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Setting the optimal length to be scanned in rows of vines by using mobile terrestrial laser scanners
Mapping the leaf area index (LAI) by using mobile terrestrial laser scanners (MTLS) is of significance for viticulture. LAI is related to plant vigour and foliar development being an important parameter for many agricultural practices. Since it may present spatial variability within vineyards, it is very interesting monitoring it in an objective repeatable way. Considering the possibility of using on-the-go sensors such as MTLS within an agricultural plot, it is necessary to set a proper length of the row to be scanned at each sample point for a reliable operation of the scanner. Three different row length sections of 0.5, 1, and 2 m have been tested. Data analysis has shown that models required to estimate LAI differ significantly depending on the scanned length of the row; the model required to estimate LAI for short sections (0.5 m) is different from that required for longer sections (1 and 2 m). Of the two models obtained, we recommend using MTLS for scanning row length sections of 1 m because the practical use of the sensor in the field is simplified without compromising the results (there is little variation in the model when the row length section changes from 1 to 2 m). In addition, a sufficient number of sampling points is obtained to support a map of the LAI. Linear regression models using as explanatory variable the tree area index, obtained from the data provided by the scanner, are used to estimate the LAI. 相似文献
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Martín-Pérez M Fernández-Borrás J Ibarz A Felip O Gutiérrez J Blasco J 《Journal of agricultural and food chemistry》2011,59(18):10261-10270
There are few traceability systems other than genetic markers capable of distinguishing between sea products of different origin and quality. Here, we address the potential of stable isotopes combined with metabolic and growth parameters as a discriminatory tool for the selection of fish seeds with high growth capacity. For this purpose, sea bream fingerlings produced in three hatcheries (Spanish Mediterranean coast, MC; Cantabrian coast, CC; and South-Iberian Atlantic coast, AC) were subjected to isotopic analysis (δ15N and δ13C), and indices of growth (RNA and DNA) and energy metabolism [cytochrome-c-oxidase (COX) and citrate synthase (CS) activities] were calculated. These analyses were performed prior to and after a "homogenization" period of 35 days under identical rearing conditions. After this period, fingerlings were discriminated between hatcheries, with isotopic measures (especially δ15N), metabolic parameters (COX and CS), and proximal composition (fat content) in muscle providing the highest discriminatory capacity. Therefore, particular rearing conditions and/or genetic divergence between hatcheries, affecting the growth capacity of fingerlings, are defined mainly by the isotopic imprint. Moreover, the muscle isotopic signature is a more suitable indicator than whole fish for discrimination purposes. 相似文献
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Jaume Arnó Alexandre Escolà Josep M. Vallès Jordi Llorens Ricardo Sanz Joan Masip Jordi Palacín Joan R. Rosell-Polo 《Precision Agriculture》2013,14(3):290-306
Estimation of grapevine vigour using mobile proximal sensors can provide an indirect method for determining grape yield and quality. Of the various indexes related to the characteristics of grapevine foliage, the leaf area index (LAI) is probably the most widely used in viticulture. To assess the feasibility of using light detection and ranging (LiDAR) sensors for predicting the LAI, several field trials were performed using a tractor-mounted LiDAR system. This system measured the crop in a transverse direction along the rows of vines and geometric and structural parameters were computed. The parameters evaluated were the height of the vines (H), the cross-sectional area (A), the canopy volume (V) and the tree area index (TAI). This last parameter was formulated as the ratio of the crop estimated area per unit ground area, using a local Poisson distribution to approximate the laser beam transmission probability within vines. In order to compare the calculated indexes with the actual values of LAI, the scanned vines were defoliated to obtain LAI values for different row sections. Linear regression analysis showed a good correlation (R 2 = 0.81) between canopy volume and the measured values of LAI for 1 m long sections. Nevertheless, the best estimation of the LAI was given by the TAI (R 2 = 0.92) for the same length, confirming LiDAR sensors as an interesting option for foliage characterization of grapevines. However, current limitations exist related to the complexity of data process and to the need to accumulate a sufficient number of scans to adequately estimate the LAI. 相似文献
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Jaume Gardela Mateo Ruiz‐Conca Manuel lvarez‐Rodríguez Teresa Mogas Manel Lpez‐Bjar 《Reproduction in domestic animals》2019,54(Z4):82-85
