Abstract
Mergers are thought to be a fundamental channel for galaxy growth, perturbing the gas dynamics and the magnetic fields (
B
-fields) in the interstellar medium (ISM). However, the mechanisms ...that amplify and dissipate
B
-fields during a merger remain unclear. We characterize the morphology of the ordered
B
-fields in the multiphase ISM of the closest merger of two spiral galaxies, the Antennae galaxies. We compare the inferred
B
-fields using 154
μ
m thermal dust and 11 cm radio synchrotron emission polarimetric observations. We find that the 154
μ
m
B
-fields are more ordered across the Antennae galaxies than the 11 cm
B
-fields. The turbulent-to-ordered 154
μ
m
B
-field increases at the galaxy cores and star-forming regions. The relic spiral arm has an ordered spiral 154
μ
m
B
-field, while the 11 cm
B
-field is radial. The 154
μ
m
B
-field may be dominated by turbulent dynamos with high
12
CO(1–0) velocity dispersion driven by star-forming regions, while the 11 cm
B
-field is cospatial with high H
i
velocity dispersion driven by galaxy interaction. This result shows the dissociation between the warm gas mainly disturbed by the merger, and the dense gas still following the dynamics of the relic spiral arm. We find a ∼8.9 kpc scale ordered
B
-field connecting the two galaxies. The base of the tidal tail is cospatial with the H
i
and
12
CO(1–0) emission and has compressed and/or sheared 154
μ
m and 11 cm
B
-fields driven by the merger. We suggest that amplified
B
-fields, with respect to the rest of the system and other spiral galaxies, may be supporting the gas flow between both galaxies and the tidal tail.
The leaf area index (LAI) is defined as the one-side leaf area per unit ground area, and is probably the most widely used index to characterize grapevine vigor. However, LAI varies spatially within ...vineyard plots. Mapping and quantifying this variability is very important for improving management decisions and agricultural practices. In this study, a mobile terrestrial laser scanner (MTLS) was used to map the LAI of a vineyard, and then to examine how different scanning methods (on-the-go or discontinuous systematic sampling) may affect the reliability of the resulting raster maps. The use of the MTLS allows calculating the enveloping vegetative area of the canopy, which is the sum of the leaf wall areas for both sides of the row (excluding gaps) and the projected upper area. Obtaining the enveloping areas requires scanning from both sides one meter length section along the row at each systematic sampling point. By converting the enveloping areas into LAI values, a raster map of the latter can be obtained by spatial interpolation (kriging). However, the user can opt for scanning on-the-go in a continuous way and compute 1-m LAI values along the rows, or instead, perform the scanning at discontinuous systematic sampling within the plot. An analysis of correlation between maps indicated that MTLS can be used discontinuously in specific sampling sections separated by up to 15 m along the rows. This capability significantly reduces the amount of data to be acquired at field level, the data storage capacity and the processing power of computers.
In this work, a LIDAR-based 3D Dynamic Measurement System is presented and evaluated for the geometric characterization of tree crops. Using this measurement system, trees were scanned from two ...opposing sides to obtain two three-dimensional point clouds. After registration of the point clouds, a simple and easily obtainable parameter is the number of impacts received by the scanned vegetation. The work in this study is based on the hypothesis of the existence of a linear relationship between the number of impacts of the LIDAR sensor laser beam on the vegetation and the tree leaf area. Tests performed under laboratory conditions using an ornamental tree and, subsequently, in a pear tree orchard demonstrate the correct operation of the measurement system presented in this paper. The results from both the laboratory and field tests confirm the initial hypothesis and the 3D Dynamic Measurement System is validated in field operation. This opens the door to new lines of research centred on the geometric characterization of tree crops in the field of agriculture and, more specifically, in precision fruit growing.
Aim:We aim to describe and evaluate a new model for distance experiential learningin order to help reduce the transmission risk among professionals envolved in education activities.Materials and ...Methods:In April 2020, in partnership with our hospital’s Emergency Department Educational Leadership, Valdecilla Virtual Hospital tested and introduced an experiential distance learning model. Professionals wanted to engage from their homes without having to travel to a simulation facility.Results:Between July 1 and 22, 2020 we ran seven courses following this new model of course. Each one consisted of a two-hour session on two consecutive days. There were 44 participants whose ages ranged from 26 to 53 years (average=40), 62% identified as female, and 68% reported working at the emergency department, 19% at the cardiology unit, 7% in primary care, and 5% in internal medicine. We evaluated the content validity, feasibility and acceptability of the model. The results of an anonymous survey filled in at the end of the course showed they considered the distance training model as realistic (92%), easy to use (95%), well-organized (94%), an engaging educational tool (94%), and desirable for practising in the future (94%).Conclusion:These results may encourage the educational community to develop more programs using this new approach of “taking care of patients from a distance” not only during a pandemic, but also on a regular basis. We think this model can achieve positive results using distance clinical simulation combining their traditional simulation technology to address the training needs of their healthcare organization.
