abrupt, unusually long fire-free periods starting between 1887 and 1979 CE. Thirty sites lacked these fire-free periods. In contrast to the neighboring southwestern United States, many ecosystems in northern Mexico maintain frequent fire regimes and intact fire-climate relationships that are useful in understanding climate influences on disturbance across scales of space and time.

Why have so many figures throughout American history proclaimed their life stories when confronted by great political problems? The Claims of Experience provides a new theory for what makes autobiography political throughout the history of the United States and today. Across five chapters, the book examines the democratic crises that encouraged a diverse cast of figures to tell their stories: Benjamin Franklin amid the revolutionary era and its aftermath, Frederick Douglass in the antebellum South and in abolitionist movements, Henry Adams in the Gilded Age and its anxieties of industrial change, Emma Goldman among the first Red Scare and state opposition to radical speech, and Whittaker Chambers amid the second Red Scare that initiated the anticommunist turn of modern conservatism. These authors made a “claim of experience”: a life narrative that offers its audience new community by restoring to readers and author alike from prevailing political authorities the power to remake and make meaning of their lives. Whereas political theorists and activists have often seen autobiography as too individualist or a mere documentary source of evidence, this theory reveals the democratic power that life narratives, both written and spoken, have offered both those on the margins and in the mainstream. When successful, claims of experience redistribute popular authority from unsettled institutions and identities to new democratic visions. This book offers both a method for understanding the politics of life narrative and a call to anticipate claims of experience as they appear today.

‘The deep history of fire’ looks at how fire data can be preserved in nature, such as charcoal deposits and scars on the rings of trees. The history of fire is linked to changes in vegetation and the atmosphere over millennia, like the increasing size of plants and the atmosphere’s changing oxygen content. Wildfires are currently affected by climate in the form of temperature, rainfall, topography, and the length of dry and wet periods. As human intervention increases and the distinction between natural and human-started fires becomes blurred, an understanding of pyrogeography (the study of past, present, and projected wildfire) and pyrodiversity (its varying effects on biodiversity) is increasingly important.

Carcinoma metastatic to the parotid gland is a region-specific disorder. History usually reveals a previous cutaneous squamous cell carcinoma (SCC) or melanoma. Physical examination may show scars of previous operations, current head and neck lesions, associated lymphadenopathy, and altered sensation. Investigations include fiberoptic naso-endoscopy, fine needle aspiration cytology, computed tomography scan, magnetic resonance imaging, and positron emission tomography. Treatment options include surgery (ablative/reconstructive), radiotherapy (indicated for SCC and melanoma), chemotherapy (indicated for SCC), chemo-immunotherapy (may have a role for melanoma). Complications to avoid include (1) wound-related complications (skin flap necrosis and skin flap “button-hole” formation), (2) tumor-related complications (inappropriate surgery due to inadequate preoperative investigation or omitting neck dissection in patients with concomitant neck disease, tumor rupture, and local tumor recurrence), (3) gland-related complications (salivary fistula and sialocele), and (4) nerve-related complications (facial nerve injury, Frey's syndrome or gustatory sweating, and great auricular nerve neuroma).

The windswept wastelands of the Dust Bowl made it clear to many Americans how fragile the human place in nature is. Suddenly, schools across the country wanted to teach conservation, erosion prevention, and wildlife management. Letters piled up on Leopold’s desk, asking his advice. Leopold replied with a list of resources, but his overriding message was that nature was the best teacher. At fifty-one, Leopold had seven graduate students and a full flock of undergraduates. With a blend of affection and awe, they called him “the Professor.” Marie McCabe, the wife of graduate student Robert McCabe, was quite surprised when she first met the Professor. “I had expected him to be a combination of Abe Lincoln and Thomas Jefferson. Here he was, extremely gracious, but of ordinary size and appearance, not at all handsome … showing no sign of being an author and absolute authority on everything.” Game Management 118 had become a campus favorite. Robert S. Ellarson, a Leopold wildlifer, recalled his first meeting: “The class had assembled before the Professor arrived. Soon the clicking of steel-cleated heels signalled his approach. When he arrived and stood before the class, I was impressed by the bold, virile, almost macho appearance of the man. And I was absolutely enthralled by the lecture that followed.” On Saturdays, the class traveled to the arboretum (which was slowly growing toward a natural state) or to various research plots. In the field, Leopold pointed out such elements as animal tracks and rubbings, scat, browsed plants, nests and burrows, gullies and runoff tracks, ground cover and foliage, and rock formations. Then he asked questions, pushing the students to put together the signs they had seen, to draw for themselves a recent and not-so-recent history of the plot of land: . . . Look at the trees in the yard and the soil in the field and tell us whether the original settler carved his farm out of prairie or woods. Did he eat prairie chicken or wild turkey for his Thanksgiving? What plants grew here originally which do not grow here now? Why did they disappear? What did the prairie plants have to do with creating the corn-yielding capacity of this soil? Why does this soil erode now but not then?. . .

