Abstract
Cloud features above the Pierre Auger Observatory (Mendoza Province, Argentina) significantly affect the reconstruction of Extensive Air Showers. In this work, we present seasonal variations ...of cloud-base height, cloud coverage, and correlation between different sites using the information of elastic multiangle lidar data. This system locates the presence of clouds by measuring the spikes in the backscattered photons detected in the direction of the sweep performed during each lidar scan, outside the field of view (FOV) of the fluorescence detectors. Horizontal homogeneity should be assumed to translate these results to the full array. This ansatz is verified by a set of dedicated horizontal lidar shots performed for a few seconds every hour inside the FOV of the fluorescence detectors. Here we present the results for the period 2007 to 2016, using all the continuous lidar scans available in the lidar database. The analysis algorithm used for cloud retrieval has been upgraded and is based on a different concept than the previous one. How cloud parameters vary across seasons is investigated, and conclusions about cloud homogeneity across the Pierre Auger array are given.
The Indurometer is a tool designed by the Flinders Biomedical Engineering Department to replace the Tissue Tonometer. It measures the resistance to an applied force to quantify the amount of fibrosis ...present within the epifascial compartment of tissue. The aim of the study was to compare the current model of the Indurometer with the Tonometer to determine the level of variability and repeatability between the two devices and how the variability differs when compared to an individual's ISL stage.
Data were gathered on a total of 180 participants with unilateral arm lymphedema as part of an international multicenter trial. For each participant three repeat measurements were obtained with the Indurometer and Tonometer at the anterior mid forearm and anterior mid upper arm. The Indurometer gave lower measurement values than the Tonometer. The Tonometer was found to be less variable than the Indurometer when measurements were taken from the anterior mid upper arm and the anterior mid forearm site. The Tonometer values were significantly less variable than the Indurometer values in ISL stages 1 and 2. No significant variability was found in stage 3.
The Indurometer is easier to use as compared to the Tonometer. Modification of the Indurometer needs to take place in order to improve its variability before it can be considered as a replacement for the Tonometer in the assessment of lymphedema. The lack of understanding of the ISL classification system is a significant issue.
Total ozone column (TOC) measurements through the Ozone Monitoring Instrument (OMI/NASA EOSAura) are compared with ground-based observations made using Dobson and SAOZ instruments for the period ...2004–2019 and 2008–02/2020, respectively. The OMI data were inverted using the Differential Optical Absorption Spectroscopy algorithm (overpass OMI-DOAS). The four ground-based sites used for the analysis are located in subpolar and subtropical latitudes spanning from 34°S to 54°S in the Southern Hemisphere, in the Argentine cities of Buenos Aires (34.58°S, 58.36°W; 25 m a.s.l.), Comodoro Rivadavia (45.86°S, 67.50°W; 46 m a.s.l.), Río Gallegos (51.60°S, 69.30°W; 72 m a.s.l.) and Ushuaia (54.80°S, 68.30°W; 14 m a.s.l.). The linear regression analyzes showed correlation values greater than 0.90 for all sites. The OMI measurements revealed an overestimation of less than 4 % with respect to the Dobson instruments, while the comparison with the SAOZ instrument presented a very low underestimation of less than 1 %.
Lymphoedema is a chronic progressive condition often producing significant morbidity. An in-depth understanding of an individual's lymphatic architecture is valuable both in the understanding of ...underlying pathology and for targeting and tailoring treatment. Severe lower limb injuries resulting in extensive loss of soft tissue require transposition of a flap consisting of muscle and/or soft tissue to close the defect. These patients are at risk of lymphoedema and little is known about lymphatic regeneration within the flap. Indocyanine green (ICG), a water-soluble dye, has proven useful for the imaging of lymphatic vessels. When injected into superficial tissues it binds to plasma proteins in lymph. By exposing the dye to specific wavelengths of light, ICG fluoresces with near-infrared light. Skin is relatively transparent to ICG fluorescence, enabling the visualization and characterization of superficial lymphatic vessels. An ICG fluorescence lymphatic vessel imager was manufactured to excite ICG and visualize real-time fluorescence as it travels through the lymphatic vessels. Animal studies showed successful ICG excitation and detection using this imager. Clinically, the imager has assisted researchers to visualize otherwise hidden superficial lymphatic pathways in patients postflap surgery. Preliminary results suggest superficial lymphatic vessels do not redevelop in muscle flaps.
At the end of August 2009, a biomass burning aerosol intrusion event was detected at the Laser and Applications Research Center, CEILAP (CITEFA-CONICET) (34.5° S – 58.5° W) at Villa Martelli, in ...Buenos Aires, Argentina. This center has a sunphotometer from the AERONET-NASA global network, UV solar radiation sensors, a meteorological station and an aerosol lidar system. The aerosol origin was determined by means of back-trajectories and satellite images. This work studies the aerosol air mass optical characterization and their effect in UV solar radiation.
