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101.
Wavelet analysis of MODIS time series to detect expansion and intensification of row-crop agriculture in Brazil 总被引:8,自引:0,他引:8
Gillian L. Galford John F. Mustard Aline Gendrin Carlos C. Cerri 《Remote sensing of environment》2008,112(2):576-587
Since 2000, the southwestern Brazilian Amazon has undergone a rapid transformation from natural vegetation and pastures to row-crop agricultural with the potential to affect regional biogeochemistry. The goals of this research are to assess wavelet algorithms applied to MODIS time series to determine expansion of row-crops and intensification of the number of crops grown. MODIS provides data from February 2000 to present, a period of agricultural expansion and intensification in the southwestern Brazilian Amazon. We have selected a study area near Comodoro, Mato Grosso because of the rapid growth of row-crop agriculture and availability of ground truth data of agricultural land-use history. We used a 90% power wavelet transform to create a wavelet-smoothed time series for five years of MODIS EVI data. From this wavelet-smoothed time series we determine characteristic phenology of single and double crops. We estimate that over 3200 km2 were converted from native vegetation and pasture to row-crop agriculture from 2000 to 2005 in our study area encompassing 40,000 km2. We observe an increase of 2000 km2 of agricultural intensification, where areas of single crops were converted to double crops during the study period. 相似文献
102.
BACKGROUND/AIMS: The purpose of this study was to describe the echographic features of Ascaris lumbricoides invasion of the alimentary tract, biliary system, liver and pancreas. METHODOLOGY: We studied 38 patients with roundworm heavy infection whose diagnosis were primarily supported by ultrasonographic examination. RESULTS: Thirty-seven patients were admitted with the following clinical complications: bowel obstruction, intra and extrahepatic dilatation, acute cholecystitis, intrahepatic abscess, acute appendicitis, subphrenic collection and acute pancreatitis. Ultrasound scanning was able to recognize in 30 cases the echogenic, nonshadowing images of the worms as single or multiple strips; in 8 cases, coiled structures and amorphous material were detected. The "inner tube" sign was considered as the most specific one. In two cases the roundworms were displayed within the stomach, a curious finding, up to now never reported in medical literature. CONCLUSIONS: Real-time sonography represents an efficient, reliable and non-invasive diagnostic approach for hepatobiliary, enteric and pancreatic ascariasis. 相似文献
103.
Clara Bernardelli Eloisa Chiaramonte Silvia Ancona Silvia M. Sirchia Amilcare Cerri Elena Lesma 《International journal of molecular sciences》2022,23(17)
Cutaneous lesions are one of the hallmarks of tuberous sclerosis complex (TSC), a genetic disease in which mTOR is hyperactivated due to the lack of hamartin or tuberin. To date, novel pharmacological treatments for TSC cutaneous lesions that are benign but still have an impact on a patient’s life are needed, because neither surgery nor rapamycin administration prevents their recurrence. Here, we demonstrated that primary TSC2-/meth cells that do not express tuberin for an epigenetic event caused cutaneous lesions and follicular neogenesis when they were subcutaneously injected in nude mice. Tuberin-null cells localized in the hair bulbs and alongside mature hairs, where high phosphorylation of S6 and Erk indicated mTOR hyperactivation. Interestingly, 5-azacytidine treatment reduced hair follicles, indicating that chromatin remodeling agents might be effective on TSC lesions in which cells lack tuberin for an epigenetic event. Moreover, we demonstrated that the primary TSC2-/meth cells had metastatic capability: when subcutaneously injected, they reached the bloodstream and lymphatics and invaded the lungs, causing the enlargement of the alveolar walls. The capability of TSC2-/meth cells to survive and migrate in vivo makes our mouse model ideal to follow the progression of the disease and test potential pharmacological treatments in a time-dependent manner. 相似文献
104.
