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The first issue of I Quaternary Research: An Interdisciplinary Journal i was published in September 1970, making it the first international journal dedicated to the study of the Quaternary by scientists of all disciplines. They document the significant advances in our understanding of the Quaternary and the causes and effects of the climate and sea-level changes that characterize this period of earth history. The graphs show the percentage of pollen originating within specified distances of the basin margin: the diagrams form a series with the graphs for the lightest pollen type at the top. [Extracted from the article]

Mountain glaciers at ∼26–19 ka, during the global Last Glacial Maximum near the end of the last 10 5 yr glacial cycle, are commonly considered on the basis of dating and field mapping in several well-studied areas to have been the largest of the late Quaternary and to have advanced synchronously from region to region. However, a numerical sensitivity model (Rupper and Roe, 2008) predicts that the fraction of ablation due to melting varies across Central Asia in proportion to the annual precipitation. The equilibrium-line altitude of glaciers across this region likely varies accordingly: in high altitude, cold and arid regions sublimation can ablate most of the ice, whereas glaciers fed by high precipitation cannot ablate completely due to sublimation alone, but extend downhill until higher temperatures there cause them to melt. We have conducted field studies and 10 Be dating at five glaciated sites along a precipitation gradient in Mongolia to test the Rupper/Roe model. The sites are located in nearby 1.875 × 1.875° cells of the Rupper/Roe model, each with a different melt fraction, in this little-studied region. The modern environment of the sites ranges from dry subhumid in the north (47.7° N) to arid in the south (45° N). Our findings show that the maximum local advances in the dry subhumid conditions predated the global Last Glacial Maximum and were likely from MIS 3. However, we also found that at ∼8–7 ka a cirque glacier in one mountain range of the arid Gobi desert grew to a magnitude comparable to that of the local maximum extent. This Holocene maximum occurred during a regional pluvial period thousands of years after the retreat of the Pleistocene glaciers globally. This asynchronous behavior is not predicted by the prevailing and generally correct presumption that glacier advances are dominantly driven by temperature, although precipitation also plays a role. Our findings are consistent with and support the Rupper/Roe model, which calls for glaciation in arid conditions only at high altitudes of sub-freezing temperatures, where the melt fraction in ablation is low. We expect a heterogeneous pattern of glacial responses to a changing modern climate in cold arid regions; an individual glacier advance should not be necessarily interpreted as evidence of cooling climate. [ABSTRACT FROM AUTHOR]

Some of the largest cataclysmic floods of the Quaternary followed multiple breaches of glaciers damming the headwaters of the Maly Yenisei river in southern Siberia. The shorelines of the impounded lake in Darhad basin suggest at least four depths of 290, 175, 145, and 65 m. Fossil evidence, together with previous 14C and luminescence dating, indicates the existence of a deep lake during MIS 3; the eroded character of the highest shoreline suggests that the deepest lake was older. 10Be dating of moraines in the surrounding mountains has documented major glacial advances during MIS 2, although no published direct dating has confirmed a highstand of the lake then. To address this problem, we extracted lake sediments from a 92.6 m deep borehole, sampled beach sands from the nearby basin edge, and dated them both using luminescence methods. We also dated, with 10Be, the eroded remnants of the end moraine deposited by the last glacier that dammed Darhad basin, as well as other moraines in the mountains surrounding the basin. These numerical ages confirm that a deep lake existed in Darhad basin at ~20 ka and that a large glacier crossed the Maly Yenisei and dammed Darhad basin at ~21 ka. The deep lake persisted episodically until ~14 ka. The 10Be dating in the surrounding mountains shows that the MIS 2 glaciers subsequently retreated but stalled or re-advanced at ~12, 10, and 1.5 ka. 10Be dating from the central massif of Mongolia is consistent with this chronology and confirms that MIS 3 equilibrium-line altitudes were slightly (~75 m) lower or approximately the same as those of the MIS 2. The temporal and spatial patterns of glacial advances in southern Siberia and central Mongolia coincided with those of glacial advances in similar climate conditions of the Altai mountains. [ABSTRACT FROM AUTHOR]

The Yenisei, the largest river flowing to the Arctic Ocean, repeatedly hosted cataclysmic floods during the Pleistocene. The largest of the known floods likely originated from palaeolakes in northern Mongolia, at the headwaters of the Little, or Maly, Yenisei. These ancient floods are among the greatest known globally. They left giant gravel dunes and wide abandoned channels in the Kyzyl basin, and high terraces in the gorges upstream. However, few detailed field studies of the flood deposits and no measurements of their ages have been made thus far. The largest palaeolakes were impounded during major glaciations by outlet glaciers from the East Sayan ice field in southern Siberia. The shorelines suggest four distinct palaeolake depths of 290, 175, 145, and 65 m. The timing and location of the glacier impounding the deepest lakes are uncertain but at its maximum, the Tengis outlet glacier was likely capable of impounding the 175 m lake. The dating of glacial deposits in and around the basin reveals that the maximum late Pleistocene glaciers were during Marine Oxygen Isotope Stage (MIS) 3. The ages for deep-lake sediments exposed in the basin behind the dam’s location support this finding. During MIS 2 the Tengis glacier was large enough to impound at least the 145 m lake. However, the existence of a deep MIS 2 palaeolake in the basin has been challenged, because no evidence has been published of MIS 2 lake sediments from the cutbank outcrops and deep drilling cores. Additionally, the end moraines of the Tengis glacier, separated from the deeply eroded lateral moraines by the Maly Yenisei, remain undated; therefore it is uncertain exactly when this glacier crossed the river. This review is part I of a two-part article; Part II presents new age data to constrain the ages of the glacial dam. [ABSTRACT FROM PUBLISHER]