This work studies multiwavelength lidar node operation requirements to operate in a regional aerosol monitoring network. Some of the parameters taken into account are simplicity and robustness of the ...system in continuous and remote operation conditions. Sub-system modularity and accessibility is also contemplated. A numerical simulation is performed on a synthetic atmospheric signal to analyze the behaviour of this system in a) the visible (532 nm) and infrared (1064 nm) spectral regions; b) the main atmospheric compound Raman spectral region (nitrogen, oxygen water vapor). Adding depolarization channels in the 532 nm spectral region is also contemplated.
This study investigates the influence of the 2015 Calbuco eruption (41.2∘ S, 72.4∘ W; Chile) on the total columnar aerosol optical properties over the Southern Hemisphere. The well-known technic of ...sun photometry was applied for the investigation of the transport and spatio-temporal evolution of the optical properties of the volcanic plume. The CIMEL sun photometer measurements performed at six South American and three African sites were statistically analysed. This study involves the use of the satellite observations and a back-trajectory model. The passage of the Calbuco plume is statistically detectable in the aerosol optical depth (AOD) observations obtained from sun photometer and MODIS observations. This statistical detection confirms that the majority of the plume was transported over the northeastern parts of South America and reached the South African region 1 week after the eruption. The plume impacted the southern parts of South America to a lesser extent. The highest AOD anomalies were observed over the northeastern parts of South America. Over the South African sites, the AOD anomalies induced by the spread of the plume were quite homogeneously distributed between the east and west coasts. The optical characteristics of the plume near the source region were consistent with an ash-bearing plume. Conversely, sites further from the Calbuco volcano were influenced by ash-free plume. The optical properties discussed in this paper will be used as inputs for numerical models for further investigation of the ageing of the Calbuco plume in a forthcoming study.
The purpose of this study was to assess the value of measuring parathormone levels in percutaneous needle aspirates of suspicious cervical lesions in patients with hyperparathyroidism to confirm ...whether the lesion represents abnormal parathyroid tissue.
The study group consisted of 66 patients with hyperparathyroidism in whom 80 cervical lesions were aspirated and levels of parathormone in the aspirates were measured. CT guidance was used for two patients and sonographic guidance for the remainder. The lesions selected for aspiration were demonstrated on either sonography or CT and had either an unusual position (separate from the thyroid gland or were intrathyroidal) or configuration (irregular shape or atypical heterogeneous sonographic texture). In 15 patients, an indeterminate, posteriorly located intrathyroidal mass was detected and felt most likely to represent a thyroid nodule by sonographic criteria. These masses were aspirated to rule out atypical parathyroid adenomas. In patients who had been previously explored for hyperparathyroidism and presented with persistent or recurrent hypercalcemia, all indeterminate, cervical, potentially parathyroid masses were aspirated for parathormone determination. The level of parathormone in each aspirate was measured by using an immunoradiometric assay.
Levels of parathormone were increased in the aspirates in 37 of the 45 patients in whom sonography showed classic lesions suggestive of parathyroid adenoma. This included the 25 patients who had previously undergone exploratory surgery. At surgery, all 37 had parathyroid adenomas in the indicated locations, for a specificity of 100%. In six patients, the results of the aspiration were false-negative. Parathyroid adenomas were suspected on sonograms and confirmed at surgery, but no parathormone was detected in the aspirate. Results of aspiration of indeterminate lesions were true-negative in two patients who had both characteristic and indeterminate lesions on sonography and in the 15 patients who had indeterminate lesions that were felt to be of thyroid origin. Aspirates contained no parathormone, and surgical findings confirmed the lesions were not of parathyroid origin.
Our results show that increased levels of parathormone in percutaneous needle aspirates of cervical masses in patients with hyperparathyroidism confirm the mass is a parathyroid adenoma. Although absence or low levels of parathormone in the aspirates usually excludes a parathyroid adenoma, this is not absolute as sometimes the needle may miss the mass, rendering the parathormone value invalid (false-negative).
Sphincter of Oddi manometry is the "gold standard" to evaluate the ductal anatomy of patients with suspected sphincter of Oddi dysfunction. During such procedure it can be unclear which duct is being ...investigated without radiographs. Bilirubin and other pigments in bile strongly absorb blue light, whereas pancreatic fluid is clear and does not absorb blue light. The bio-sensor system incorporates fibre-optic technology to measure blue light absorbance in the ducts. Bench tests and animal tests were conducted utilising possums. In bench and animal experiments the bio-sensor correctly discriminated between bile and pancreatic juice, based on the absorbance of blue light. The mean absorbance of the bile was 3.57+/-1.74 and that of the pancreatic duct fluid was 0.53+/-0.34 (P<0.01) in the animal models. The optical sensing system could be incorporated into a manometry catheter to aid sphincter of Oddi manometry shortening procedure time and reduce radiography exposure.
PDF