S. Borchardt C.M. Tippenhauer J.-L. Plenio A. Bartel A.M.L. Madureira R.L.A. Cerri W. Heuwieser 《Journal of dairy science》2021,104(8):9195-9204
The objective of this observational study was to evaluate the association of estrous expression within 40 days in milk (DIM) using a neck-mounted automated activity monitor (Heatime Pro; SCR Engineers Ltd.) with reproductive performance in lactating Holstein cows. A total of 2,077 cows (614 primiparous cows and 1,463 multiparous cows) from 5 commercial dairy farms were included in the statistical analyses. Activity data from the first 7 d after calving were excluded. An estrus event was defined as an activity change index ≥35 for more than 2 h. Cows were classified according to the number of estrus events from d 7 until d 40 postpartum into 3 categories: (1) no estrus event (Estrus0); (2) one estrus event (Estrus1), and (3) 2 or more estrus events (Estrus2). Generalized linear mixed models were used to analyze continuous and categorical data. Shared frailty models were used for time to event data. Overall, 52.7% of cows had no estrus event detected by an automated activity monitor system from d 7 until d 40 postpartum. Herd level prevalence of Estrus0 ranged from 37.5 to 58.4%. Estrous expression from d 7 until d 40 postpartum affected estrous duration and estrous intensity at first artificial insemination (AI). Cows in Estrus0 had the shortest duration (13.2 ± 0.33 h) compared with cows in Estrus1 (13.8 ± 0.36 h) and Estrus2 (14.8 ± 0.41 h). Cows in Estrus2 had a longer estrous duration at first postpartum AI compared with cows in Estrus1. Among Estrus0 cows, 46.2% had an estrus event with high intensity at first postpartum AI. Among cows in Estrus1 and Estrus2, 50.8 and 53.8% had an estrus event with high intensity at first postpartum AI, respectively. There was a significant difference between Estrus2 and Estrus0 and a tendency between Estrus0 and Estrus1. There was no difference between Estrus1 and Estrus2. For Estrus0, Estrus1, and Estrus2 cows, pregnancy per AI was 29.4, 30.9, and 37.8%, respectively. There was a significant difference between Estrus0 and Estrus2 and Estrus1 and Estrus2. There was no difference between Estrus0 and Estrus1. Estrous expression from d 7 until d 40 postpartum affected time to first AI and time to pregnancy. Compared with Estrus0 cows, cows in Estrus1 [hazard risk (HR) = 1.74] and Estrus2 (HR = 1.77) had an increased hazard of being inseminated within 100 DIM. There was no difference between Estrus1 and Estrus2. Median DIM to first AI were 70, 59, and 58 for cows in Estrus0, Estrus1, and Estrus2, respectively. Compared with Estrus0 cows, cows in Estrus1 (HR = 1.28) and Estrus2 (HR = 1.33) had an increased hazard of becoming pregnant within 200 DIM. There was no difference between Estrus1 and Estrus2. Median DIM to pregnancy were 127, 112, and 103 for Estrus0 cows, Estrus1 and Estrus2, respectively. In conclusion, cows with no estrous expression from 7 to 40 DIM had reduced estrous expression at first AI and inferior reproductive performance compared with cows that displayed estrous activity. 相似文献
105.
Claudio Giuliano Miriam Francavilla Gerardo Ongari Alessandro Petese Cristina Ghezzi Nora Rossini Fabio Blandini Silvia Cerri 《International journal of molecular sciences》2021,22(16)
Parkinson’s disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons in the Substantia Nigra pars compacta, leading to classical PD motor symptoms. Current therapies are purely symptomatic and do not modify disease progression. Cannabidiol (CBD), one of the main phytocannabinoids identified in Cannabis Sativa, which exhibits a large spectrum of therapeutic properties, including anti-inflammatory and antioxidant effects, suggesting its potential as disease-modifying agent for PD. The aim of this study was to evaluate the effects of chronic treatment with CBD (10 mg/kg, i.p.) on PD-associated neurodegenerative and neuroinflammatory processes, and motor deficits in the 6-hydroxydopamine model. Moreover, we investigated the potential mechanisms by which CBD exerted its effects in this model. CBD-treated animals showed a reduction of nigrostriatal degeneration accompanied by a damping of the neuroinflammatory response and an improvement of motor performance. In particular, CBD exhibits a preferential action on astrocytes and activates the astrocytic transient receptor potential vanilloid 1 (TRPV1), thus, enhancing the endogenous neuroprotective response of ciliary neurotrophic factor (CNTF). These results overall support the potential therapeutic utility of CBD in PD, as both neuroprotective and symptomatic agent. 相似文献
106.
