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Neville Millar G. Philip Robertson Peter R. Grace Ron J. Gehl John P. Hoben 《Mitigation and Adaptation Strategies for Global Change》2010,15(2):185-204
Nitrous oxide (N2O) is a major greenhouse gas (GHG) product of intensive agriculture. Fertilizer nitrogen (N) rate is the best single predictor
of N2O emissions in row-crop agriculture in the US Midwest. We use this relationship to propose a transparent, scientifically robust
protocol that can be utilized by developers of agricultural offset projects for generating fungible GHG emission reduction
credits for the emerging US carbon cap and trade market. By coupling predicted N2O flux with the recently developed maximum return to N (MRTN) approach for determining economically profitable N input rates
for optimized crop yield, we provide the basis for incentivizing N2O reductions without affecting yields. The protocol, if widely adopted, could reduce N2O from fertilized row-crop agriculture by more than 50%. Although other management and environmental factors can influence
N2O emissions, fertilizer N rate can be viewed as a single unambiguous proxy—a transparent, tangible, and readily manageable
commodity. Our protocol addresses baseline establishment, additionality, permanence, variability, and leakage, and provides
for producers and other stakeholders the economic and environmental incentives necessary for adoption of agricultural N2O reduction offset projects. 相似文献
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(E)-6,10-dimethyl-5,9-undecadien-2-ol (geranyl acetol), termed here fuscol, was identified as a male-produced pheromone emitted
by Tetropium fuscum (F.) and Tetropium cinnamopterum Kirby. In field experiments, traps baited with synthetic fuscol alone were not significantly attractive, but the combination
of fuscol plus host volatiles (a synthetic blend of monoterpenes plus ethanol) attracted significantly more male and female
T. fuscum and female T. cinnamopterum than did host volatiles alone. This is the first homoterpenoid alcohol to be described in the Cerambycidae, and the first
pheromone reported from the sub-family Spondylidinae. 相似文献
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Electron micrograph examination of the leaf and stem surfaces of Cleome viscosa L (Family Capparaceae) revealed the presence of secretory glandular trichomes with club-cylinder and cylinder morphologies. In the present study, the leaves and stems of C. viscosa were extracted with hexane and the extract was evaluated for the following biological activities: anti-bacterial, anti-fungal, contact insecticidal and nematicidal. The extract was found to be a potent anti-bacterial agent according to the thin layer chromatography autobiographic assay. Activity-directed isolation studies of the anti-bacterially active compounds led to a 14-member ring cembranoid diterpene being identified as one of the effective agents. Minimum inhibitory concentration (MIC) values (µg/spot) of 5.0 µg/spot and 1.0 µg/spot were found for the diterpene on Bacillus subtilis (Gram-positive) and Pseudomonas fluorescens (Gram-negative), respectively. The diterpene did not inhibit the growth of the fungus Cladosporium cucumerinum. The extract demonstrated a pyrethroid type of contact insecticidal activity on adult Cylas formicarius elegantulus Summer (Coleoptera: Curculionidae). The extract also had high nematicidal activity with a percentage Abbott's value of 72.69 on the plant parasitic nematode Meloidogyne incognita Chitwood; however, the extract lost its potency upon subfractionation. 相似文献
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《Agriculture, ecosystems & environment》1986,15(1):1-9
Lymantria dispar L. larvae exposed to the entomogenous nematodes Steinernema feltiae Filipjev and S. bibionis (Bovien) for ⩾ 16 h in laboratory petri dish tests averaged 93 and 91% mortality, respectively. Nylon pack cloth bands, lined with Pellon fleece or terry cloth, placed around oak tree boles were treated with nematode suspensions in central Pennsylvania. Fifth and 6th stage host larvae collected from beneath these bands after nematode treatment averaged 28% mortality. 相似文献
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An experimental group of homing pigeons (Columba livia f. domestica) learned to associate food with a magnetic anomaly produced by bar magnets that were fixed to the bowl in which they received
their daily food ration in their home loft; the control group lacked this experience. Both groups were trained to search for
two hidden food depots in a rectangular sand-filled arena without obvious visual cues; for the experimental birds, these depots
were also marked with three 1.15 × 106 μT bar magnets. During the tests, there were two food depots, one marked with the magnets, the other unmarked; their position
within the arena was changed from test to test. The experimental birds searched within 10 cm of the magnetically marked depot
in 49% of the test sessions, whereas the control birds searched there in only 11% of the sessions. Both groups searched near