Large-scale engineering projects such as mines and dams cause ecological damage that can persist after construction is complete. The Qinghai–Tibet Railway (QTR) from Golmud to Lhasa was constructed entirely during the Landsat era and began operating in 2006. Therefore, it presents an opportunity for determining both the extent of ecological damage and the time required for some level of natural restoration after a major construction project. We have studied the effect of the QTR construction on vegetation abundance measured using multi-endmember spectral mixture analysis (MESMA) of a time series of Landsat TM/ETM+ images (2001, 2007, 2010) covering the 231 km stretch of the railway from south of Kaixinling Station to north of Chumaerhe Station. We found that the effect of QTR construction on vegetation abundance was limited to within 5.0 km of the tracks, the largest decrease, 2.9%, occurring within 0.125 km of the tracks from 2001 to 2007. There was only 0.4% further decrease in vegetation abundance from 2007 to 2010. We attributed the decrease in vegetation abundance within 0.125 km of the tracks mostly to the accumulation of drifting sand resulting from the barrier of the railway and the measures adopted to keep the sand away from the railway under the prevailing west or northwest winds. It appears that in this sensitive cold desert, vegetation damage was limited to the period of railway construction. [ABSTRACT FROM PUBLISHER]

Abstract: Temperature/emissivity estimation from remotely measured radiances generally assumes that scene elements represented by pixels in fact have a single emissivity spectrum and are isothermal. Thus, estimated temperatures and emissivities are the effective values that would be found if these simplified assumptions were met. In reality, the physical scene is neither homogeneous nor isothermal, and the effective values are not strictly representative of it. How much in error are they? In order to estimate this, a radiosity model used for predicting effective emissivity spectra and radiant temperatures for rough surfaces has been developed. Here we compare the computer model results to analytic model results in order to verify that the computer model is working properly. We validate the model against spectra measured in the field using a hyperspectral imaging spectrometer and a centimeter-scale DTM of the test scene acquired using a tripod-based LiDAR. The discrepancies between analytical and modeled values are less than 0.01%. Modeled emissivity spectra deviate from the measured by no more than 0.015 emissivity units. Modeled kinetic temperature on average deviates from measured by less than 1K over the course of a day. [Copyright &y& Elsevier]

Abstract: Land surface temperature and emissivity are independent variables, and the thermal-infrared spectral radiance measured in remote sensing is dependent on both. Therefore the inverse Planck equation is under-determined, with two unknowns and a single measurement. Practical inversion algorithms designed to calculate temperature and emissivity from the measurements cannot do a perfect job of separation, and recovered temperature and emissivity may co-vary. For ASTER images, validation studies of recovered temperature and emissivity, regarded individually, have shown that they are within the precision and accuracy limits predicted in designing the ASTER TES algorithm used to calculate the standard products AST05 and AST08. Nevertheless, a closer look at emissivity recovered for water targets shows that emissivity appears to vary, incorrectly, as a function of temperature. One cause of this is electronic striping; another is incomplete characterization of atmospheric temperature and humidity profiles used in compensation for atmospheric absorption and path radiance. The linkage varies from band to band, with the greatest emissivity effect of −0.0003K−1 for ASTER band 12 (9.1μm) relative to band 13 (10.6μm). Although this inaccuracy in emissivity is small, it can approach or exceed the inaccuracy prediction of ±0.015 for the standard product when the entire gamut of terrestrial water and land temperatures is examined. Therefore, spatial filtering and upgrading the atmosphere compensation algorithm to use water-vapor scaling should be considered in making AST05 and AST08. [Copyright &y& Elsevier]

Objectives: To review the published literature concerning robotic surgery and its applications in the management of cervical carcinoma. Methods: We electronically searched the MEDLINE from January 1990 until June 2010. We cross-examined article references to identify relevant articles not detected by the electronic search. Results: The majority of the reported literature consisted of case series, case reports or retrospective comparisons. Twenty-one articles were included in this review covering the different surgical applications: (5) radical trachelectomy, (12) radical hysterectomy, (3) pelvic exenteration and one parametrectomy. Conclusion: Robotic surgery enabled more gynaecological oncologists to perform more complex procedures safely while maintaining the minimal access approach. [ABSTRACT FROM AUTHOR]

Abstract: The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) has operated since 19 December 1999 from NASA''s Terra Earth-orbiting, sun-synchronous satellite. The Temperature–Emissivity Separation (TES) algorithm is used to calculate surface temperature and emissivity standard products, predicted to be within +1.5K and +0.015 of correct values, respectively. Analyses of time sequences of ASTER images showing validation sites at Lake Tahoe, California, the Salton Sea, California, Railroad Valley Nevada, and the island of Hawaiʻi demonstrate that TES generally performs within these limits. The validation experiments also demonstrate that, under unusual atmospheric conditions of anomalously high humidity or spatial variability, atmospheric compensation can be incomplete and errors in temperature and emissivity images can be larger than anticipated. [Copyright &y& Elsevier]

