11 research outputs found

    Performance of GEDI space-borne LiDAR for quantifying structural variation in the temperate forests of South-Eastern Australia

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    Monitoring forest structural properties is critical for a range of applications because structure is key to understanding and quantifying forest biophysical functioning, including stand dynamics, evapotranspiration, habitat, and recovery from disturbances. Monitoring of forest structural properties at desirable frequencies and cost globally is enabled by space-borne LiDAR missions such as the global ecosystem dynamics investigation (GEDI) mission. This study assessed the accuracy of GEDI estimates for canopy height, total plant area index (PAI), and vertical profile of plant area volume density (PAVD) and elevation over a gradient of canopy height and terrain slope, compared to estimates derived from airborne laser scanning (ALS) across two forest age-classes in the Central Highlands region of south-eastern Australia. ALS was used as a reference dataset for validation of GEDI (Version 2) dataset. Canopy height and total PAI analyses were carried out at the landscape level to understand the influence of beam-type, height of the canopy, and terrain slope. An assessment of GEDI’s terrain elevation accuracy was also carried out at the landscape level. The PAVD profile evaluation was carried out using footprints grouped into two forest age-classes, based on the areas of mountain ash (Eucalyptus regnans) forest burnt in the Central Highlands during the 1939 and 2009 wildfires. The results indicate that although GEDI is found to significantly under-estimate the total PAI and slightly over-estimate the canopy height, the GEDI estimates of canopy height and the vertical PAVD profile (above 25 m) show a good level of accuracy. Both beam-types had comparable accuracies, with increasing slope having a slightly detrimental effect on accuracy. The elevation accuracy of GEDI found the RMSE to be 10.58 m and bias to be 1.28 m, with an R2 of 1.00. The results showed GEDI is suitable for canopy densities and height in complex forests of south-eastern Australia

    High-efficiency, high-speed, and low-noise photonic quantum memory

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    We present a demonstration of simultaneous high-efficiency, high-speed, and low-noise operation of a photonic quantum memory. By leveraging controllable collisional dephasing in a neutral barium atomic vapor, we demonstrate a significant improvement in memory efficiency and bandwidth over existing techniques. We achieve greater than 95% storage efficiency and 26% total efficiency of 880 GHz bandwidth photons, with O(105)\mathcal{O}(10^{-5}) noise photons per retrieved pulse. These ultrabroad bandwidths enable rapid quantum information processing and contribute to the development of practical quantum memories with potential applications in quantum communication, computation, and networking

    Comparing different pneumoperitoneum (12 vs. 15 mmHg) pressures with cytokine analysis to evaluate clinical outcomes in patients undergoing robotic‐assisted laparoscopic radical cystectomy and intracorporeal robotic urinary diversion

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    © 2023 The Authors. BJUI Compass published by John Wiley & Sons Ltd on behalf of BJU International Company. This is an open access article under the terms of the Creative Commons Attribution License. https://creativecommons.org/licenses/by/4.0/Background: Robotic cystectomy is the mainstay surgical intervention for treatment‐refractory non muscle‐invasive and muscle‐invasive bladder cancer. However, paralytic ileus may complicate the postoperative recovery and may be a consequence of an inflammatory response associated with transient gut ischaemia. We have therefore investigated clinical, operative and inflammatory biomarker associations between paralytic ileus in the context of robotic cystectomy and intracorporeal ileal conduit urinary diversion. Methods: Prospective consecutive patients referred for robotic cystectomy were consented and included in the study, while patients >75 years old and converted to open procedure were excluded. The pneumoperitoneum pressure (PP) for carbon dioxide insufflation required to perform the procedure efficiently and safely was recorded (12 or 15 mmHg). We also recorded the postoperative days patients passed flatus and stools, whether they developed ileus, as well as other standard clinical and demographic data. The expression of select proinflammatory and anti‐inflammatory cytokines was determined by multiplex analysis using a cytometric bead array with changes in profiles correlated with the pressures applied and with the existence of an ileus. Results: Twenty‐seven patients were recruited, but only 20 were used in the study with 10 patients in each PP group. Seven patients were excluded all of whom had an extracorporeal ileal conduit formation. There were differences in the 40‐min shorter operative time and 1 day shorter length of stay, as well as passing flatus 1 day and stools 1.5 days earlier in the 12 mmHg compared with the 15 mmHg group. More patients had ileus in the 15 mmHg group vs 12 mmHg group (30% vs. 10.0%). These were not statistically significant. Similarly, there were no statistical differences in the expression of proinflammatory cytokines at the two different pressures or between patient groups, but there were outliers, with the median indicating nonsymmetrical distribution. By comparison, anti‐inflammatory cytokines showed some significant differences between groups, with IL‐6 and IL‐10 showing elevated levels post surgery. No statistical difference was observed between pressures or the existence of an ileus, but the maximum levels of IL‐6 and IL‐10 detected in some patients reflect a pressure difference. Conclusions: The initial findings of this novel scientific study indicated a higher risk of paralytic ileus postrobotic cystectomy and robotic intracorporeal urinary diversion when a higher pressure of 15 mmHg is used compared with 12 mmHg. Although further studies are required to establish the linkage between cytokine profile expression, pressure and ileus, our initial data reinforces the advantages of lower pressure robotic cystectomy and intracorporeal urinary diversion in patient outcomes.Peer reviewe

