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Canine influenza virus is an emerging, highly contagious, respiratory pathogen that has not previously been radiographically described. In this retrospective case series study, we describe the thoracic radiographic appearance of confirmed canine influenza virus in six dogs. Radiographic findings varied, but included abnormal unstructured interstitial (one) and unstructured interstitial and alveolar (five) pulmonary patterns, which were distributed cranioventral (four), diffuse (one), and caudodorsal (one). The right middle (five), left cranial (five), and right cranial (four) lung lobes were most commonly affected. Additionally, mild pleural effusion was present in one dog. Intrathoracic lymphadenopathy and cranial mediastinal widening/fluid accumulation were not detected in any dog. Canine influenza virus should be considered as a differential diagnosis for canine patients with respiratory signs and a cranioventral unstructured interstitial to alveolar pulmonary pattern.  相似文献   
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A serious outbreak of barley yellow dwarf luteovirus (BYDV, MAV-type) on wheat in the Garhwal Hills, Central Himalayas, India is reported. This is the first conclusive evidence based on serology for the presence of MAV-BYDV in India.  相似文献   
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Fabula  J. V.  Sharda  Ajay  Mishler  B. 《Precision Agriculture》2022,23(5):1675-1687

Agricultural sprayers are utilized in applying pesticides to control pests and diseases in crops. The increase in machine size and a better control system have been associated with increased productivity, improved efficiency and minimized the impact of the chemical on the environment. However, wider booms may contribute to application error due to the difference in speed between the inner and outer boom section when applying in curvilinear passes. Field tests were conducted in three irregular shaped fields with varying terrain using a 36.6-m self-propelled sprayer with a turn compensation technology. The results showed that turning occurred near the grassed waterways, boundaries and end of headlands. The product was applied during turning to 19.0% of Field 1, 17.8% of Field 2 and 22.5% of Field 3. These could have been the percentage of field areas that may receive more or less product if the sprayer was not equipped with turn compensation technology. As expected, the speed difference between the inner and outer boom increases as the radius of turn decreases. The speed difference could translate to an under-application on the outer boom section where the speed is much faster and over-application on the inner boom section where the speed is slower. The application errors from such speed differential could vary from ??48.2 to +?1058.0%, depending on the turning radius. However, the pulse width modulation system implemented duty cycles based on turning speeds, which resulted to a 90.0% application rate uniformity across the field regardless of the travel path during operation.

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Four feeding experiments, replacing 25% (T1), 50% (T2), 75% (T3) and 100% (T4), by dry weight, of the live feed Artemia nauplii for Cyclop‐eeze, a new larval feed that was claimed to contain the highest known levels of astaxanthin and omega‐3 polyunsaturated fatty acids, were compared against a control that was fed with Artemia and egg custard alone, to the larvae of giant freshwater prawn Macrobrachium rosenbergii (De Man 1879). Analysis of different production characteristics of the larvae revealed that the highest survival up to postlarvae (PL) stage was obtained for T2 in which 50% of the Artemia nauplii were replaced by Cyclop‐eeze [freeze‐dried (FD) deep frozen (DF)], and the highest astaxanthin content of the larval tissue obtained in T4 in which the larvae were fed 100% Cyclop‐eeze, although the survival rate was the lowest in this treatment. The costs of different treatments were also compared. The Artemia consumption million−1 larvae was the highest in control (11490 g), followed by T1 (8240 g), T2 (4990 g), T3 (3730 g) and T4, which completely replaced Artemia from stage 5 onwards (1830 g). The highest consumption of Cyclop‐eeze million−1 larvae was in T4 (1670 and 10 880 g), followed by T3 (850 and 5560 g), T2 (410 and 2690 g) and T1 (230 and 1490 g) of FD and DF, respectively. The astaxanthin contents of the late‐stage larvae fed under the four treatments were 24.90, 27.40, 28.60 and 35.60 μg g−1 tissue for T1, T2, T3 and T4, respectively, while that of the control was 23.70 μg g−1. The lowest cost of live feeds million−1 PL was obtained for T2 (US$ 428.60), followed by T1 (US$ 490.46), control (US$ 529.07) and T3 (US$ 583.26), while it was the highest for T4 (US$ 890.93). The results indicated that Cyclop‐eeze could economically replace Artemia nauplii at 50% level that could significantly improve the survival and carotenoid composition of the larvae of M. rosenbergii.  相似文献   
