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941.
Global climate warming has been exerting impacts on agricultural pests. Pests also take some strategies to adapt to climate change. Understanding such adaptation could benefit more accurate predictions and integrated management of pest. However, adaptation to climate change has not been widely investigated in agricultural pests but has been well documented in model species, Drosophila, and reviewed by Hoffmann before 2003. To provide recent progress and references for agricultural entomologists who interested in thermal biology, here we have reviewed literatures since 2003 about adaptation to temperature changes under climate change. We mainly summarized thermal adaptation of Drosophila (especially to high temperatures) from three aspects, behaviors, plastic responses and micro-evolution and discussed how Drosophila increases their heat tolerance through these three mechanisms. Finally, we summarized the measures of thermotolerance and concluded the main progress in recent decade about the behavioral thermoregulation, mortality risks driven by limited evolutionary and plastic response under climate change, geographic distribution based on basal rather than plastic thermotolerance. We propose future work focus on better understanding adaptation of organisms including agricultural pests to climate change.  相似文献   
942.
Background: The present study aimed to fabricate surface-modified chitosan nanoparticles with two mucoadhesive polymers (sodium alginate and polyethylene glycol) to optimize their protein encapsulation efficiency, improve their mucoadhesion properties, and increase their stability in biological fluids. Method: Ionotropic gelation was employed to formulate chitosan nanoparticles and surface modification was performed at five different concentrations (0.05, 0.1, 0.2, 0.3, 0.4% w/v) of sodium alginate (ALG) and polyethylene glycol (PEG), with ovalbumin (OVA) used as a model protein antigen. The functional characteristics were examined by dynamic light scattering (DLS), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM)/scanning transmission electron microscopy (STEM). Stability was examined in the presence of simulated gastric and intestinal fluids, while mucoadhesive properties were evaluated by in vitro mucin binding and ex vivo adhesion on pig oral mucosa tissue. The impact of the formulation and dissolution process on the OVA structure was investigated by sodium dodecyl-polyacrylamide gel electrophoresis (SDS-PAGE) and circular dichroism (CD). Results: The nanoparticles showed a uniform spherical morphology with a maximum protein encapsulation efficiency of 81%, size after OVA loading of between 200 and 400 nm and zeta potential from 10 to 29 mV. An in vitro drug release study suggested successful nanoparticle surface modification by ALG and PEG, showing gastric fluid stability (4 h) and a 96 h sustained OVA release in intestinal fluid, with the nanoparticles maintaining their conformational stability (SDS-PAGE and CD analyses) after release in the intestinal fluid. An in vitro mucin binding study indicated a significant increase in mucin binding from 41 to 63% in ALG-modified nanoparticles and a 27–49% increase in PEG-modified nanoparticles. The ex vivo mucoadhesion showed that the powdered particles adhered to the pig oral mucosa. Conclusion: The ALG and PEG surface modification of chitosan nanoparticles improved the particle stability in both simulated gastric and intestinal fluids and improved the mucoadhesive properties, therefore constituting a potential nanocarrier platform for mucosal protein vaccine delivery.  相似文献   
943.
This study aimed to investigate the effects of key lime juice (KL) in combination with vacuum packaging (VP) or air storage (SB) on the quality changes of white shrimp stored at 2 ± 1ºC. The quality was assessed using microbiological analysis, color measurement, pH, and total volatile base nitrogen (TVBN). Treatment with KL exhibited inhibitory activity on the growth of spoilage microflora. KL in combination with VP revealed a lower bacterial count in the range of 4.37–4.91 log CFU gˉ1 on day 12 of storage as compared to other treatments. VP + KL and VP samples could inhibit melanosis. In addition, lower TVBN content was obtained in VP + KL (5.33 mg N/100 g), followed by VP (6.03 mg N/100 g) samples on day 12 of storage (p < 0.05). VP in combination with KL had the lowest loss of quality changes for the white shrimp. Therefore, VP + KL could be used as an alternative preservative method to extend the shelf life for white shrimp.  相似文献   
944.

The effects of anthropogenic noise have garnered significant attention in marine ecosystems, but comparatively less is known about its impacts on freshwater ecosystems. For fish that provide parental care, the effects of acoustic disturbance could have fitness-level consequences if nest tending behavior is altered. This study explored the effects of motorboat noise on the parental behavior of nesting male smallmouth bass (Micropterus dolomieu; Lacépède, 1802), an important freshwater game fish in North America that provides sole paternal care to offspring. Specifically, we evaluated how boat noise proximity to a bass nest (ranging from 4.5 to 90 m) influenced paternal care behaviors. A total of 73 fish were exposed to a 3-min motorboat playback designed to simulate a boat sound that typically occurs in areas near littoral nesting sites. The fish were video recorded, and their behaviors were analyzed before, during, and after exposure to the playback. Residency time was the only behavioral metric to be adversely affected by noise playbacks but only when in close proximity to the speaker. Our results suggest that boat noise may have an impact on bass reproductive fitness in specific contexts where combustion motors are used near shore during the nesting period. The largely null findings may indicate a resilience to boat noise and/or habituation to the noise. In addition, boats displace water and create waves that represent another form of disturbance that could be experienced by fish but was not simulated here. Future research should integrate behavioral and physiological responses to boat noise and other aspects of boat disturbance to better understand the fitness impacts of boating activity on freshwater fish.