The aim of this study was to induce the cold‐inducible RNA‐binding protein (CIRBP) expression on cumulus–oocyte complexes (COCs) through exposure to a sub‐lethal cold shock and determine the effects of hypothermic temperatures during the in vitro maturation of bovine oocytes. Nuclear maturation, cortical granule redistribution and identification of cold‐inducible RNA‐binding protein (CIRBP) were assessed after 24 hr of in vitro maturation of control (38.5°C) and cold‐stressed oocytes (33.5°C). The presence of CIRBP was assessed by Western blot in COCs or denuded oocytes and their respective cumulus cells. Based on the odds ratio, cold‐stressed oocytes presented higher abnormal cytoplasmic distribution of cortical granules and nuclear maturation than the control group. Although CIRBP was detected in both control and cold‐stressed groups, cold‐stressed COCs had 2.17 times more expression of CIRBP than control COCs. However, when denuded oocytes and cumulus cells were assessed separately, CIRBP only was detected in cumulus cells in both groups. In conclusion, cold shock induced CIRBP expression, but it negatively affected nuclear maturation and cortical granule distribution of bovine oocytes. Moreover, the expression of CIRBP was only identified in cumulus cells but not in oocytes. 相似文献
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In order to study the potential use of microfauna as an indicator of effluent quality and operational parameters in an activated sludge system for treating piggery wastewater, an experimental sequencing batch reactor was set up and evaluated by biological and physical–chemical analyses for 12 months. Results show that microfauna (and specifically ciliate protozoa) are a good parameter for assessing effluent quality in terms of both chemical oxygen demand (COD) and ammonia and for assessing the organic and nitrogen load of the system. Specifically, the abundance of ciliates decreases from 20,000 individuals·mL?1 to ca. 2,500 individuals·mL?1 and from ca. 10,000 individuals mL?1 to ca. 200 individuals mL?1 when effluent concentration is between 550 and 750 mg L?1 and above 100 mg L?1 to the COD and ammonia concentrations, respectively. Furthermore, microfauna abundance is reduced from ca. 18,000 individuals mL?1 (organic load between 0.1 and 0.2 mg COD mg total suspended solids (TSS)?1 day?1) to ca. 500 individuals mL?1 (organic load between 0.3 and 04 mg COD mg TSS?1 day?1). Microfauna abundance also decreases as nitrogen loading increases. Nitrogen loading in the range of 5–60 mg NH4–N g TSS?1 day?1 does not have any significant effect on microfauna abundance. However, ammonia loading from 60 to 120 mg NH4–N g TSS?1 day?1 reduces microfauna abundance ca. 6-fold. Ciliate protozoa were the largest microfauna group during the whole period of study, representing ca. 75% of the total microfauna abundance. The largest group in the ciliate community was that of the free-swimming ciliates. This was followed by the group of attached and crawling ciliates. Specifically, the dominant ciliate species during the whole study period were Uronema nigricans, Vorticella microstoma-complex, Epistylis coronata, and Acineria uncinata. 相似文献
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Ultrasonographic anatomy of the atlanto‐occipital region and ultrasound‐guided cerebrospinal fluid collection in rabbits (Oryctolagus cuniculus) 
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下载免费PDF全文 Carlo Anselmi Sara Dias Jaume Martorell Marc Navarro Yvonne Espada Rosa Novellas 《Veterinary radiology & ultrasound》2018,59(2):188-197
Cerebrospinal fluid analyses are important for diagnosis of neurologic problems in rabbits and for translational research projects using rabbits as models. Blind puncture of the cisterna magna is the current standard technique for sampling cerebrospinal fluid in this species. However, the complexity and small size of the cisterna magna and surrounding structures are limitations of this technique. Aims of this prospective, anatomic, pilot study were to (1) describe the normal anatomy of the atlanto‐occipital region, (2) describe ultrasonographic anatomic landmarks, and (3) develop and evaluate a technique for ultrasound‐guided puncture of the cisterna magna for cerebrospinal fluid sampling in rabbits. Thirty healthy rabbits were included and the study was conducted in three stages. Three rabbit cadavers were used for the first stage of the study. Then, the second stage was completed using 13 rabbit cadavers. Finally, the third stage was completed in 14 live rabbits. The ultrasound‐guided puncture performed in 13 cadavers was successful at the first attempt in 10 cases, and at the second attempt in the remaining three cases. In the in vivo study, the ultrasound‐guided puncture was successful in all 14 cases, without signs of complications. Findings supported the use of ultrasound‐guided puncture of the cisterna magna as a safe technique that may be used routinely or when the sample of cerebrospinal fluid cannot be obtained with the blind technique in rabbits. 相似文献