41 research outputs found

    Monitoring rice agropractices in North Africa: a comparison of MODIS and Sentinel-1 results

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    Agro-monitoring systems need up-to-date information on where, when and how much a crop is cultivated, in particular in developing countries and for food security reasons. Such information can be derived from remote sensing imagery with fast revisiting cycles. In the past, only time series of optical moderate resolution data such as HVRR, SPOT-Vegetation and MODIS provided the necessary high temporal resolution for this kind of applications. These datasets have been successfully used for agro-monitoring activities and to perform retrospective and trend analysis. Due to their moderate to coarse spatial resolution (~ 250 – 1000 m) their applications are limited however to regional to continental scales. In this context, the advent of the Sentinel sensors opens new opportunities, since they provide time series of satellite imagery with decametric spatial resolution and revisit times of 5 days. Studies that fully exploit Sentinel imagery for crop monitoring are therefore needed to assess their potential contribution for i) performing high resolution crop-monitoring activities and, ii) extending time series of information derived from archive coarse resolution imagery with the aim of performing analyses of temporal trends over a reasonably long time span. This contribution presents a comparison of MODIS or Sentinel1 time series for detection (cultivated area and number of seasons) and seasonal dynamics’ analysis (sowing, harvesting and flowering dates) for irrigated rice cultivation in the Senegal River Valley (SRV)for the 2016 dry and wet rice seasons. MODIS time series analysis exploited the PhenoRice algorithm (Boschetti et al., 2017), a rule-based algorithm specifically designed for rice detection and seasonal dynamics monitoring and based on the use of time series of TERRA and AQUA 250 m resolution 16-day Composite Vegetation Indexes (MODIS products MOD13Q1 and MYD13Q1). The SAR data analysis was instead based on analysis of Sentinel-1A time series acquired over the study area from January to December 2016. In particular, the RICEscape software was used for analysing the SAR backscatter (0) temporal profiles both in the VV and in the VH polarization, to define a set of rules allowing to properly identify rice cultivated areas. The algorithm mostly exploits SAR data, although cloud free Landsat-8 Optical images were used to crosscheck and complement the information derived from SAR. This approach was applied to generate rice crop area and Start of Season (SOS) maps for both the dry (sowing in February – April) and the wet (sowing in September – November) rice seasons. Results showed a strong consistency between the thematic maps derived from the two data sources. We observed that, although the rice-classified area is rather different due to the large difference in spatial resolution, the main spatial patterns of estimated sowing dates and crop intensity are quite similar. A comparison between the average values of MODIS and SAR estimated dates after aggregation on a 2x2 km regular grid shows a strong correlation between the sowing dates derived from Sentinel-1 and MODIS data, for both the dry and the wet season of 2016. The comparability of MODIS and Sentinel results is encouraging for the development of innovative services for characterization and monitoring of crop systems. Such systems could in fact exploit both the sufficiently long MODIS time series to characterize the main characteristics of crop systems and their recent evolution, as well as the innovative Sentinel-1 time series for monitoring of present-day and future conditions

    pericardial patch as a palliative treatment in three dogs affected by unresectable cardiac tumor

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    Abstract This report is aimed at describing a pericardial patch for unresectable cardiac tumors as a palliative technique to prevent pleural effusion. Each dog underwent the same diagnostic protocol including a cardiological assessment, hematology and biochemistry profile, urinary test, abdominal and heart ultrasonography and chest radiographs. Computed tomography was always performed in order to exclude any potential metastatic lesions. All dogs underwent open pericardiectomy: the pericardium was opened and transposed on the mass according to its shape. Biopsy of the mass was always performed. Histopathological evaluation of the masses described two HAS and one chemodectoma. Chemotherapy protocol includes doxorubicin that was weekly administered. Dogs with HSA survived 65 and 85 days respectively without pleural effusion, while the dog with chemodectoma died after six months for reasons unrelated to the tumor. No evidence of pleural effusion was observed during the heart recheck, monthly performed. Pericardial patch is a potential choice as a palliative treatment for unresectable cardiac tumors. No pleural effusion was seen in three dogs affected by unresectable cardiac tumors

    Subtotal Epiglottectomy and Ablation of Unilateral Arytenoid Cartilage as Surgical Treatments for Grade III Laryngeal Collapse in Dogs