S. Biasotti A. Cerri M. Aono A. Ben Hamza V. Garro A. Giachetti D. Giorgi A. Godil C. Li C. Sanada M. Spagnuolo A. Tatsuma S. Velasco-Forero 《The Visual computer》2016,32(2):217-241
This paper presents a comparative study of six methods for the retrieval and classification of textured 3D models, which have been selected as representative of the state of the art. To better analyse and control how methods deal with specific classes of geometric and texture deformations, we built a collection of 572 synthetic textured mesh models, in which each class includes multiple texture and geometric modifications of a small set of null models. Results show a challenging, yet lively, scenario and also reveal interesting insights into how to deal with texture information according to different approaches, possibly working in the CIELab as well as in modifications of the RGB colour space. 相似文献
107.
108.
Cerri G. Chiarandini S. Costantini S. De Leo R. Mariani Primiani V. Russo P. 《Electromagnetic Compatibility, IEEE Transactions on》2002,44(1):139-147
The problem of the evaluation of the electromagnetic (EM) field radiated by an electrostatic discharge (ESD) current is examined, and an efficient numerical code for the evaluation of the radiated field is developed. The considered radiating structures, a monopole and a loop, are analyzed in the time domain using a modified electric field integral equation (EFIE). A modification of the integral equation was introduced in order to take into account the reflection of the incident pulse at the input terminals of the antenna, when fed by a transmission line. The reflected wave is very significant and its evaluation is fundamental for the comparison of theoretical and experimental data. The ESD current flowing along the wire is determined using the method of moments in time domain (MoMTD). From the knowledge of the transient current, the radiated EM field is evaluated by a standard technique. The developed model is the first stage of a project for the characterization of the measurement environment during an ESD test. All numerical results are validated by measurements and good agreement is shown 相似文献
109.
A method for the analysis of the electromagnetic field inside metallic enclosures with apertures is presented. The model is based on a time domain hybrid approach method, characterised by the combination of the finite difference in time domain (FDTD), and the method of moments in time domain (MoMTD) that solves a magnetic field integral equation (MFIE). 相似文献
110.
N. Chapinal M.A.G. von Keyserlingk R.L.A. Cerri K. Ito S.J. LeBlanc D.M. Weary 《Journal of dairy science》2013
The objectives of this study were to describe herd-level reproductive outcomes and their associations with the prevalence of lameness, hock injuries and knee injuries in freestall dairy herds in the northeastern United States. Five reproductive outcomes (calving to conception interval, CCI; calving interval, CI; conception risk at the first artificial insemination, CR1; insemination rate, IR; and pregnancy rate, PR) were measured from Dairy Comp 305 (Valley Agricultural Software, Tulare, CA) for a 12-mo period for all multiparous cows in each of the 53 herds assessed. The prevalence of lameness, hock injuries, and knee injuries was assessed in 1 high-producing group. The means (± standard deviation) for the 5 reproductive outcomes were as follows: CCI = 128 ± 10 d, CI = 404 ± 10 d, CR1 = 36 ± 5%, IR = 60 ± 7%, and PR = 20 ± 3%. The average prevalence of clinical lameness, hock injuries, and knee injuries were 45 ± 20%, 58 ± 31%, and 16 ± 15%, respectively. Univariable associations between the reproductive outcomes and the prevalence of lameness and leg injuries were tested and significant predictors were submitted to a model that controlled for the confounding effects of herd size, 305-d mature equivalent milk production of the high-producing group, and use of deep bedding. A higher prevalence of lameness was associated with poorer reproductive performance, although the relationships were weak: herds with a higher prevalence of lameness had longer average CCI (slope estimate = 0.16 ± 0.07; R2 = 0.09) and CI (slope estimate = 0.14 ± 0.07; R2 = 0.07). These results indicate that management to reduce lameness may improve reproductive performance. 相似文献