    Distribution of Surgical Smoke Particles within a Simulated Laparoscopic Cavity Utilizing an AirSeal® System

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    © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. (http://creativecommons.org/licenses/bync-nd/4.0/)An exploratory study was performed to determine the distribution of surgical smoke particulate matter (SSPM) and evacuation times within an AirSeal® System and a traditional insufflation access system in various simulated surgical scenarios. Identified trends showed statistical significance when setting the AirSeal® System to Low smoke evacuation that it reduces the percentage of particulate matter at the Access Port opening. Additionally, it was observed that when utilizing a laparoscopic tool a similar trend in particle distributions were seen between either insufflation and access system at the opening of the Access Port and trocar. Evacuation times for SSPM removal within the AirSeal® System showed an overall average to ≥ 95% reduction of 5.64 min within the surgical cavity, 3.69 min at the Access Port opening, and 3.61 min within the smoke evacuation line. The overall average for the traditional insufflation and access system was 9.38 min within the surgical cavity and 6.06 min at the trocar opening. Results showed that when using the traditional system compared to the AirSeal® System, it resulted in a percent change increase in evacuation times of 66.31% within the surgical cavity and 64.23% at the trocar opening.Peer reviewe

    Métis Peoples and Cancer: A Scoping Review of Literature, Programs, Policies and Educational Material in Canada

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    Much of the existing Indigenous cancer research focuses on First Nation populations or reports on pan-Indigenous data that include First Nations, Métis, and Inuit metrics together, which fails to capture the distinct lived realities, experiences of colonialism, and culture of each Indigenous group. The purpose of this scoping review was to summarize existing knowledge on cancer among Métis peoples in Canada, offering direction to researchers, institutions, and policymakers for future actions that enhance Métis-specific cancer surveillance and cancer care. We searched Embase, Medline, iPortal, and Proquest Theses and Dissertations databases, Google Scholar and Google, alongside ten websites relevant to cancer and Métis peoples. Two reviewers gathered 571 records. After screening, 77 records were included. Data show that Métis peoples experience higher behavioral risk factors, lower screening participation, higher cancer incidence for some cancers, and higher mortality rates compared to the non-Indigenous population. Existing research is piece-meal and researchers emphasize that there is inadequate Métis-specific cancer data. There is a need for targeted, Peoples-specific cancer control interventions to reduce these health inequities and a coordinated, Peoples-specific approach to cancer research. These efforts must involve collaboration among Métis Nations and organizations, provincial governments and agencies, researchers, and policymakers

    The health and cost implications of high body mass index in Australian Defence Force personnel