Growth alterations have been described in patients operated on for oral clefts. The purpose of this work was to analyze the craniofacial and palate morphology and dimensions of young adults operated ...on for oral clefts in early childhood in Spain. Eighty-three patients from eight different hospitals were divided into four groups based on their type of cleft: cleft lip (CL, n = 6), unilateral cleft lip and palate (UCLP, n = 37), bilateral cleft lip and palate (BCLP, n = 16), and cleft palate only (CPO, n = 24). A control group was formed of 71 individuals. Three-dimensional (3D) digital models were obtained from all groups with an intraoral scanner, together with cephalometries and frontal, lateral, and submental facial photographs. Measurements were obtained and analyzed statistically. Our results showed craniofacial alterations in the BCLP, UCLP, and CPO groups with an influence on the palate, maxilla, and mandible and a direct impact on facial appearance. This effect was more severe in the BCLP group. Measurements in the CL group were similar to those in the control group. Cleft characteristics and cleft type seem to be the main determining factors of long-term craniofacial growth alterations in these patients. Prospective research is needed to clearly delineate the effects of different treatments on the craniofacial appearance of adult cleft patients.
This paper presents the use of a terrestrial light detection and ranging (LiDAR) system to scan the vegetation of tree crops to estimate the so-called pixelated leaf wall area (PLWA). Scanning rows ...laterally and considering only the half-canopy vegetation to the line of the trunks, PLWA refers to the vertical projected area without gaps detected by LiDAR. As defined, PLWA may be different depending on the side from which the LiDAR is applied. The system is completed by a real-time kinematic global positioning system (RTK-GPS) sensor and an inertial measurement unit (IMU) sensor for positioning. At the end, a total leaf wall area (LWA) is computed and assigned to the X, Y position of each vertical scan. The final value of the area depends on the distance between two consecutive scans (or horizontal resolution), as well as the number of intercepted points within each scan, since PLWA is only computed when the laser beam detects vegetation. To verify system performance, tests were conducted related to the georeferencing task and synchronization problems between GPS time and central processing unit (CPU) time. Despite this, the overall accuracy of the system is generally acceptable. The Leaf Area Index (LAI) can then be estimated using PLWA as an explanatory variable in appropriate linear regression models.
Hemobilia is a rare cause of upper gastrointestinal bleeding (UGIB). It is commonly iatrogenic, and is more rarely caused by tumors, lithiasis, and inflammatory or vascular disease. We describe a ...case of cystic artery pseudoaneurysm, which caused acute pancreatitis as an unusual complication.
A geostatistical methodology is presented to optimise the dosage of plant protection products (PPP) in vineyards with spatial variability. Sprayers are commonly used in viticulture to apply a ...constant volume rate per unit ground area (l ha−1). This can be a problem in vineyard plots with remarkable spatial variability in vine vigour, being necessary guiding winegrowers through a decision-making tool to determine an appropriate uniform volume rate. The leaf area index (LAI), measured by a terrestrial LiDAR scanner at high spatial resolution along crop rows, can be used to determine the optimum volume application rate. The proposed method is based on obtaining different probability maps of LAI by applying an indicator kriging to the original LAI data. As a result, this method allows winegrowers to i) map and locate areas within the plot that, within a given confidence level (70% or 90%), exceed or do not exceed different values (percentiles) of the original LAI, and ii) set the LAI and the corresponding volume rate seeking, for example, to balance the probability (risk) of areas with lower and higher doses than required. In more conservative protection strategies, the method also allows farmers to set the values of LAI and volume rate that greatly minimise the probability of vulnerable areas being underdosed.
•LAI probability maps to optimise spatially variable PPP application in vineyards.•Method defines reference LAI and allows corresponding volume rate to be set.•Risk of overdosed/underdosed areas within the plot needs to be balanced.•65th - 80th percentile of original LAI values reference used for dose expressions.•This method can minimise the risk of underdosing.
Summary Healthcare delivery has traditionally been structured on the performance of expert, individual practitioners, reflecting the fundamental notion of specialization. In the rapidly changing ...healthcare industry, this approach is evolving. The increasing amount of clinical knowledge and technological advances, in combination with aging populations, are shaping organizations. Interdisciplinary healthcare teams have become the new model for patient care delivery. In this article we review why Virtual Hospitals are being proposed as a new training model paradigm. Virtual Hospitals replicate substantial aspects of the work environment, and allow simulated clinical immersion. They offer opportunities to reflect on how organizations work, learn how to be more effective when working with others, and acquire the tools that make the differences between an average and an excellent provider.
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