This chapter describes the clinical, laboratory, imaging, endoscopic, and histological methods for evaluation of the parotid gland. Diagnostic approaches of parotid gland disorders include clinical evaluation in the form of history-taking (complaints, demographic data, medical profile, medications, and history of the parotid mass itself) and physical examination (intra-oral, extra-oral, and bidigital examination). Laboratory tests entail saliva collection for detection of changes in salivary flow and/or composition. Parotid gland imaging include plain x-ray, sialography, ultrasound (US), computed tomography (CT) scan and CT-sialography, magnetic resonance imaging (MRI), and MR-sialography. Other studies include endoscopy (sialoendoscopy) and parotid biopsy (core-biopsy, frozen-section) and fine needle aspiration cytology (FNAC).

This chapter explains how the Cold War, and especially the Red Scare, shaped Reddick’s actions while serving as the chief librarian of Atlanta University from 1948 to 1955, where he worked with Clarence Bacote, Hylan G. Lewis, and Benjamin Mays. Reddick’s refusal to condone America’s militarist foreign policy and its persecution of leftists at home contributed to his becoming the subject of a Federal Bureau of Investigation probe as well as a target of white Southern politicians, such as Herman Talmadge, who were committed to halting the burgeoning civil rights movement. Reddick nevertheless continued to his cultivate Pan-African ties, particularly by coordinating a monthlong visit by Nigeria’s Nnamdi Azikiwe and by co-authoring with W. Sherman Savage a history of his fraternity, Phi Beta Sigma. Reddick also promoted desegregation as a two-way street while helping prepare for a post-Brown v. Board of Education world. He likewise participated in local politics and the protracted struggles of the Association for the Study of Negro Life and History in the wake of Carter G. Woodson’s death. Finally, he left in Atlanta in 1955 after being fired by Atlanta University president Rufus Clement.

<em>Abstract</em>.—Shoal Bass <em>Micropterus cataractae</em> is a black bass species endemic to limited sections within the Apalachicola, Chattahoochee, and Flint River systems in Alabama, Florida, and Georgia. The restricted range of this species has resulted in a paucity of life history information, especially regarding reproductive ecology and nesting habitat requirements. The objectives of this study were to describe and document Shoal Bass nesting, associated habitat, and nest-specific environmental variables in the Chipola River, Florida, a tributary of the Apalachicola River. Through the use of radiotelemetry and visual observation, 89 nests were located and used to quantify macrohabitat selection or use. Shoal Bass nesting was documented from mid-April to mid-May during 2011 and 2012. Average nest depth was 102 cm (SE = 3.2), and the average water temperature was 22.6°C (SE = 0.2). Available macrohabitat for the Chipola River was quantified using side-scan sonar and classified into four substrate types: bedrock, boulder, rocky fine, and sand-gravel. More than 80% of all nests were in either boulder (17% availability) or rocky fine (27% availability) macrohabitats. Determining Shoal Bass nesting habitats and associated parameters will provide managers with the knowledge needed for future habitat protection and enhancement in the Chipola River, Florida.

Chemical peels, mechanical abrasion, and more recently laser and electrosurgical devices are used to resurface eyelid and facial skin. The common feature in these techniques is the denaturation or removal of the skin surface. These techniques typically help to hide skin changes related to sun exposure and aging by evening the skin tone, decreasing dyschromia, and diminishing wrinkles. These techniques all require careful case selection and patient preparation with appropriate treatment and postoperative care. Recent interest has focused on less invasive therapy with techniques that leave the epithelium largely intact, shortening healing time and reducing the risk of complications. Aging and sun damage induce a number of changes in skin, including wrinkling, the development of muscle- or gravity-related folds, irregular pigment or dyschromia, and the growth of benign and malignant skin lesions. Scars from acne, trauma, or surgery can also be indications for skin resurfacing. Potential benefit in all of these techniques must be balanced against risks and expected healing time. A medical history must be obtained, looking for a history of immune dysfunction, prior acne, or a history of herpes simplex outbreaks. Prior treatment with radiation or isotretinoin (Accutane) may diminish the pilosebaceous units required for healing. Acne rosacea and cutaneous telangiectasia may be aggravated by skin resurfacing. Cutaneous history must focus on scarring tendencies such as keloid formation, skin type, and ancestry. In particular, one must determine the patient’s skin type, most commonly by assigning a Fitzpatrick’s skin type. Patients with skin type III require careful topical preparation for skin resurfacing treatment in most cases, and patients with skin type IV or higher are more prone to scarring and pigment issues and are not treated with medium depth to deep skin resurfacing techniques by most clinicians. Wrinkles may be graded by the Glogau classification scheme. This scale from “fine wrinkles” (type 1) to “only wrinkles” (type IV) will help to define the amount and type of treatment needed. These loose recommendations will generally hold true in determining effective therapy. The deeper and more invasive the treatment, the more important the role of skin preparation and prophylaxis.