Abstract: Constructing a tectonic history of a planetary surface requires determining precise fault ages, a task not always possible with current analytical methods. Here we introduce a new method to constrain the ages of faults, improving upon earlier methods that used cross-cutting relationships with crater-dated host surfaces, and apply it to faulted terrains by counting all craters and categorizing them into “faulted,” “unfaulted” and “unclear” types to date deformation directly. Additionally, we construct a simple probabilistic model to account for regions of low fault density. This new technique is applied to the tectonically complex Thaumasia plateau, Mars, to assess the timing of regional faulting and demonstrate its usefulness and ease of application. [Copyright &y& Elsevier]

Abstract: The self-shadowing of conifer canopies results from the size and arrangement of trees within a stand and is a first-order term controlling radiance from forested terrain at common pixel scales of tens of meters. Although self-shadowing is a useful attribute for forest remote-sensing classification, compensation for the topographic effects of self-shadowing has proven problematic. This study used airborne canopy LiDAR measurements of 80 Pacific Northwest, USA conifer stands ranging in development stage from pre-canopy closure to old-growth in order to model canopy self-shadowing for four solar zenith angles (SZA). The shadow data were compared to physical measurements used to characterize forest stands, and were also used to test and improve terrain compensation models for remotely sensed images of forested terrain. Canopy self-shadowing on flat terrain strongly correlates with the canopy''s geometric complexity as measured by the rumple index (canopy surface area/ground surface area) (R 2 =0.94–0.87 depending on SZA), but is less correlated with other stand measurements: 95th percentile canopy height (R 2 =0.68), mean diameter at breast height (dbh) (R 2 =0.65), basal area ha−1 (R 2 =0.18), and canopy stem count ha−1 (R 2 =0.18). The results in this paper support interpretation of self-shadowing as a function of canopy complexity, which is an important ecological characteristic in its own right. Modeling of canopy self-shadowing was used to assess the accuracy of the Sun-Canopy-Sensor (SCS) topographic correction, and to develop a new empirical Adaptive Shade Compensation (ASC) topographic compensation model. ASC used measured shadow (as an estimate of canopy complexity) and the SCS term (to describe the illumination geometry) as independent variables in multiple regressions to determine the topographic correction. The ASC model provided more accurate radiance corrections with limited variation in results across the full range of canopy complexities and incidence angles. [Copyright &y& Elsevier]

Desert pavements can be detected through multi-spectral polarization measurements of reflected sunlight both in and out of the solar principle plane. The combination of polarization and color distinguishes desert pavements from other desert landforms and vegetation. Desert pavements linearly polarize and impart a blueness to sunlight reflected at visible wavelengths. The polarization and color of skylight reflected at high emission angles is also preserved. The polarization properties of desert pavements are dominated by Fresnel reflection at large phase angles and by multiple scattering at low phase angles, causing significant positive and small negative polarization, respectively. [Copyright &y& Elsevier]

Abstract: The Tien Shan of Kyrgyzstan contains multiple moraines and drift from late Quaternary glaciations. The spatial/temporal distribution of the glaciers inferred from the moraines suggests that the main factor controlling glacier advance here was the availability of moisture. The dominant modern climatic signatures in northern Central Asia include orographic thunderstorms in summer, cold and dry Siberian high-pressure cells in winter, and westerly cyclonic storms from the North Atlantic and eastern Mediterranean in spring and fall. Changes in any of these systems during the late Quaternary would have varied precipitation delivery to, and glacier growth in the Kyrgyz Tien Shan. Geomorphic mapping and reconnaissance-level 10Be cosmic-ray exposure dating of moraine sequences in six drainages indicate that there were multiple “maximum” advances of similar extents and equilibrium-line depressions across the range. Glaciers in the north and east of the Kyrgyz Tien Shan last advanced to their maximum positions during marine oxygen isotope stage (MIS) 5 and again during MIS 4, while in the south and west of the range advance occurred during MIS 3. In contrast to maritime Europe and North America, there is no evidence of a major glacial advance during MIS 2. Glacier advances during MIS 2 and since were restricted to the vicinity of modern glaciers, allowing the older glacial record to be preserved well. [Copyright &y& Elsevier]

Abstract: Late Pleistocene glaciers around Darhad Basin advanced to near their maximum positions at least three times, twice during the Zyrianka glaciation (at ∼17–19 ka and ∼35–53 ka), and at least once earlier. The Zyrianka glaciers were smaller than their predecessors, but the equilibrium-line altitude (ELA) difference was <75 m. End moraines of the Zyrianka glaciers were ∼1600 m asl; ELAs were 2100–2400 m asl. 14C and luminescence dating of lake sediments confirm the existence of paleolake highstands in Darhad Basin before ∼35 ka. Geologic evidence and 10Be cosmic-ray exposure dating of drift suggests that at ∼17–19 ka the basin was filled at least briefly by a glacier-dammed lake ∼140 m deep. However, lake sediments from that time have not yet been recognized in the region. A shallower paleolake briefly occupied the basin at ∼11 ka, but between ∼11 and 17 ka and after ∼10 ka the basin was probably largely dry. The timing of maximum glacier advances in Darhad appears to be approximately synchronous across northern Mongolia, but different from Siberia and western Central Asia, supporting the inference that paleoclimate in Central Asia differed among regions. [Copyright &y& Elsevier]

