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81.
82.
José L. Chávez Francis J. Pierce Todd V. Elliott Robert G. Evans Yunseop Kim William M. Iversen 《Precision Agriculture》2010,11(1):11-26
Precision irrigation systems can have inherent errors that affect the accuracy of variable water application rates controllers,
as well as affect the controllers’ performance when evaluated on different continuous move irrigation systems configurations.
The objective of this study was to assess the performance of a remote irrigation monitoring and control system (RIMCS) installed
on two separate linear move (LM) irrigation systems. The RIMCS varies water application rates by pulsing nozzles controlled
by solenoids connected via relays to a single board computer (SBC) with wireless Ethernet connection to a remote server. The
system also monitors irrigation system flow, pressure, position and wireless field sensor networks. The system was installed
on a LM irrigation system in Prosser, Washington, USA and on a LM in the Nesson Valley of North Dakota, USA. For the LM at
Prosser, four pre-defined irrigation patterns were imposed and variable rates were applied as a percentage of the nozzle base
application rate. Each nozzle was pulsed across the span length and along the LM travel direction. For the LM at the Nesson
Valley, a quadratic pattern was imposed pulsing banks of nozzles along the LM travel direction. Standard catch can tests were
performed and the system performance was evaluated by comparing measured catch can water depths with pre-determined target
values. The RIMCS accuracy was found to be in the range of the LM uniform water depth application uniformity coefficients
of 88–96%. The RIMCS was successfully transferred to another LM in North Dakota as indicated by the relatively low variable
rate application errors of –8.8 ± 8.1% and −0.14 ± 6.7% for the two spans. 相似文献
83.
Rajangam Udayakumar Sampath Kasthurirengan Ayyappan Vasudevan Thankaraj Salammal Mariashibu Jesudass Joseph Sahaya Rayan Chang Won Choi Andy Ganapathi Sei Chang Kim 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(2):91-98
The phenolic compounds and flavonoids were determined from the extracts of Withania somnifera root (WSREt) and leaf (WSLEt). The WSREt has 28.26 mg/g total phenolic compounds and 17.32 mg/g flavonoids, whereas WSLEt
has 5.4 mg/g total phenolic compounds and 5.1 mg/g flavonoids. The WSREt, WSLEt and glibenclamide were orally administered
daily to diabetic rats for 8 weeks. After the treatment, the levels of urine sugar, blood glucose, liver glycogen, and antioxidants
like vitamin C and E in plasma and superoxide dismutase (SOD), catalase (CAT), thiobarbituric acid reactive substances (TBARS),
glutathione peroxidase (GPx), glutathione-S-transferase (GST) and reduced glutathione (GSH) in liver, kidney and heart were
determined. Diabetic rats showed a significant (p < 0.05) elevation in glucose and TBARS and a significant (p < 0.05) reduction in glycogen, vitamin C and E, SOD, CAT, GPx, GST, and GSH levels when compared to normal control rats. Administration
of WSREt, WSLEt and glibenclamide to diabetic rats restored the levels to normal. In the light of aforesaid facts, it is suggested
that the presence of phenolic compounds including flavonoids in W. somnifera root and leaf extracts and their antioxidant activity may play a vital role in reduction of blood glucose level in alloxan-induced
diabetic rats. 相似文献
84.
Arshud Dar Anil Nichani Andy Potter Lorne A. Babiuk 《Research in veterinary science》2010,88(2):242-250
The analysis of CpG ODN induced innate immune responses in different animal species has shown substantial similarities and differences in levels and types of induced cytokines profile. The objectives of these studies were to identify innate immune biomarkers activated by three classes of CpG ODNs in pigs. For this purpose, we investigated the kinetics of innate immune responses in immune cells from pigs following in vitro and in vivo stimulation with CpG ODNs. The mRNA expression of cytokine and chemokine genes were assayed by SYBR@ green based quantitative real time PCR. A-class CpG ODN induced significant but transient levels of IFN-γ, IL-12 (P40), IL-6, IL-4 and TNF-α mRNA, C-class CpG ODN induced significant level of IFN-γ, IFN-α and IL-12 mRNA and the lowest level of IL-4 (Th-2 type) mRNA. A very low level of some cytokines stimulation was observed by GC ODNs. It is noteworthy, that IL-12 (P35) mRNA was significantly stimulated by B-class GpC ODN 7909. Interestingly, all classes of CpG ODNs induced significant level of IP-10 at 12 h post stimulation. These in vitro and in vivo observations suggest that interferon-γ inducible protein 10 (IP-10) may be a reliable biomarker for immune activity induced by CpG ODNs in pigs. 相似文献
85.
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87.