In almost everybody’s natural lifetime, the sea is one of the great unchanging certainties of life. There is land; there is sea; and in between is that magical place, the seaside, which is sometimes knocked about a bit by the waves, but always manages to recover for that next idyllic summer. There are, one remembers, those faintly disquieting legends, about a remarkably well-organized and ecologically aware person called Noah, and about a Deluge. But these, of course, should not be taken seriously. They were a jumpy and superstitious lot, our ancestors, always prone to making up scary stories. It was a good way to keep the children in order. With a longer perspective, things seem a little different. Take any one location on the globe, for instance. Track it over millions of years. At that one location, there may be a change from deep ocean, to shallow sea, to a shoreline, and thence to terrestrial swamps and flood plains. And then, perhaps, to the absence of evidence, a horizon of absolutely no thickness at all within a succession of rock strata, in which a million years or a hundred million years—or more—may be missing, entirely unrecorded. It is that phenomenon called an unconformity, all that is left of the history of a terrestrial landscape pushed up into the erosional realm. On that eroding landscape, there may have been episodes of battle, murder, and sudden death among armoured saurians, of fire, flood, and storm, and of the humdrum day-to-day life of the vast vegetarian dinosaurs, chewing through their daily hundredweights of plants. Of this, no trace can persist. Only when that landscape is plunged again towards sea level, and begins to be silted up, can a tangible geological record resume. The Earth’s crust, as we have seen, is malleable, can be pushed downwards or thrust upwards by the forces that drive the continents across the face of the globe. Many of the sea level changes that can be read in the strata of the archives are of this sort, and mark purely local ups and downs of individual sections of crust, with no evidence that global sea level was anything other than constant.

Laser Additive Manufacturing (LAM) is one of the greener routes for fabrication of Inconel 718 (IN718) components. In the present work, Taguchi L9 array based optimization is performed using grey relational analysis to optimize the process parameters for the fabrication of thin walled structures using a 2 kW fibre laser based additive manufacturing system. Within the framework of the experimental conditions of the study, the LAM processing parameters, i.e., laser power, scan speed and powder feed rate, are optimized for minimum width and maximum height. The optimized parameters are used for the deposition of multi-layered walls and it is subjected to heat treatment at 1000 °C for duration of one-hour, followed by water quenching. Comprehensive investigations on microstructural and mechanical behaviour using optical microscopy (OM), X-ray diffraction (XRD) analysis, micro-hardness and automated ball indentation (ABI) are carried out. Microstructure examinations of LAM deposits of IN718 reveal intermixed dendritic and cellular structures. However, homogenization in microstructure is observed through heat treatment resulting in reduced micro-hardness. It is also observed that there is considerable increase in the crystallite size of the deposits after heat treatment. This study opens a new route for fabrication of thin walled structures using LAM with modified properties by erasing the thermal history through heat treatment.

Measures exist to adjust tailpipe NOx emissions to assigned values, for example cooled exhaust gas recirculation (EGR) or a SCR catalyst in conjunction with urea. The situation is quite different with soot when use of a trap is not feasible for reasons of cost, space requirements and maintenance. Due to the highly complex soot formation and oxidation process, soot emissions can’t be targeted as easily as NOX. So how can soot be kept within the limits? In principle, soot can be controlled by allocating sufficient oxygen and establishing good mixing conditions with vaporized fuel. The most effective measures target the injection system, e.g. increasing injection pressure, applying multiple injections, optimizing nozzle geometry. To investigate the impact of very high injection pressure on soot, an advanced injection system with rail pressure capability up to 3000 bar and a Bosch injector was installed at the Large Engines Competence Center (LEC) in Graz. Full load and part load operating points at constant speed and in accordance with the propeller law were investigated at the test bed to quantify the impact of high injection pressure on soot emissions. Test runs were conducted with both SCR and EGR while varying injection timing and air-fuel ratios. Use of a statistical method, Design of Experiments (DOE), helped reduce the number of tests. Optical investigations of the spray and combustion were conducted. The goal was to obtain soot concentration history traces with the two color method in order to better understand how soot originates and to be able to calibrate 3D CFD FIRE spray models for use with injection pressures of up to 3000 bar. Very low soot emissions can be achieved using high pressure injection, even when EGR is applied. DOE results provide a clear picture of the relationships between the parameters and can be used to optimize set values for the whole speed and load range. A reliable spray break up model can be used in further 3D CFD simulation to investigate how to reduce soot emissions.

