Nowadays, forest inventories are frequently carried out using a combination of field measurements and remote sensing data, often acquired with light detection and ranging (LiDAR) sensors. Several ...studies have investigated how three-dimensional laser scanning point clouds from different platforms can be used to acquire information traditionally collected with forest instruments, such as hypsometers and callipers to detect single-tree attributes like tree height and diameter at the breast height. The present study has tested the performances of the ZEB1 instrument, a type of hand-held mobile laser scanner, for single-tree attributes estimation in pure Castanea sativa Mill. stands cultivated for fruit production in Central Italy. In particular, the influence of walking scan path density on single-tree attributes estimation (number of trees, tree position, diameter at breast height, tree height, and crown base height) was investigated to test the efficiency of field measures. The point clouds were acquired by walking along straight lines drawn with different spacing: 10 and 15 m apart. A single-tree scan approach, which included walking with the instrument around each tree, was used as reference data. In order to evaluate the efficiency of the survey, the influence of the walking scan path was discussed in relation to the accuracy of single-tree attributes estimation, as well as the time and cost needed for data acquisition, pre-processing, and analysis. Our results show that the 10 m scan path provided the best results, with an omission error of 6%; the assessment of single-tree attributes was successful, with values of the coefficient of determination and the relative root mean square error similar to other studies. The 10 m scan path has also proved to decrease the costs by about €14 for data pre-processing, and a saving of time for data acquisition and data analysis of about 37 min compared to the reference data.
Abstract
One of many possible climate change effects in temperate areas is the increase of frequency and severity of windstorms; thus, fast and cost efficient new methods are needed to evaluate ...wind-induced damages in forests. We present a method for assessing windstorm damages in forest landscapes based on a two-stage sampling strategy using single-date, post-event airborne laser scanning (ALS) data. ALS data are used for delineating damaged forest stands and for an initial evaluation of the volume of fallen trees. The total volume of fallen trees is then estimated using a two-stage model-assisted approach, where variables from ALS are used as auxiliary information in the difference estimator. In the first stage, a sample of the delineated forest stands is selected, and in the second stage the within-stand damages are estimated by means of line intercept sampling (LIS). The proposed method produces maps of windthrown areas, estimates of forest damages in terms of the total volume of fallen trees, and the uncertainty of the estimates. A case study is presented for a large windstorm that struck the Tuscany Region of Italy the night of the 4th and the 5th of March 2015 and caused extensive damages to trees in both forest and urban areas. The pure field-based estimates from LIS and the ALS-based estimates of stand-level fallen wood were very similar. Our positive results demonstrate the utility of the single-date approach for a fast assessment of windthrow damages in forest stands which is especially useful when pre-event ALS data are not available.
To determine the prevalence, risk, and determinants of pressure ulcer risk in a large cohort of hospitalized patients.
A prospective cross-sectional study with data collection in January 2023.
...Registered nurses collected data from 798 patients admitted to 27 health care units of an Italian hospital. The pressure ulcer risk was assessed using the Braden scale. The presence of comorbidities was collected from clinical reports. Obesity was assessed according to international indicators (Body Mass Index). The receiver operating characteristic (ROC) curve was used to estimate the sensitivity and specificity of different Braden scores for identifying participants with pressure ulcers.
The prevalence of pressure ulcers was 9.5%, and 57.4% of the sample were at risk of developing pressure ulcers. The area under the ROC curve was 0.88. The best sensitivity and specificity were found for a Braden cutoff score of 15.5 (sensibility = 0.76; specificity = 0.85). The determinants of lower Braden scores were older age (p < 0.001), comorbidities (p < 0.001), wounds of other nature (p = 0.001), urinary incontinence (p < 0.001), fecal incontinence (p < 0.001), and urinary catheterization (p < 0.001).
Several demographic factors and specific clinical indicators have been identified as determinants of the risk of developing pressure ulcers, which are easily ascertainable by healthcare providers; thus, they may routinely complement the Braden Scale in the assessment of pressure ulcer risk in order to reinforce and accelerate clinical judgment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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