Abstract: Objective. : To describe the clinical features, treatment and outcome of all consecutive patients with placental site trophoblastic tumour (PSTT) treated at the Sheffield Trophoblast Centre and to compare these findings to other reports. Method. : All cases of PSTT on the Sheffield Trophoblastic Tumour Centre database from 1984 to 2004 were reviewed. Data obtained included age at diagnosis, antecedent pregnancy (AP), interval from antecedent pregnancy until diagnosis, presenting features, presenting serum human chorionic gonadotrophin hormone (hCG) level, number and sites of metastases, treatment received, outcome and follow-up. Results. : Seventeen patients with PSTT were identified from the database which incorporates a total of 7489 cases of trophoblastic disease. Fourteen (70.6%) were more than 30 years old at presentation; 5 were over 40. The median interval from pregnancy to diagnosis was 18 months (range 6 months to 22 years). The outcome of antecedent pregnancy was a female in 11 out of the 13 patients where the sex was known. Eleven (70.6%) of patients presented with irregular vaginal bleeding, with or without a preceding period of amenorrhoea. All 8 patients with non-metastatic (Stage I) disease were alive and well after hysterectomy (6), chemotherapy alone (1) or hysterectomy and chemotherapy (1) whereas only 4 of 9 patients with metastatic (Stage III/IV) disease were alive and well after treatment with chemotherapy and hysterectomy. Conclusion. : PSTT is rare and accounts for 0.23% cases of gestational trophoblastic disease referred to this centre. It has a variety of presenting features and its course is unpredictable. Metastatic involvement and antecedent pregnancy interval greater than 4 years are poor prognostic factors. Hysterectomy is the primary mode of treatment in the majority of cases. However, chemotherapy can still play a major role when curative surgery is not feasible. [Copyright &y& Elsevier]

Geological mapping based on topographic analysis of Mars Orbiter Laser Altimeter (MOLA) data, together with photointerpretation of Mars Orbiter Camera (MOC) images and thermodynamic and heat-flow considerations, frame a new hypothesis for the formation of Martian outflow channels through catastrophic dewatering of evaporite deposits. MOLA transects across Valles Marineris show that the valley is located at the crest of a 3-km-high topographic bulge on the flank of the much larger Tharsis Rise. Interpretation of MOC images showing layered deposits within Valles Marineris as unconformably underlying Hesperian-age lava flows means that these thick deposits, thought to contain hydrous sulfates, were heated by an increased geothermal gradient due to development of Tharis. Increased temperatures adequate to dehydrate hydrous evaporites would trigger significant volumetric expansion and catastrophically release tremendous amounts of overpressured water. [ABSTRACT FROM AUTHOR]

We use multispectral MODIS/ASTER Airborne Simulator (MASTER) data collected at Mt. Rainier, Washington (USA) to map spatial covariance between snowpack properties and to evaluate techniques for quantitative estimation of reflectance, grain size, and temperature. The late-August MASTER images reveal a distinct pattern of snow contaminant content, grain size, and temperature related to a recent snowfall and late-summer melting. Spatial correlation between grain size and temperature patterns suggests that rapid destructive metamorphism of the fresh snow occurred when temperatures were near 0 °C. We use 10 specific locations to evaluate hemispherical–directional reflectance factor (HDRF), grain size, and temperature retrievals. We map relative snow contaminant content using visible (0.4–0.8 μm) HDRF spectra. Atmospheric correction and topographic modeling limit the accuracy of HDRF estimates. We use MASTER-derived spectra near 1.8 and 2.2 μm to estimate optical grain size (by comparison to modeled layers of ice spheres) and physical grain size (by comparison to measured spectra with known physical grain size and by correlation to ground measurements). Estimated physical grain sizes were less than estimated optical grain sizes. Differing definitions of optical and physical grain sizes could contribute to this discrepancy. Limitations at 1.8 and 2.2 μm, including reduced discrimination between larger grain radii (>∼500 μm physical, >∼200 μm optical) and low signal-to-noise ration with atmospheric effects and decreasing solar irradiance, suggest that grain size retrieval may be improved at other wavelengths (e.g., 1.1 μm). Accounting for uncertainty in emissivity, atmospheric correction, and detector noise, we estimate systematic errors in our radiant temperatures at <1.8 °C. This study shows both strengths and limitations for coregistered visible, short-wave infrared, and thermal infrared images to estimate snowpack properties and reveal their spatial coherence. [Copyright &y& Elsevier]

We identified stages of regrowth in replanted clearcuts in Douglas-fir/western hemlock forests in the Gifford Pinchot National Forest, southern Washington, USA, using a simple four-endmember constrained linear spectral mixing model applied to a multispectral Landsat Thematic Mapper image in order to separate and quantify spectral contributions from significant scene components. Spectral unmixing produces images of the fractional amount of the spectral endmembers, which were green vegetation, nonphotosynthetic vegetation, soil and "shade," which includes topographic shading and shadows. Changes in endmember fractions correspond to changes in surface composition (as viewed from above). Unresolved shadows comprise the primary indicator of canopy structure and hence, regrowth stage. To isolate shadows, shading predicted from a digital elevation model was removed from the image before mixture analysis. As stands regrow, the surface cover shifts from initial high proportion of slash and exposed soil, and low proportions of green vegetation and shadows, to low fractions of stems and soil with high fractions of green vegetation and shadows. This shift in surface composition defines a regrowth trend in an endmember fraction data space. Projection of data onto this line allows estimation of structural stage and stand age, and provides a framework for remote mapping and monitoring of forest regrowth. Field analysis of 495 forest stands, representing stand structural stages ranging from newly replanted cuts to stands greater than 250 years in age, was used to assess the accuracy and precision of predicted structural stages and stand ages. The spectral unmixing approach can be used to evaluate and monitor forest regrowth quickly over large areas of the Pacific Northwest forests, and is extendible to mapping basic vegetation community type as well as structural stage. [ABSTRACT FROM AUTHOR]

Presents information on a study that developed an autonomous atmospheric compensation (AAC) algorithm to estimate and compensate for the atmospheric effect. Difference in the spatial and spectral variability between land surface and atmosphere parameters; Details on the derivation of AAC; Assessment of the uncertainties of ACC implementation; Results of the ACC application to a hyperspectral thermal infrared image.