Introduction: Sertoli-Leydig cell tumor (SLCT) is a rare ovarian tumor, Constitute less than 0.5% of ovarian tumors. Most tumors are unilateral, confined to the ovaries. They are seen during the second and third decades of life. They are characterized by the presence of testicular structures that produce androgens. Patients have symptoms of virilization (depending on the quantity of androgen). Case Report: A 42-year-old woman presented Amenorrhea for 14 months. Change in her voice for 1 year and Excessive hair growth on her face, chest, and limbs for the last 2 months. She complained of vague abdominal discomfort. No history of anorexia, weight loss, increased libido. Her medical and family history was unremarkable. On examination - Hirsutism and clitoromegaly. Lump of size 10x8 cm palpable in left iliac fossa. Vaginal examination revealed a firm and mobile cystic mass in the right adnexa. An ultrasound examination of the pelvis showed a 17x 13x 9-cm heterogeneous solid cystic mass replacing the left ovary. The right ovary and the uterus were normal. CECT Scan Abdomen-Large heterogenous encapsulated solid soft tissue mass lesions containing areas of calcification arising from left ovary of size 17x13x10.6cm causing displacement of urinary bladder and surrounding bowel loops. Serum testosterone level -2 ng/mL (normal, 0.2–1.2 ng/mL); (DHEAS), CA 125, and alpha fetoprotein (AFP) -normal. On Laparotmy-Large mass of size 17 X 13 cm arising from left adnexa. Uterus and right ovary grossly normal. Total Abdominal hysterectomy, B/L Salpingo-opherectomy and infracolic omentectomy was done. Peritoneal washing were sent for cytologic examination for malignant cells. No liver metastasis. The post operative period was uneventful. Histopathology revealed- confirmed it be Sertoli Leydig cell tumor. 3month follow up – resolution of her virilization symptoms. No increase of her hirsutism. Repeat testosterone levels - within normal range. Conclusion: Only few cases of SLCT have been reported till date Prognosis depends on extent of disease, stage of disease, tumour differentiation, grade. The treatment should be individualized according to the location, state of spread and the patient’s condition.

Purpose: To evaluate the role of 18F-FDG PET with contrast enhanced CT (PET-CECT) in early detection of recurrence in follow up patients of carcinoma cervix. Methods: Patients with histopathologically proven carcinoma cervix who underwent chemotherapy, radiotherapy and/or surgery and on follow up were recruited in the study. Fifty-two patients underwent 18F-FDG PET-CECT for detection of recurrence. The median age was 51.5 (average = 53.4) years. PET-CECT studies were evaluated and analyzed separately by an experienced nuclear medicine physician and a radiologist independently. The physicians were blinded for the patient history. PET-CECT results were validated with histopathological correlation, conventional radiologic imaging/follow up PET-CECT study and clinical follow up. Results: Out of 52 patients, 34 patients were reported as positive for recurrence, 17 of these were having active local recurrence and 31 patients had regional lymph nodal metastases, 14 patients had distant metastases (out of them 6 patients had distant lymph node metastases, 6 had pulmonary metastases, 4 had skeletal metastases and two had liver metastases). Remaining 18 patients were reported as negative for recurrence. The lung was the most common site for distant metastasis. Patient were then further evaluated based on histopathological correlation, conventional radiologic imaging and follow up PET-CECT scan and five were found to be false positive and one patient was identified as false negative. The sensitivity, specificity, positive and negative predictive value were derived to be 96.7%, 77.3%, 85.3% and 94.4%, respectively. Accuracy was calculated to be 88.5%. Conclusions: 18F-FDG PET-CECT is a very useful non-invasive modality for the early detection of recurrence and metastatic workup in patients with carcinoma cervix with a very high sensitivity and negative predictive value. It is also useful in targeting biopsy sites in suspected cases of recurrence.

Introduction: Immature teratoma represents 3% of all teratomas, 1 % of all ovarian cancers and 20% of malignant ovarian germ cell tumors. It is found either in pure form or as a component of a mixed germ cell tumor. It occurs essentially during the first two decades of life. According to WHO, immature teratoma is defined as a teratoma containing a variable amount of immature embryonal type neuroectodermal tissue Case: We present here a report of 23 years old unmarried female who presented with complaint of abdominal pain since 1 month and her CT scan done outside, showed fibroid uterus. She had history of typhoid fever 1 month back for which USG was done which suggested large uterine fibroid. On examination she was hemodynamically stable. On abdominal examination a non-tender supra-pubic mass of 24 weeks size with firm consistency, irregular margin was felt. On investigation CA 125 was 64.90 IU/L, LD- 223, beta HCG- 1.14. On MRI a large abdomino-pelvic lesion, likely left adnexal lesion with multiple cystic areas, with hemorrhage, with ascites and enlarged retroperitoneal lymph nodes with omental infiltration suggestive of a possibility of malignant germ cell tumor. In view of large ovarian tumor, possibly malignant decision for staging laparotomy was taken. Intra-operatively a large irregular vascular solid mass of 20 x 20 cms with bosselated appearance with few cystic lesions over it was seen, arising from left ovary and was sent for frozen section which reported malignant mature teratoma with components of immature teratoma. She underwent laparotomy with left salpingo-oophorectomy with right ovarian biopsy, omentectomy, appendectomy with B/L pelvic lymphadenectomy. Histopathology was suggestive of grade III immature teratoma. In view of grade III immature teratoma, she received chemotherapy (BEP regimen) post-operatively and is currently under follow up. Conclusion: This case reflects the importance of early diagnosis in cases of pelvic masses in young females. Fertility preservation should be considered in young women with germ cell tumors. Patients with grade II or III tumors or a mere advanced stage disease should be treated with adjuvant chemotherapy (BEP) in addition to surgery.