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In recent years, conventional rice production technologies have been leading to deterioration of soil health and declining farm profitability due to high inputs of water and labor. Conservation agriculture(CA) based resource-conserving technologies i.e. zero-tillage(ZT), raised-bed planting and direct-seeded rice(DSR) have shown promise as alternatives to conventional production technologies to overcome these problems. Present study was undertaken during 2009–2012 to establish an understanding of how permanent raised bed cropping system could be practiced to save water at the field application level to improve water productivity and also have the capability to enhance productivity, profitability and soil physical quality. The results showed that among different crop establishment techniques, conventional-tilled puddle transplanted rice(CT-TPR) required 14%-25% more water than other techniques. Compared with the CT-TPR system, zero till direct-seeded rice(ZT-DSR) consumed 6%–10% less water with almost equal system productivity and demonstrated higher water productivity. Wide raised beds saved about 15%–24% water and grain yield decrease of about 8%. Direct-seeded rice after ZT or reduced tillage or on unpuddled soil provided more net income than CT-TPR. The CTTPR system had higher bulk density and penetration resistance due to compaction caused by the repeated wet tillage in rice. The steady-state infiltration rate and soil aggregation( 0.25 mm) were higher under permanent beds and ZT and lower in the CT-TPR system. Under CT-TPR, soil aggregation was static across seasons, whereas it improved under no-till and permanent beds. Similarly, mean weight diameter of aggregates was higher under ZT and permanent beds and increased over time. The study reveals that to sustain the rice productivity, CA-based planting techniques can be more viable options. However, the long-term effects of these alternative technologies need to be studied under varying agro-ecologies in western Uttar Pradesh, India.  相似文献   
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Low availability of phosphorus(P) is a major constraint for optimal crop production, as P is mostly present in its insoluble form in soil. Therefore,phosphate-solubilizing bacteria(PSB) from paddy field soils of the Indo-Gangetic Plain, India were isolated, and their abundance was attempted to be correlated with the physicochemical characteristics of the soils. Ninety-four PSB were isolated on Pikovskaya's agar medium, and quantitative phosphate solubilization was evaluated using NBRIP medium. The isolates solubilized P up to a concentration of 1 006 μg mL~(-1) from tricalcium phosphate with the secretion of organic acids. These isolates were identified by 16 S rRNA gene sequence comparison, and they belonged to Gammaproteobacteria(56 isolates),Firmicutes(28 isolates), Actinobacteria(8 isolates), and Alphaproteobacteria(2 isolates). Phylogenetic analysis confirmed the identification by clustering the isolates in the clade of the respective reference organisms. The correlation analysis between PSB abundance and physicochemical characteristics revealed that the PSB population increased with increasing levels of soil organic carbon, insoluble P, K~+, and Mg~(2+). The promising PSB explored in this study can be further evaluated for their biofertilizer potential in the field and for their use as potent bio-inoculants.  相似文献   
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The bacterium Deinococcus radiodurans survives ionizing irradiation and other DNA-damaging assaults at doses that are lethal to all other organisms. How D. radiodurans accurately reconstructs its genome from hundreds of radiation-generated fragments in the absence of an intact template is unknown. Here we show that the D. radiodurans genome assumes an unusual toroidal morphology that may contribute to its radioresistance. We propose that, because of restricted diffusion within the tightly packed and laterally ordered DNA toroids, radiation-generated free DNA ends are held together, which may facilitate template-independent yet error-free joining of DNA breaks.  相似文献   
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