Salter-Harris II fractures of the distal radius can result in serious complications. The aim of this study was to measure the fracture-physis distance using point-of-care ultrasound (POCUS) to determine whether a certain distance is associated with Salter-Harris II fractures, compared with other fracture types, in a cohort of children with X-ray-identified distal radius fractures. Participants were from a parent diagnostic study conducted in an Australian tertiary pediatric emergency department, which prospectively evaluated the diagnosis of pediatric distal forearm fractures using POCUS compared against X-ray. Nurse practitioners, who underwent 2 h of training, administered a six-view POCUS protocol in clinically non-angulated pediatric forearm injuries prior to X-ray. This was a secondary analysis of data from the parent study. The 122 participants with X-ray-identified distal radius fractures from the parent study had their POCUS images interpreted by two emergency physician sonologists, who measured the fracture-physis distance. The median and maximum fracture-physis distances for Salter-Harris II fractures (n = 19) were 8.00 and 9.85 mm, whereas minimum and median distances for incomplete fractures (n = 22) were 10.20 and 15.98 mm, and those for complete fractures (n = 9) were 10.85 and 12.85 mm. Buckle fracture (n = 72) distances ranged from 4.35 to 26.55 mm, with a median of 13.65 mm. In children diagnosed with a distal radius fracture on X-ray, a fracture-physis distance cutoff of 1 cm differentiated Salter-Harris II fractures from other cortical breach fracture types, but not buckle fractures. Although this exploratory study suggests the "POCUS 1-cm rule" could be used as a secondary sign to augment the diagnosis of Salter-Harris II distal radius fractures using POCUS, further research is required to validate this measurement prospectively. [ABSTRACT FROM AUTHOR]

Presents information on a study that proposed a contextual approach for minimizing the geometric and systematic errors associated with the acquisition and coregistration of satellite image and digital terrain model (DTM). Errors related to topographic correction; Contextual topographic correction approach; Algorithm; Data analysis.

Focuses on the collection of five bands of thermal infrared (TIR) data by the advanced spaceborne thermal emission and reflection radiometer (ASTER) scanner on the United States National Aeronautics and Space Administration's (NASAs) earth observing system (EOS)-AM1 satellite. Difficulty of temperature/emissivity separation (TES); Prediction of minimum emissivity from the spectral contrast of ratioed values; Importance of land surface temperatures.

Presents cosmogenic age estimates for earthquake recurrence intervals and debris flow fan deposition in Owens Valley, California. Geomorphic surfaces; Isotopic data; Calculations; Model exposures; Uncertainties.

Objective: To identify lessons learned locally from the invasive cervical cancer audit. To estimate the impact that the application of 'Duty of Candour' may have upon our future service provision. Methods: Retrospective cohort study with interval analysis of all women diagnosed with cervical cancer at Sheffield Teaching Hospitals NHS Foundation Trust between 1 April 2007 to 31 December 2019. Data were collected prospectively with retrospective categorisation by screening history and invasive cervical cancer audit outcomes as satisfactory, satisfactory with learning points, and unsatisfactory. Statistical analysis was performed using the chi‐squared test and paired t‐test. Results: Cervical cancer was diagnosed in 344 women. Seventy‐eight (23%) had no record of prior cervical cytology, 108 (31%) had delayed attendance to the screening programme, 102 (30%) were detected by routine screening, and 56 (16%) were screening programme compliant. Satisfactory management was undertaken in 301 (87.5%) cases, 26 cases (7.5%) were satisfactory with learning points, and 17 cases (5%) were considered as unsatisfactory. Conclusions: Seventeen cases were applicable to the Duty of Candour process equating to 1.3 cases per year, incurring minimal impact upon future service provision. Invasive audit categorisation is subject to bias, however, with the potential for considerable intra‐ and inter‐observer variation; the authors accordingly recommend that a further study be conducted to investigate both the consistency and reproducibility of the invasive cervical cancer audit categorisation. The majority of invasive cervical cancer audit cytology reviews considered as satisfactory with learning points were upgraded from negative to glandular dyskaryosis; however, audit outcome categorisation is subject to bias with potential for considerable intra‐ and inter‐observer variation. [ABSTRACT FROM AUTHOR]