The main recommendations of the panel report can be summarised under five key headings:  Building the Scottish Bronze Age: Narratives should be developed to account for the regional and chronological trends and diversity within Scotland at this time. A chronology Bronze Age Scotland: ScARF Panel Report iv based upon Scottish as well as external evidence, combining absolute dating (and the statistical modelling thereof) with re-examined typologies based on a variety of sources – material cultural, funerary, settlement, and environmental evidence – is required to construct a robust and up to date framework for advancing research.  Bronze Age people: How society was structured and demographic questions need to be imaginatively addressed including the degree of mobility (both short and long-distance communication), hierarchy, and the nature of the ‘family’ and the ‘individual’. A range of data and methodologies need to be employed in answering these questions, including harnessing experimental archaeology systematically to inform archaeologists of the practicalities of daily life, work and craft practices.  Environmental evidence and climate impact: The opportunity to study the effects of climatic and environmental change on past society is an important feature of this period, as both palaeoenvironmental and archaeological data can be of suitable chronological and spatial resolution to be compared. Palaeoenvironmental work should be more effectively integrated within Bronze Age research, and inter-disciplinary approaches promoted at all stages of research and project design. This should be a two-way process, with environmental science contributing to interpretation of prehistoric societies, and in turn, the value of archaeological data to broader palaeoenvironmental debates emphasised. Through effective collaboration questions such as the nature of settlement and land-use and how people coped with environmental and climate change can be addressed.  Artefacts in Context: The Scottish Chalcolithic and Bronze Age provide good evidence for resource exploitation and the use, manufacture and development of technology, with particularly rich evidence for manufacture. Research into these topics requires the application of innovative approaches in combination. This could include biographical approaches to artefacts or places, ethnographic perspectives, and scientific analysis of artefact composition. In order to achieve this there is a need for data collation, robust and sustainable databases and a review of the categories of data.  Wider Worlds: Research into the Scottish Bronze Age has a considerable amount to offer other European pasts, with a rich archaeological data set that includes intact settlement deposits, burials and metalwork of every stage of development that has been the subject of a long history of study. Research should operate over different scales of analysis, tracing connections and developments from the local and regional, to the international context. In this way, Scottish Bronze Age studies can contribute to broader questions relating both to the Bronze Age and to human society in general.

The main recommendations of the Panel report can be summarised as follows: The Overall Picture: more needs to be understood about the process of acculturation of indigenous communities; about the Atlantic, Breton strand of Neolithisation; about the ‘how and why’ of the spread of Grooved Ware use and its associated practices and traditions; and about reactions to Continental Beaker novelties which appeared from the 25th century. The Detailed Picture: Our understanding of developments in different parts of Scotland is very uneven, with Shetland and the north-west mainland being in particular need of targeted research. Also, here and elsewhere in Scotland, the chronology of developments needs to be clarified, especially as regards developments in the Hebrides. Lifeways and Lifestyles: Research needs to be directed towards filling the substantial gaps in our understanding of: i) subsistence strategies; ii) landscape use (including issues of population size and distribution); iii) environmental change and its consequences – and in particular issues of sea level rise, peat formation and woodland regeneration; and iv) the nature and organisation of the places where people lived; and to track changes over time in all of these. Material Culture and Use of Resources: In addition to fine-tuning our characterisation of material culture and resource use (and its changes over the course of the Neolithic), we need to apply a wider range of analytical approaches in order to discover more about manufacture and use.Some basic questions still need to be addressed (e.g. the chronology of felsite use in Shetland; what kind of pottery was in use, c 3000–2500, in areas where Grooved Ware was not used, etc.) and are outlined in the relevant section of the document. Our knowledge of organic artefacts is very limited, so research in waterlogged contexts is desirable. Identity, Society, Belief Systems: Basic questions about the organisation of society need to be addressed: are we dealing with communities that started out as egalitarian, but (in some regions) became socially differentiated? Can we identify acculturated indigenous people? How much mobility, and what kind of mobility, was there at different times during the Neolithic? And our chronology of certain monument types and key sites (including the Ring of Brodgar, despite its recent excavation) requires to be clarified, especially since we now know that certain types of monument (including Clava cairns) were not built during the Neolithic. The way in which certain types of site (e.g. large palisaded enclosures) were used remains to be clarified. Research and methodological issues: There is still much ignorance of the results of past and current research, so more effective means of dissemination are required. Basic inventory information (e.g. the Scottish Human Remains Database) needs to be compiled, and Canmore and museum database information needs to be updated and expanded – and, where not already available online, placed online, preferably with a Scottish Neolithic e-hub that directs the enquirer to all the available sources of information. The Historic Scotland on-line radiocarbon date inventory needs to be resurrected and kept up to date. Under-used resources, including the rich aerial photography archive in the NMRS, need to have their potential fully exploited. Multi-disciplinary, collaborative research (and the application of GIS modelling to spatial data in order to process the results) is vital if we are to escape from the current ‘silo’ approach and address key research questions from a range of perspectives; and awareness of relevant research outside Scotland is essential if we are to avoid reinventing the wheel. Our perspective needs to encompass multi-scale approaches, so that ScARF Neolithic Panel Report iv developments within Scotland can be understood at a local, regional and wider level. Most importantly, the right questions need to be framed, and the right research strategies need to be developed, in order to extract the maximum amount of information about the Scottish Neolithic.