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    BACKGROUND: Frequent illness and injury among workers with high body mass index (BMI) can raise the costs of employee healthcare and reduce workforce maintenance and productivity. These issues are particularly important in vocational settings such as the military, which require good physical health, regular attendance and teamwork to operate efficiently. The purpose of this study was to compare the incidence of injury and illness, absenteeism, productivity, healthcare usage and administrative outcomes among Australian Defence Force personnel with varying BMI. METHODS: Personnel were grouped into cohorts according to the following ranges for (BMI): normal (18.5-24.9 kg/m²; n = 197), overweight (25-29.9 kg/m²; n = 154) and obese (≥30 kg/m²) with restricted body fat (≤28 % for females, ≤24 % for males) (n = 148) and with no restriction on body fat (n = 180). Medical records for each individual were audited retrospectively to record the incidence of injury and illness, absenteeism, productivity, healthcare usage (i.e., consultation with medical specialists, hospital stays, medical investigations, prescriptions) and administrative outcomes (e.g., discharge from service) over one year. These data were then grouped and compared between the cohorts. RESULTS: The prevalence of injury and illness, cost of medical specialist consultations and cost of medical scans were all higher (p <0.05) in both obese cohorts compared with the normal cohort. The estimated productivity losses from restricted work days were also higher (p <0.05) in the obese cohort with no restriction on body fat compared with the normal cohort. Within the obese cohort, the prevalence of injury and illness, healthcare usage and productivity were not significantly greater in the obese cohort with no restriction on body fat compared with the cohort with restricted body fat. The number of restricted work days, the rate of re-classification of Medical Employment Classification and the rate of discharge from service were similar between all four cohorts. CONCLUSIONS: High BMI in the military increases healthcare usage, but does not disrupt workforce maintenance. The greater prevalence of injury and illness, greater healthcare usage and lower productivity in obese Australian Defence Force personnel is not related to higher levels of body fat

    Performance of GEDI Space-Borne LiDAR for Quantifying Structural Variation in the Temperate Forests of South-Eastern Australia

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    Monitoring forest structural properties is critical for a range of applications because structure is key to understanding and quantifying forest biophysical functioning, including stand dynamics, evapotranspiration, habitat, and recovery from disturbances. Monitoring of forest structural properties at desirable frequencies and cost globally is enabled by space-borne LiDAR missions such as the global ecosystem dynamics investigation (GEDI) mission. This study assessed the accuracy of GEDI estimates for canopy height, total plant area index (PAI), and vertical profile of plant area volume density (PAVD) and elevation over a gradient of canopy height and terrain slope, compared to estimates derived from airborne laser scanning (ALS) across two forest age-classes in the Central Highlands region of south-eastern Australia. ALS was used as a reference dataset for validation of GEDI (Version 2) dataset. Canopy height and total PAI analyses were carried out at the landscape level to understand the influence of beam-type, height of the canopy, and terrain slope. An assessment of GEDI&rsquo;s terrain elevation accuracy was also carried out at the landscape level. The PAVD profile evaluation was carried out using footprints grouped into two forest age-classes, based on the areas of mountain ash (Eucalyptus regnans) forest burnt in the Central Highlands during the 1939 and 2009 wildfires. The results indicate that although GEDI is found to significantly under-estimate the total PAI and slightly over-estimate the canopy height, the GEDI estimates of canopy height and the vertical PAVD profile (above 25 m) show a good level of accuracy. Both beam-types had comparable accuracies, with increasing slope having a slightly detrimental effect on accuracy. The elevation accuracy of GEDI found the RMSE to be 10.58 m and bias to be 1.28 m, with an R2 of 1.00. The results showed GEDI is suitable for canopy densities and height in complex forests of south-eastern Australia