Validation of emissivity (ε) retrievals from spaceborne thermal infrared (TIR) sensors typically requires spatial extrapolations over several orders of magnitude for a comparison between centimeter-scale laboratory ε measurements and the common decameter and lower resolution of spaceborne TIR data. In the case of NASA's Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) temperature and ε separation algorithm (TES), this extrapolation becomes especially challenging because TES was originally designed for the geologic surface of Earth, which is typically heterogeneous even at centimeter and decameter scales. Here, we used the airborne TIR hyperspectral Mako sensor with its 2.2 m/pixel resolution, to bridge this scaling issue and robustly link between ASTER TES 90 m/pixel emissivity retrievals and laboratory ε measurements from the Algodones dune field in southern California, USA. The experimental setup included: (i) Laboratory XRD, grain size, and TIR spectral measurements; (ii) radiosonde launches at the time of the two Mako overpasses for atmospheric corrections; (iii) ground-based thermal measurements for calibration, and (iv) analyses of ASTER day and night ε retrievals from 21 different acquisitions. We show that while cavity radiation leads to a 2% to 4% decrease in the effective emissivity contrast of fully resolved scene elements (e.g., slipface slopes and interdune flats), spectral variability of the site when imaged at 90 m/pixel is below 1%, because at this scale the dune field becomes an effectively homogeneous mixture of the different dune elements. We also found that adsorption of atmospheric moisture to grain surfaces during the predawn hours increased the effective ε of the dune surface by up to 0.04. The accuracy of ASTER's daytime emissivity retrievals using each of the three available atmospheric correction protocols was better than 0.01 and within the target performance of ASTER's standard emissivity product. Nighttime emissivity retrievals had lower precision (<0.03) likely due to residual atmospheric effects. The water vapor scaling (WVS) atmospheric correction protocol was required to obtain accurate (<0.01) nighttime ASTER emissivity retrievals. [ABSTRACT FROM AUTHOR]

Permafrost is degrading under current warming conditions, disrupting infrastructure, releasing carbon from soils, and altering seasonal water availability. Therefore, it is important to quantitatively map the change in the extent and depth of permafrost. We used satellite images of land-surface temperature to recognize and map the zero curtain, i.e., the isothermal period of ground temperature during seasonal freeze and thaw, as a precursor for delineating permafrost boundaries from remotely sensed thermal-infrared data. The phase transition of moisture in the ground allows the zero curtain to occur when near-surface soil moisture thaws or freezes, and also when ice-rich permafrost thaws or freezes. We propose that mapping the zero curtain is a precursor to mapping permafrost at shallow depths. We used ASTER and a MODIS-Aqua daily afternoon land-surface temperature (LST) timeseries to recognize the zero curtain at the 1-km scale as a "proof of concept." Our regional mapping of the zero curtain over an area around the 7000 m high volcano Ojos del Salado in Chile suggests that the zero curtain can be mapped over arid regions of the world. It also indicates that surface heterogeneity, snow cover, and cloud cover can hinder the effectiveness of our approach. To be of practical use in many areas, it may be helpful to reduce the topographic and compositional heterogeneity in order to increase the LST accuracy. The necessary finer spatial resolution to reduce these problems is provided by ASTER (90 m). [ABSTRACT FROM AUTHOR]

To evaluate the diagnostic accuracy of ultrasound secondary signs of fractures in pediatric patients aged 5–15 y presenting to the emergency department with a clinically non-deformed distal forearm injury. This diagnostic study was conducted in South East Queensland, Australia. Emergency clinicians performed point-of-care ultrasound on eligible patients and recorded secondary signs of fractures (pronator quadratus hematoma [PQH] sign, periosteal hematoma, visible angulation) or physeal fractures (fracture-to-physis distance [FPD], physis alteration). The reference standard was the final fracture diagnosis determined by expert panel. The primary outcome was the diagnostic accuracy of secondary signs for cortical breach and physeal fractures. Diagnostic statistics were reported for each relevant secondary sign. A total of 135 participants were enrolled. The expert panel diagnosed 48 "no" fracture, 52 "buckle" fracture and 35 "other" fracture. All "other" fractures were cortical breach fractures and included 15 Salter–Harris II fractures. The PQH sign demonstrated high sensitivity and moderate specificity to diagnose cortical breach fractures (91%, 95% Confidence Interval [CI] 78%–97% and 82%, 73%–88%). Poor sensitivity but high specificity was observed for the visible angulation and periosteal hematoma secondary signs. FPD <1cm showed perfect sensitivity and moderate specificity (100%, 80%–100% and 85%, 78%–90%) for diagnosis of Salter–Harris II fracture. Conversely, physis alteration showed poor sensitivity but excellent specificity (40%, 20%–64% and 99%, 95%–100%) for the diagnosis of Salter–Harris II fractures. Ultrasound secondary signs showed good diagnostic accuracy for both cortical breach fractures and Salter–Harris II fractures. Future research should consider optimal use of secondary signs to improve diagnostic accuracy. [ABSTRACT FROM AUTHOR]

Arising from: J. W. Head et al. 434, 346–351 (2005); Head et al. reply.Head et al. interpret spectacular images from the Mars Express high-resolution stereo camera as evidence of geologically recent rock glaciers in Tharsis and of a piedmont (‘hourglass’) glacier at the base of a 3-km-high massif east of Hellas. They attribute growth of the low-latitude glaciers to snowfall during periods of increased spin-axis obliquity. The age of the hourglass glacier, considered to be inactive and slowly shrinking beneath a debris cover in the absence of modern snowfall, is estimated to be more than 40 Myr. Although we agree that the maximum glacier extent was climatically controlled, we find evidence in the images to support local augmentation of accumulation from snowfall through a mechanism that does not require climate change on Mars. [ABSTRACT FROM AUTHOR]