Climate and hydrology are major drivers of ecosystems. They dramatically shape ecosystem structure and function, particularly in arid and semi-arid ecosystems. Understanding changes in climate, groundwater, and water quality and quantity is central to assessing the condition of park biota and key cultural resources. The Sonoran Desert Network collects data on climate, groundwater, and surface water at 11 National Park Service units in southern Arizona and New Mexico. This report provides an integrated look at climate, groundwater, and springs conditions at Chiricahua National Monument (NM), Coronado National Memorial (NMem), and Fort Bowie National Historic Site (NHS) during water year (WY) 2019 (October 2018–September 2019). Overall annual precipitation at Chiricahua NM and Coronado NMem in WY2019 was approximately the same as the normals for 1981–2010. (The weather station at Fort Bowie NHS had missing values on 275 days, so data were not presented for that park.) Fall and winter rains were greater than normal. The monsoon season was generally weaker than normal, but storm events related to Hurricane Lorena led to increased late-season rain in September. Mean monthly maximum temperatures were generally cooler than normal at Chiricahua, whereas mean monthly minimum temperatures were warmer than normal. Temperatures at Coronado were more variable relative to normal. The reconnaissance drought index (RDI) indicated that Chiricahua NM was slightly wetter than normal. (The WY2019 RDI could not be calculated for Coronado NMem due to missing data.) The five-year moving mean of annual precipitation showed both park units were experiencing a minor multi-year precipitation deficit relative to the 39-year average. Mean groundwater levels in WY2019 increased at Fort Bowie NHS, and at two of three wells monitored at Chiricahua NM, compared to WY2018. Levels in the third well at Chiricahua slightly decreased. By contrast, water levels declined in five of six wells at Coronado NMem over the same period, with the sixth well showing a slight increase over WY2018. Over the monitoring record (2007–present), groundwater levels at Chiricahua have been fairly stable, with seasonal variability likely caused by transpiration losses and recharge from runoff events in Bonita Creek. At Fort Bowie’s WSW-2, mean groundwater level was also relatively stable from 2004 to 2019, excluding temporary drops due to routine pumping. At Coronado, four of the six wells demonstrated increases (+0.30 to 11.65 ft) in water level compared to the earliest available measurements. Only WSW-2 and Baumkirchner #3 have shown net declines (-17.31 and -3.80 feet, respectively) at that park. Springs were monitored at nine sites in WY2019 (four sites at Chiricahua NM; three at Coronado NMem, and two at Fort Bowie NHS). Most springs had relatively few indications of anthropogenic or natural disturbance. Anthropogenic disturbance included modifications to flow, such as dams, berms, or spring boxes. Examples of natural disturbance included game trails, scat, or evidence of flooding. Crews observed 0–6 facultative/obligate wetland plant taxa and 0–3 invasive non-native species at each spring. Across the springs, crews observed six non-native plant species: common mullein (Verbascum thapsus), spiny sowthistle (Sonchus asper), common sowthistle (Sonchus oleraceus), Lehmann lovegrass (Eragrostis lehmanniana), rabbitsfoot grass (Polypogon monspeliensis), and red brome (Bromus rubens). Baseline data on water quality and water chemistry were collected at all nine sites. It is likely that that all nine springs had surface water for at least some part of WY2019, though temperature sensors failed at two sites. The seven sites with continuous sensor data had water present for most of the year. Discharge was measured at eight sites and ranged from < 1 L/minute to 16.5 L/minute.