1. Many populations of sea‐ducks, which typically winter at sea but breed on fresh water, are declining. Numbers of common scoters Melanitta nigra (L.) breeding in Scotland halved between 1995 and 2007, despite most breeding sites having special conservation status. To identify potential conservation measures, a 3‐year study was conducted, investigating correlates of lake use by scoters. 2. At 26 scoter breeding lakes, food abundance (macroinvertebrates) and foraging habitats (substrates, water depth) were measured, and their associations with scoter lake use explored using multi‐model inference. Correlates of macroinvertebrate abundance (water quality, fish abundance) were also investigated. 3. Averaged over 3 years (2009–2011), these lakes held 26.7 (SE 6.3) females, around half the Scottish breeding population. Scoters occurred more often at lakes having abundant large‐bodied invertebrates and extensive shallow water. Lakes where the average weight of the largest invertebrate in each sample exceeded 4 mg had 9.2 times (females) or 27 times (broods) more scoter records than other lakes. Lakes where water depths (10 m from the shore) averaged less than 1.3 m had 2.5 times (females) or 12 times (broods) more scoter records than other lakes. 4. The abundance of large‐bodied invertebrates was greater where small fish species (mostly three‐spined sticklebacks Gasterosteus aculeatus) were more common and brown trout Salmo trutta were scarcer. 5. Results suggest two approaches to scoter conservation. At lakes used for hydro‐electricity generation, water level regimes that provide extensive shallow water should be tested to see if these benefit scoters. At lakes used for trout fishing, trout reduction by increased angling should be trialled, to see if this increases large‐invertebrate abundance and scoter use. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
88.
Steven J Cooke Zeb S Hogan Paul A Butcher Michael J W Stokesbury Rajeev Raghavan Austin J Gallagher Neil Hammerschlag Andy J Danylchuk 《Fish and Fisheries》2016,17(1):249-265
Recreational angling has been implicated in population declines of some marine and freshwater fish, but this activity is rarely considered as a threat or even halted when endangered species are targeted. Indeed, in some cases, anglers are drawn to fish for rare or endangered species. Conservation‐oriented behaviours such as catch‐and‐release are often practiced voluntarily due to the ethics of anglers, yet even in these cases, some fishing mortality occurs. Nonetheless, there are many indirect conservation benefits associated with recreational angling. Here, we present a series of case‐studies and consider whether catch‐and‐release angling for endangered fish is a conservation problem or a conservation action. If recreational angling activities contribute to population‐level consequences that are contrary to recovery strategies, then angling for endangered species would seem to be a poor option. However, as revealed by several case‐studies, there is much evidence that anglers are vocal and effective proponents of fish and habitat conservation, and for endangered species, they are often the only voice when other stakeholders are not engaged. Anglers may contribute directly to conservation actions via user fees (e.g. licences), philanthropic donations or by volunteering in research, education and restoration activities. However, it is important to quantify post‐release mortality as well as understand the full suite of factors influencing a given population or species to know the potential risks. A risk assessment approach outlined in the paper may be used by managers to determine when the benefits of angling for endangered species outweigh the risks. 相似文献
89.
Abstract A framework is developed to evaluate eradication as one of three alternative management responses to an outbreak of an invasive species: eradication, suppression or no action. This framework can be used to establish under what conditions an eradication option could provide an expected net economic benefit, and whether this net benefit exceeds that of the other two options. The eradication option is more likely to be preferred in situations where there is an immediate export benefit that is derived from eradication of the outbreak, and also the uncertainty associated with the likely success of eradication is low. 相似文献
90.
Xie C Yu K Zhong D Yuan T Ye F Jarrell JA Millar A Chen X 《Journal of agricultural and food chemistry》2011,59(20):11078-11087
Ultraperformance liquid chromatography coupled with hybrid quadrupole/ion mobility/orthogonal acceleration time-of-flight (oa-TOF) mass spectrometry (UPLC-IM-MS) was used to study the isomeric transformations of trans-5-caffeoylquinic acid, an extremely active compound present in multiple vegetables, fruits, and beverages. The UPLC/oa-TOF MS results proved that in phosphate buffer (pH 7.4), plasma, or urine sample, trans-5-caffeoylquinic acid first isomerizes to trans-4-caffeoylquinic acid and then to trans-3-caffeoylquinic acid by intramolecular acyl migration. When exposed to UV light, trans-3-, -4-, and -5-caffeoylquinic acids undergo cis/trans isomerization to form cis isomers. The isomerization was solely dependent on the pH of the matrix, as well as the incubation temperature, and was independent of metabolic enzymes. UPLC-IM-MS results revealed that a reversible cis/trans isomerization of caffeoylquinic acids could also be induced by the electric field in an electrospray source. Thus, understanding the possible role of electric field-induced isomerization of caffeoylquinic acids may help lessen the confusion between gas phase phenomena and liquid state chemistry when applying IM-MS analysis. The comprehensive understanding of caffeoylquinic acid isomerization transformations is crucial for the appropriate handling of samples and interpretation of experimental data. 相似文献