  相似文献   
945.
Qaswar  Muhammad  Chai  Rushan  Ahmed  Waqas  Jing  Huang  Han  Tianfu  Liu  Kailou  Ye  Xinxin  Xu  Yongmei  Anthonio  Christian Kofi  Zhang  Huimin 《Journal of Soils and Sediments》2020,20(3):1285-1296
Journal of Soils and Sediments - The aim of this study was to investigate the effect of combined use of chemical fertilizers with wheat straw and swine manure on rice yield and&nbsp;phosphorus...  相似文献   
946.
Qaswar  Muhammad  Yiren  Liu  Jing  Huang  Kaillou  Liu  Mudasir  Muhammad  Zhenzhen  Lv  Hongqian  Hou  Xianjin  Lan  Jianhua  Ji  Ahmed  Waqas  Dongchu  Li  Huimin  Zhang 《Journal of Soils and Sediments》2020,20(4):2093-2106
Journal of Soils and Sediments - Fertilization is a vital approach to increase the crop yield by enhancing soil fertility, but some of the fertilizer sources such as pig manure contain...  相似文献   
947.
Scanner technology is emerging as a cost‐effective and robust imaging alternative to camera‐based systems in many applications. However, scanner technology is changing so fast that image quality can vary from model to model. It is critical that images scanned with different scanners be brought to a common basis for processing and measurement through a calibration process that eliminates scanner‐to‐scanner variability. The focus of this research was to investigate scanner‐to‐scanner variability and develop color correction or mapping functions to allow for machineindependent grain inspection. Various makes and models of scanners were compared for optical and color characteristics. Three different color correction methods wereevaluated: grayscale (GS) transformation, redgreen‐blue (RGB) transformation, and histogram matching. All three models of color correction worked within satisfactory tolerance for a multicolor Q60 chart. However, for grain samples of a limited color range, the histogram matching approach performed better than GS and RGB transformations for scanner calibration. The color‐corrected test images matched the reference images within 3 grey values. Differences between the three models of color correction are discussed.  相似文献   
948.
A 150‐days study was conducted on the continuous exposure of magnetized water at 0.00, 0.10, 0.15 and 0.20 Tesla (T) on quadruplicate treatments of Jade Perch Scortum barcoo juveniles in a recirculating system. Each replicate consisted of 18 fish with an average weight of 7.52 g over all treatments. The feeding efficiencies, growth, whole‐body proximate plasma parameters, survival were measured and liver histopathology was observed. Our results show no significant improvement in water quality parameters, specific growth rate and body weight gain in this study. However, the best feed conversion ratio was recorded in fish exposed to 0.10, 0.15 and 0.20 T, which are significantly better than the control 0.00 T. Though survival was unaffected but plasma biochemistry and liver histopathology were affected even within the treatment. No liver, plasma or blood abnormalities were detected in fish exposed to 0.10 T and the control 0.00 T. But, one out of four livers from fish in the 0.15 T treatment showed a localized inflammatory response. These changes increased in the liver of fish exposed to 0.20 T, high AST and necrosis in this group is evidence of the liver cells damaged or been at risk. A significantly higher crude protein and lipid were noticed in the exposed fish compared with the control, 0.15 T had the highest crude protein and lipid while the control has the lowest. Based on the overall findings, on growth performance and looking at other factors like absence of any physiological disorder 0.10 T can be used as an effective and affordable technique improve the feeding efficiencies of Jade Perch.  相似文献   
949.
This study was conducted to characterize the causative agent of streptococcosis in tilapia (Oreochromis niloticus) and control of Streptococcus infection by means of garlic (Allium sativum) supplementation. The morphological, biochemical and polymerase chain reaction amplification confirmed 11 isolates belong to Streptococcus iniae from the infected fish eyes and tissue samples. Random screening of 12 well‐known medicinal plant parts against S. iniae revealed the garlic extract as the most effective herbal recovery against Streptococcus infection. In vivo challenge test with dietary supplementation of garlic powder significantly improved survival rates of fish against S. iniae infections, and modulate the microbial community and cytokine gene expression profiling in the intestine of the experimental tilapia. Among the two garlic supplemented treatments, 1.0 g garlic supplemented diet significantly increased (p < 0.05) the survival rates of tilapia and the gut bacterial operational transitional units abundance for Proteobacteria and Tenericutes, the phyla associated with healthy intestinal flora. The bacterial diversity index also found high with garlic supplemented diets. Significant upregulations of IL‐10 and IL‐17F gene expression in the intestinal tissue were observed with 1.0 g garlic supplemented diet where IL‐8 and IL‐1β expression levels were relatively static. The dietary supplementation of garlic, therefore, could be effective in the prevention of S. iniae infection in fish.  相似文献   
950.
为了明确总酚、总黄酮及植酸在柚果果皮和果肉中的分布与积累特征,以平和县15个柚品种为供试材料,分别于果实膨大期和成熟期取样,对果实不同部位(果皮和果肉)总酚、总黄酮及植酸相对含量和积累量进行分析.结果表明:蜜柚果实富含总酚和总黄酮,而植酸含量相对较低;总酚、总黄酮及植酸相对含量和积累量在果皮和果肉上存在显著的品种差异;...  相似文献   
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