Background Lung cancer is the number one cause of cancer death worldwide.(1) It is the fifth most commonly diagnosed cancer in Australia (12,741 cases diagnosed in 2018) and the leading cause of cancer death.(2) The number of years of potential life lost to lung cancer in Australia is estimated to be 58,450, similar to that of colorectal and breast cancer combined.(3) While tobacco control strategies are most effective for disease prevention in the general population, early detection via low dose computed tomography (LDCT) screening in high-risk populations is a viable option for detecting asymptomatic disease in current (13%) and former (24%) Australian smokers.(4) The purpose of this Evidence Check review is to identify and analyse existing and emerging evidence for LDCT lung cancer screening in high-risk individuals to guide future program and policy planning. Evidence Check questions This review aimed to address the following questions: 1. What is the evidence for the effectiveness of lung cancer screening for higher-risk individuals? 2. What is the evidence of potential harms from lung cancer screening for higher-risk individuals? 3. What are the main components of recent major lung cancer screening programs or trials? 4. What is the cost-effectiveness of lung cancer screening programs (include studies of cost–utility)? Summary of methods The authors searched the peer-reviewed literature across three databases (MEDLINE, PsycINFO and Embase) for existing systematic reviews and original studies published between 1 January 2009 and 8 August 2019. Fifteen systematic reviews (of which 8 were contemporary) and 64 original publications met the inclusion criteria set across the four questions. Key findings Question 1: What is the evidence for the effectiveness of lung cancer screening for higher-risk individuals? There is sufficient evidence from systematic reviews and meta-analyses of combined (pooled) data from screening trials (of high-risk individuals) to indicate that LDCT examination is clinically effective in reducing lung cancer mortality. In 2011, the landmark National Lung Cancer Screening Trial (NLST, a large-scale randomised controlled trial [RCT] conducted in the US) reported a 20% (95% CI 6.8% – 26.7%; P=0.004) relative reduction in mortality among long-term heavy smokers over three rounds of annual screening. High-risk eligibility criteria was defined as people aged 55–74 years with a smoking history of ≥30 pack-years (years in which a smoker has consumed 20-plus cigarettes each day) and, for former smokers, ≥30 pack-years and have quit within the past 15 years.(5) All-cause mortality was reduced by 6.7% (95% CI, 1.2% – 13.6%; P=0.02). Initial data from the second landmark RCT, the NEderlands-Leuvens Longkanker Screenings ONderzoek (known as the NELSON trial), have found an even greater reduction of 26% (95% CI, 9% – 41%) in lung cancer mortality, with full trial results yet to be published.(6, 7) Pooled analyses, including several smaller-scale European LDCT screening trials insufficiently powered in their own right, collectively demonstrate a statistically significant reduction in lung cancer mortality (RR 0.82, 95% CI 0.73–0.91).(8) Despite the reduction in all-cause mortality found in the NLST, pooled analyses of seven trials found no statistically significant difference in all-cause mortality (RR 0.95, 95% CI 0.90–1.00).(8) However, cancer-specific mortality is currently the most relevant outcome in cancer screening trials. These seven trials demonstrated a significantly greater proportion of early stage cancers in LDCT groups compared with controls (RR 2.08, 95% CI 1.43–3.03). Thus, when considering results across mortality outcomes and early stage cancers diagnosed, LDCT screening is considered to be clinically effective. Question 2: What is the evidence of potential harms from lung cancer screening for higher-risk individuals? The harms of LDCT lung cancer screening include false positive tests and the consequences of unnecessary invasive follow-up procedures for conditions that are eventually diagnosed as benign. While LDCT screening leads to an increased frequency of invasive procedures, it does not result in greater mortality soon after an invasive procedure (in trial settings when compared with the control arm).(8) Overdiagnosis, exposure to radiation, psychological distress and an impact on quality of life are other known harms. Systematic review evidence indicates the benefits of LDCT screening are likely to outweigh the harms. The potential harms are likely to be reduced as refinements are made to LDCT screening protocols through: i) the application of risk predication models (e.g. the PLCOm2012), which enable a more accurate selection of the high-risk population through the use of specific criteria (beyond age and smoking history); ii) the use of nodule management algorithms (e.g. Lung-RADS, PanCan), which assist in the diagnostic evaluation of screen-detected nodules and cancers (e.g. more precise volumetric assessment of nodules); and, iii) more judicious selection of patients for invasive procedures. Recent evidence suggests a positive LDCT result may transiently increase psychological distress but does not have long-term adverse effects on psychological distress or health-related quality of life (HRQoL). With regards to smoking cessation, there is no evidence to suggest screening participation invokes a false sense of assurance in smokers, nor a reduction in motivation to quit. The NELSON and Danish trials found no difference in smoking cessation rates between LDCT screening and control groups. Higher net cessation rates, compared with general population, suggest those who participate in screening trials may already be motivated to quit. Question 3: What are the main components of recent major lung cancer screening programs or trials? There are no systematic reviews that capture the main components of recent major lung cancer