    Forest Structure Drives Fuel Moisture Response across Alternative Forest States

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    Climate warming is expected to increase fire frequency in many productive obligate seeder forests, where repeated high-intensity fire can initiate stand conversion to alternative states with contrasting structure. These vegetation–fire interactions may modify the direct effects of climate warming on the microclimatic conditions that control dead fuel moisture content (FMC), which regulates fire activity in these high-productivity systems. However, despite the well-established role of forest canopies in buffering microclimate, the interaction of FMC, alternative forest states and their role in vegetation–fire feedbacks remain poorly understood. We tested the hypothesis that FMC dynamics across alternative states would vary to an extent meaningful for fire and that FMC differences would be attributable to forest structural variability, with important implications for fire-vegetation feedbacks. FMC was monitored at seven alternative state forested sites that were similar in all aspects except forest type and structure, and two proximate open-weather stations across the Central Highlands in Victoria, Australia. We developed two generalised additive mixed models (GAMMs) using daily independent and autoregressive (i.e., lagged) input data to test the importance of site properties, including lidar-derived forest structure, in predicting FMC from open weather. There were distinct differences in fuel availability (days when FMC &lt; 16%, dry enough to sustain fire) leading to positive and negative fire–vegetation feedbacks across alternative forest states. Both the independent (r2 = 0.551) and autoregressive (r2 = 0.936) models ably predicted FMC from open weather. However, substantial improvement between models when lagged inputs were included demonstrates nonindependence of the automated fuel sticks at the daily level and that understanding the effects of temporal buffering in wet forests is critical to estimating FMC. We observed significant random effects (an analogue for forest structure effects) in both models (p &lt; 0.001), which correlated with forest density metrics such as light penetration index (LPI). This study demonstrates the importance of forest structure in estimating FMC and that across alternative forest states, differences in fuel availability drive vegetation–fire feedbacks with important implications for forest flammability

    Clinical outcomes of low‑pressure pneumoperitoneum in minimally invasive urological surgery

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    © The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature 2021. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1007/s11701-021-01349-7The adoption of minimally invasive laparoscopic techniques has revolutionised urological practice. This necessitates a pneumoperitoneum (PNP) and the impact the PNP pressure has on post-operative outcomes is uncertain. During the currentCOVID-19 era guidance has suggested the utilisation of lower PNP pressures to mitigate the risk of intra-operative viral transmission. Review the current literature regarding the impact of pneumoperitoneum pressure, within the field of urology, on post-operative outcomes. A search of the PubMed, Medline and EMBASE databases was undertaken to identify studies that met the inclusion criteria. The Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines were adhered to. Ten studies, that included both randomised controlled trials and retrospective case series reviews, were identified that met the inclusion criteria. The effect of PNP pressure on outcomes following prostatectomy, live donor nephrectomy, partial nephrectomy and a variety of benign upper tract procedures were discussed. Low pressure PNP appears safe when compared to high pressure PNP, potentially reducing post-operative pain and rates of ileus. When compared to general surgery, there is a lack of quality evidence investigating the impact of PNP pressures on outcomes within urology. Low pressure PNP appears non-inferior to high pressure PNP. More research is required to validate this finding, particularly post-cystectomy and nephrectomy.Peer reviewe

    Exploring the key drivers of forest flammability in wet eucalypt forests using expert-derived conceptual models

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    © 2020, Springer Nature B.V. Context: Fire behaviour research has largely focused on dry ecosystems that burn frequently, with far less attention on wetter forests. Yet, the impacts of fire in wet forests can be high and therefore understanding the drivers of fire in these systems is vital. Objectives: We sought to identify and rank by importance the factors plausibly driving flammability in wet eucalypt forests, and describe relationships between them. In doing so, we formulated a set of research priorities. Methods: Conceptual models of forest flammability in wet eucalypt forests were elicited from 21 fire experts using a combination of elicitation techniques. Forest flammability was defined using fire occurrence and fireline intensity as measures of ignitability and heat release rate, respectively. Results: There were shared and divergent opinions about the drivers of flammability in wet eucalypt forests. Widely agreed factors were drought, dead fine fuel moisture content, weather and topography. These factors all influence the availability of biomass to burn, albeit their effects and interactions on various dimensions of flammability are poorly understood. Differences between the models related to lesser understood factors (e.g. live and coarse fuel moisture, plant traits, heatwaves) and the links between factors. Conclusions: By documenting alternative conceptual models, we made shared and divergent opinions explicit about flammability in wet forests. We identified four priority research areas: (1) quantifying drought and fuel moisture thresholds for fire occurrence and intensity, (2) modelling microclimate in dense vegetation and rugged terrain, (3) determining the attributes of live vegetation that influence forest flammability, (4) evaluating fire management strategies
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