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    Stage III laryngeal collapse is defined as the collapse of the corniculate processes of the arytenoid cartilages and the destructuration of the dorsal portion of the rima glottidis. The primary cause is chronic upper airway obstruction, and the condition is often present in brachycephalic dogs. The treatment is still controversial; the patients are generally treated with a permanent tracheostomy. This article reports the authors’ experience with 16 dogs affected by stage III laryngeal collapse treated with subtotal epiglottectomy and the ablation of unilateral arytenoid cartilage. Before the surgery, all of the dogs underwent an effort test to classify the clinical severity of the disease and an endoscopic examination of the airways to determine the stage of severity of the laryngeal collapse. One month after surgery, the effort test was repeated in order to evaluate the clinical outcome. One year after surgery, the owners of 12 patients rated their dogs as follows: excellent in five cases, good in five cases, and fair in two cases. According to this pilot study, epiglottectomy associated with the photoablation of unilateral arytenoid cartilage increases airway flow, and thus may be considered a valid surgical procedure to treat dogs affected by grade III laryngeal collaps

    A Comparison of Times Taken for the Placement of the First portal and Complication Rates between the Veress Needle Technique and the Modified Hasson Technique in Canine Ovariectomy Laparoscopic Surgery

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    Minimally invasive surgery is increasingly being used in veterinary medicine. Laparoscopic procedures have several advantages compared with open surgery. These include the magnification of the field of surgery, reduced post-surgical pain and associated stress, reduced post-operative infection rates, and decreased hospitalization time. The establishment of a pneumoperitoneum is a critical step; however, this procedure can prolong the operation time, and most of the complications associated with laparoscopic surgery have been attributed to the insertion of devices into the abdominal cavity. Two main techniques have been employed to create pneumoperitoneum: the closed-entry method using the Veress needle and the open Hasson technique. The first portal is necessary to start insufflation and, subsequently, to realize the operative channel to insert the laparoscopic instruments into the abdomen. Many authors have compared the time necessary to create the first portal using different techniques in human medicine, but studies on this topic in veterinary medicine are lacking. In the veterinary medicine literature, complications associated with the creation of a pneumoperitoneum and the placement of ports include spleen, bowel, or bladder injuries; pneumothorax; and subcutaneous emphysema. The aim of the present study was to compare the times required for the placement of the first portal and the creation of pneumoperitoneum, and the rates of intraoperative complications using the Veress needle technique (VNT) and the open modified Hasson technique (MHT). The sample population comprised 30 female dogs who underwent laparoscopic ovariectomies. The dogs were randomly organized into two groups and two different entry techniques were used: Veress needle (VNT = group A) and the modified Hasson technique (MHT = group B). Complications related to abdominal entry were classified as major, in cases of organ perforation, and minor, in cases of subcutaneous emphysema and gas leakage. The VNT and MHT required 374.0 s and 242.9 s, respectively, for the placement of the first portal and for establishing pneumoperitoneum (p < 0.05). Their major complications rates were 20% and 0%, respectively (p < 0.05). Their minor complications rates were 20% and 35%, respectively (p < 0.05). No surgical procedures required laparotomy. The MHT was associated with a lower major complication rate and required less time to create the first portal, compared with the Veress needle technique

    Two-Port Laparoscopic Adrenalectomy in Dogs

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    SIMPLE SUMMARY: An adrenal mass represents the primary indication for adrenalectomy. Laparoscopic adrenalectomy is a minimally invasive surgical technique that minimizes pain and improves patient recovery. The traditional technique involves the use of a single or multiple port (three or four). The objective of the study was to evaluate the feasibility and complication rate of two-port laparoscopic adrenalectomy to remove adrenal masses smaller than 4 cm in diameter. In total, 16 dogs with adrenal masses were enrolled in the study and clinicopathologic data were harvested from the medical records. The dogs were placed in sternal recumbency with cushions positioned under the sternum and pubis to simulate the quadrupedal station and displace the abdominal viscera. In all cases, the procedures were feasible with two ports. In five cases, capsule rupture occurred, and all were adrenal gland carcinomas. ABSTRACT: The gold-standard treatment for functional tumors is adrenalectomy, and the procedure can be either open or laparoscopic. Laparoscopic adrenalectomy (LA) is a minimally invasive technique designated for small–medium-sized adrenal tumors without vascular invasion. LA is routinely performed using three or four ports with the patient in sternal or lateral recumbency. The aim of the study was to evaluate the feasibility of LA with two ports in order to reduce invasiveness and improve patient recovery. In total, 16 dogs with adrenal tumors were included in the study and the two-port technique was performed. Adrenalectomy was performed based on the presence of hypercortisolism in thirteen cases, whereas, in three cases, adrenalectomy was performed in the absence of evidence of cortisol production. Thirteen cases were carcinomas and three were adenomas of the adrenal gland; furthermore, twelve were on the left side and four were on the right side. Capsule rupture occurred in five cases. After performing the technique in all cases, no additional ports or laparotomy conversion occurred. Based on the authors’ experience, laparoscopic adrenalectomy can be performed with two ports
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