screening trials and programs. We extracted evidence from original studies and clinical guidance documents and organised this into key groups to form a concise set of components for potential implementation of a national lung cancer screening program in Australia: 1. Identifying the high-risk population: recruitment, eligibility, selection and referral 2. Educating the public, people at high risk and healthcare providers; this includes creating awareness of lung cancer, the benefits and harms of LDCT screening, and shared decision-making 3. Components necessary for health services to deliver a screening program: a. Planning phase: e.g. human resources to coordinate the program, electronic data systems that integrate medical records information and link to an established national registry b. Implementation phase: e.g. human and technological resources required to conduct LDCT examinations, interpretation of reports and communication of results to participants c. Monitoring and evaluation phase: e.g. monitoring outcomes across patients, radiological reporting, compliance with established standards and a quality assurance program 4. Data reporting and research, e.g. audit and feedback to multidisciplinary teams, reporting outcomes to enhance international research into LDCT screening 5. Incorporation of smoking cessation interventions, e.g. specific programs designed for LDCT screening or referral to existing community or hospital-based services that deliver cessation interventions. Most original studies are single-institution evaluations that contain descriptive data about the processes required to establish and implement a high-risk population-based screening program. Across all studies there is a consistent message as to the challenges and complexities of establishing LDCT screening programs to attract people at high risk who will receive the greatest benefits from participation. With regards to smoking cessation, evidence from one systematic review indicates the optimal strategy for incorporating smoking cessation interventions into a LDCT screening program is unclear. There is widespread agreement that LDCT screening attendance presents a ‘teachable moment’ for cessation advice, especially among those people who receive a positive scan result. Smoking cessation is an area of significant research investment; for instance, eight US-based clinical trials are now underway that aim to address how best to design and deliver cessation programs within large-scale LDCT screening programs.(9) Question 4: What is the cost-effectiveness of lung cancer screening programs (include studies of cost–utility)? Assessing the value or cost-effectiveness of LDCT screening involves a complex interplay of factors including data on effectiveness and costs, and institutional context. A key input is data about the effectiveness of potential and current screening programs with respect to case detection, and the likely outcomes of treating those cases sooner (in the presence of LDCT screening) as opposed to later (in the absence of LDCT screening). Evidence about the cost-effectiveness of LDCT screening programs has been summarised in two systematic reviews. We identified a further 13 studies—five modelling studies, one discrete choice experiment and seven articles—that used a variety of methods to assess cost-effectiveness. Three modelling studies indicated LDCT screening was cost-effective in the settings of the US and Europe. Two studies—one from Australia and one from New Zealand—reported LDCT screening would not be cost-effective using NLST-like protocols. We anticipate that, following the full publication of the NELSON trial, cost-effectiveness studies will likely be updated with new data that reduce uncertainty about factors that influence modelling outcomes, including the findings of indeterminate nodules. Gaps in the evidence There is a large and accessible body of evidence as to the effectiveness (Q1) and harms (Q2) of LDCT screening for lung cancer. Nevertheless, there are significant gaps in the evidence about the program components that are required to implement an effective LDCT screening program (Q3). Questions about LDCT screening acceptability and feasibility were not explicitly included in the scope. However, as the evidence is based primarily on US programs and UK pilot studies, the relevance to the local setting requires careful consideration. The Queensland Lung Cancer Screening Study provides feasibility data about clinical aspects of LDCT screening but little about program design. The International Lung Screening Trial is still in the recruitment phase and findings are not yet available for inclusion in this Evidence Check. The Australian Population Based Screening Framework was developed to “inform decision-makers on the key issues to be considered when assessing potential screening programs in Australia”.(10) As the Framework is specific to population-based, rather than high-risk, screening programs, there is a lack of clarity about transferability of criteria. However, the Framework criteria do stipulate that a screening program must be acceptable to “important subgroups such as target participants who are from culturally and linguistically diverse backgrounds, Aboriginal and Torres Strait Islander people, people from disadvantaged groups and people with a disability”.(10) An extensive search of the literature highlighted that there is very little information about the acceptability of LDCT screening to these population groups in Australia. Yet they are part of the high-risk population.(10) There are also considerable gaps in the evidence about the cost-effectiveness of LDCT screening in different settings, including Australia. The evidence base in this area is rapidly evolving and is likely to include new data from the NELSON trial and incorporate data about the costs of targeted- and immuno-therapies as these treatments become more widely available in Australia.