Wetlands are valuable ecosystems for maintaining biodiversity, but are vulnerable to climate change and land conversion. Despite their importance, wetland hydrology is poorly understood as few tools exist to monitor their hydrologic regime at a landscape scale. This is especially true when monitoring hydrologic change at scales below 30 m, the resolution of one Landsat pixel. To address this, we used spectral mixture analysis (SMA) of a time series of Landsat satellite imagery to reconstruct surface-water hydrographs for 750 wetlands in Douglas County, Washington State, USA, from 1984 to 2011. SMA estimates the fractional abundance of spectra representing physically meaningful materials, known as spectral endmembers, which comprise a mixed pixel, thus providing sub-pixel estimates of surface water extent. Endmembers for water and sage steppe were selected directly from each image scene in the Landsat time series, whereas endmembers for salt and wetland vegetation were derived from a mean spectral signature of selected dates spanning the 1984–2011 timeframe. This method worked well (R 2 = 0.99) for even small wetlands (< 1800 m 2 ) providing a wall-to-wall dataset of reconstructed surface-water hydrographs for wetlands across our study area. We have validated this method only in semi-arid regions. Further research is necessary to extend its validity to other environments. This method can be used to better understand the role of hydrology in wetland ecosystems and as a monitoring tool to identify wetlands undergoing abnormal change. [ABSTRACT FROM AUTHOR]

Post-coital bleeding (PCB) is a poor predictive factor for cancer and should not be managed as urgent referral. Urgent referral to colposcopy is justified however, in the presence of a visible suspicion of cervical cancer. This retrospective cohort study of women attending a clinical indications referral service aims to identify the risk of pre-malignant and malignant disease in women with clinical indication referrals to colposcopy. Thirty-seven of 3521 women (1%) were diagnosed with pre-malignant cervical or endometrial disease; 14 women (0.4%) were diagnosed with cancer (11 cervix, three endometrial). To detect one cancer in women referred with an abnormal cervix, one would need to see 70 women; to detect one cancer in women referred with PCB one would need to see 790 women. Improved education in primary care and obstetrics and gynaecology training is key to improving clinical indications referral services, which is otherwise an effective and efficient service. What is already known on this subject? Post-coital bleeding is a poor predictive factor for cancer and should not be considered an urgent referral. What do the results of this study add? The presence of a visible suspicion of cervical cancer however does warrant urgent referral as approximately one in 70 women will have a malignancy detected. What are the implications of these findings for clinical practice and/or further research? Improved education in primary care and obstetrics and gynaecology training is the key to improving clinical indications referral services [ABSTRACT FROM AUTHOR]

The need to monitor the Earth's surface over a range of spatial and temporal scales is fundamental in ecosystems planning and management. Change-Vector Analysis (CVA) is a bi-temporal method of change detection that considers the magnitude and direction of change vector. However, many multispectral applications do not make use of the direction component. The procedure most used to calculate the direction component using multiband data is the direction cosine, but the number of output direction cosine images is equal to the number of original bands and has a complex interpretation. This paper proposes a new approach to calculate the spectral direction of change, using the Spectral Angle Mapper and Spectral Correlation Mapper spectral-similarity measures. The chief advantage of this approach is that it generates a single image of change information insensitive to illumination variation. In this paper the magnitude component of the spectral similarity was calculated in two ways: as the standard Euclidean distance and as the Mahalanobis distance. In this test the best magnitude measure was the Euclidean distance and the best similarity measure was Spectral Angle Mapper. The results show that the distance and similarity measures are complementary and need to be applied together. [ABSTRACT FROM AUTHOR]

Abstract: Geomorphic, stratigraphic, geotechnical, and biogeographic evidence indicate that failure of a Pleistocene ice dam between 15.5 and 26ka generated a megaflood from Glacial Lake Atna down the Matanuska Valley. While it has long been recognized that Lake Atna occupied ≥9000km2 of south-central Alaska''s Copper River Basin, little attention has focused on the lake''s discharge locations and behaviors. Digital elevation model and geomorphic analyses suggest that progressive lowering of the lake level by decanting over spillways exposed during glacial retreat led to sequential discharges down the Matanuska, Susitna, Tok, and Copper river valleys. Lake Atna''s size, ∼50ka duration, and sequential connection to four major drainages likely made it a regionally important late Pleistocene freshwater refugium. We estimate a catastrophic Matanuska megaflood would have released 500–1400km3 at a maximum rate of ≥3×106 m3 s−1. Volumes for the other outlets ranged from 200 to 2600km3 and estimated maximum discharges ranged from 0.8 to 11.3×106 m3 s−1, making Lake Atna a serial generator of some of the largest known freshwater megafloods. [Copyright &y& Elsevier]

Abstract: Glaciers in the southern Himalayas advanced in the early Holocene despite an increase in incoming summer solar insolation at the top of the atmosphere. These glacier advances are in contrast to the smaller alpine glaciers in the western and northern regions of Central Asia. Two different glacier mass-balance models are used to reconcile this Holocene glacier history with climate by quantifying the change in equilibrium-line altitudes (ELA) for simulated changes in Holocene climate. Both ELA models clearly show that the lowering of ELAs in the southern Himalayas is largely due to a decrease in summer temperatures, and that an increase in monsoonal precipitation accounts for less than 30% of the total ELA changes. The decrease in summer temperatures is a dynamic response to the changes in solar insolation, resulting in both a decrease in incoming shortwave radiation at the surface due to an increase in cloudiness and an increase in evaporative cooling. In the western and northern zones of Central Asia, both ELA models show a rise in ELAs in response to a general increase in summer temperatures. This increase in temperatures in the more northern regions is a direct radiative response to the increase in summer solar insolation. [Copyright &y& Elsevier]

Abstract: A suite of geomorphological and sedimentological features in the catchment of the upper Yenisei River in the Sayan mountains of southern Siberia testifies to the occurrence of cataclysmic floods that flowed down the river. Evidence of large-scale high-energy flood events includes: 1) gravel dunes, up to a few meters high and spaced 50 to 80 m apart, in the Kyzyl Basin 2) landforms such as hanging valleys and paleochannels and 3) flood sediments in a tributary valley. The origins of the Yenisei floods were likely diverse due to complex hydrological processes operating in the Sayan mountains. The possibilities include failures of multiple, variably impounded (ice, sedimentary, tectonic scarp, and lava flow dams) paleolakes in the two large intermontane basins of Darkhadyn Khotgor and Todza, and other minor basins, in the upper Yenisei River catchment. Dating techniques applied to the paleolakes in the Darkhadyn Khotgor and Todza basins revealed their formation during various periods in the middle–late Pleistocene and Holocene. Flooding from the Darkhadyn Khotgor appears to explain many of the inferred flood features, although contributions by flooding from other paleolake basins cannot be ruled out. Computer simulation of the flooding caused by a Darkhadyn Khotgor paleolake ice-dam failure indicates a probable peak discharge of ∼3.5×106 m3 s−1, approximately one-fifth that of the floods that formed the Channeled Scabland in the U.S.A. Many of the outburst events probably occurred in the late Quaternary, but earlier floods could also have occurred. [Copyright &y& Elsevier]

Abstract: Land surface emissivity retrieval over agricultural regions is important for energy balance estimations, land cover assessment and other related environmental studies. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) produces images of sufficient spatial resolution (from 15 m to 90 m) to be of use in agricultural studies, in which fields of crops are too small to be well-resolved by low resolution sensors. The ASTER project generates land surface emissivity images as a Standard Product (AST05) using the Temperature/Emissivity Separation (TES) algorithm. However, the TES algorithm is prone to scaling errors in estimating emissivities for surfaces with low spectral contrast if the atmospheric correction is inaccurate. This paper shows a comparison between the land surface emissivity estimated with the TES algorithm and from a simple approach using the Normalized Difference Vegetation Index (NDVI) for five ASTER images (28 June 2000, 15 August 2000, 31 August 2000, 28 April 2001 and 02 August 2001) of the agricultural area of Barrax (Albacete, Spain). The results indicate that differences are <1% for ASTER band 13 (10.7 μm) and <1.5% for band 14 (11.3 μm), but >2% for bands 10 (8.3 μm), 11 (8.6 μm) and 12 (9.1 μm). The emissivities for the five ASTER bands were tested against in situ measurements carried out with the CIMEL CE 312-2 field radiometer, the NDVI method giving root mean square errors (RMSE) <0.005 over vegetated areas and RMSE <0.015 over bare soil, and the TES algorithm giving RMSE ∼0.01 for vegetated areas but RMSE >0.03 over bare soil. The errors and inconsistencies for ASTER bands 13 and 14 are within those anticipated for TES, but the greater errors for bands 10–12 suggest the presence of problems related to atmospheric compensation and model assumptions about soil spectra. The NDVI method uses visible/near-infrared data co-acquired with the thermal images to estimate vegetation cover and, hence, provides an independent constraint on emissivity. The success of this approach suggests that it may be useful for daytime images of agricultural or other heavily vegetated areas, in which the TES algorithm has occasional failures. [Copyright &y& Elsevier]

Abstract: Surface-temperature (T) and emissivity (ε) estimation from remotely sensed mid-infrared (MIR: 3–5 μm) data requires modifications to existing long-wave infrared (LWIR: 8–12 μm) T/ε separation algorithms because of the significantly different characteristics of Planck''s function between the MIR and LWIR wavelength regions and the strong effects of reflected solar irradiance in the MIR. A modified version of the normalized emissivity method (NEM), utilizing independently scaled maximum emissivities in each channel, was applied to thermal data acquired by the Multispectral Thermal Imager (MTI) with two MIR channels, J (3.81 μm) and K (4.97 μm), and three LWIR channels, L (8.26 μm), M (8.65 μm), and N (10.51 μm). Atmosphere-free simulations of T and ε retrieval over a wide variety of terrestrial surfaces yielded T values within ± 0.75 K of ‘true T’ in the range of 270–330 K and ε values within ±0.011 of true ε in channels L, M and N, and ±0.019 and ±0.023 in channels K and J, respectively. The algorithm was tested successfully using MTI data over the Mauna Loa caldera in Hawaii. Unconstrained effects of shading and unresolved shadows in channel J day time data, and the strong atmospheric effects in channel K limit the application of the algorithm, in its present form, to night-time data. [Copyright &y& Elsevier]

The sub-pixel spectral detectability of obsidian and ceramic artifacts against typical soil backgrounds from two study areas in the western USA was analytically evaluated to determine the usefulness of remote sensing as a tool for artifact detection [in the visible (VIS), near-infrared (NIR), and/or thermal-infrared (TIR) portion of the spectrum]. In the VIS/NIR, surface concentrations of pottery needed to be 85% or greater to be detected against backgrounds of soil, rock, and vegetation. At the same wavelengths, obsidian is spectrally similar to shade and cannot be uniquely detected unless the effects of shade are independently removed. In cases where shade is not a major factor, obsidian at concentrations of 2–3% can be detected. In the TIR, pottery thresholds ranged from 12 to 48%, depending on the composition of the background. Obsidian detection thresholds ranged from 4 to 25% cover. These results indicate that surface mapping using remote sensing in the TIR has the potential to be an effective tool for prioritizing large areas for future ground surveys. [Copyright &y& Elsevier]