the control depot in 11 and 13% of the sessions, respectively. The significant preference of the magnetically marked food
depot by the experimental birds shows that homing pigeons cannot only detect a magnetic anomaly but can also use it as a cue
for locating hidden food in an open arena. 相似文献
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A case of prenatally detected partial trisomy 15 and 16 is reported. Amniocentesis was performed at 14 weeks' gestation because a 6-mm nuchal translucency was detected on a dating ultrasound evaluation. Karyotype from amniocytes was suspect of an aberration concerning a marker chromosome. FISH analysis demonstrated that this marker chromosome was a der(15). A maternal chromosomal rearrangement t(15;16)(q13;p13.2) was confirmed. At birth, the proband was severely hydropic and had dysmorphic features, which included hypertelorism, micrognathia, incomplete separation of the maxilla and mandible, hyperflexed hands with overlapping fingers, hyposegmented right lung, and a single umbilical artery. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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F. Stöckmann 《Die Naturwissenschaften》1952,39(11):246-254
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Beike Leegte Birgit Sikkema-Raddatz Roel Hordijk Inge Davelaar Anneke van der Veen JanMaarten Cobben 《黑龙江环境通报》2001,21(7):550-552
We report a prenatal case of a maternally inherited abnormal chromosome 16, originally interpreted as a pericentric inversion only, but after family studies re-interpreted as a pericentric inversion (16) accompanied by an unbalanced (7;16) translocation. Because of the inversion 16 and an elder son with developmental delay and craniofacial dysmorphic features, in the past karyotyped as 46,XY, the chromosomes 16 of the mother and son were carefully re-examined. Using a whole chromosome 16 paint and sub-telomere probes of 16p and 16q, the karyotype of the mother was shown to be 46,XX,inv(16)(p11.2q23.2).ish t(7;16)(q36;p13.3)inv(16). Subsequently one chromosome 16 of the elder son appeared to be a der(16)t(7;16)(q36;p13.3). This is probably the result of a meiotic crossover between the chromosomes 16 in the mother. The prenatal karyotype was finally interpreted as 46,XY,inv(16)(p11.2q23.2).ish der(16)t(7;16)(q36;p13.3)inv(16). This is the same cytogenetic imbalance as his elder brother: a partial trisomy of chromosome 7 (q36→qter) and a partial monosomy of chromosome 16 (p13.3→pter). Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Treatment technologies for aqueous perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) 总被引:1,自引:0,他引:1
Chad D. Vecitis Hyunwoong Park Jie Cheng Brian T. Mader Michael R. Hoffmann 《Frontiers of Environmental Science & Engineering in China》2009,3(2):129-151
Fluorochemicals (FCs) are oxidatively recalcitrant, environmentally persistent, and resistant to most conventional treatment
technologies. FCs have unique physiochemical properties derived from fluorine which is the most electronegative element. Perfluorooctanesulfonate
(PFOS), and perfluorooctanoate (PFOA) have been detected globally in the hydrosphere, atmosphere and biosphere. Reducing treatment
technologies such as reverses osmosis, nano-filtration and activated carbon can remove FCs from water. However, incineration
of the concentrated waste is required for complete FC destruction. Recently, a number of alternative technologies for FC decomposition
have been reported. The FC degradation technologies span a wide range of chemical processes including direct photolysis, photocatalytic
oxidation, photochemical oxidation, photochemical reduction, thermally-induced reduction, and sonochemical pyrolysis. This
paper reviews these FC degradation technologies in terms of kinetics, mechanism, energetic cost, and applicability. The optimal
PFOS/PFOA treatment method is strongly dependent upon the FC concentration, background organic and metal concentration, and
available degradation time. 相似文献
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Anopheles gambiae s.l. is the main vector of malaria in Sub-Saharan Africa. Here, an estimated 1 million people die every year from this disease.
Despite considerable research on An. gambiae that increasingly explores sub-organismal phenomena, important facets of the field biology of this deadly insect are yet
being discovered. In the current study, we used simple observational tools to reveal that the habitat of larval An. gambiae is not limited within the boundaries of temporary mud puddles, as has been the accepted generalization. Thus, control tactics
aimed at immatures must consider zones larger than puddles per se. In fact, eggs are more likely to be found outside than
inside puddles. Eggs can develop and larvae can emerge on mud. Larvae are then capable of three distinct modes of terrestrial
displacement (two active and one passive), whereby, they can reach standing water. On mud bearing a film of water, larvae
actively displace backwards by sinusoidal undulations shown to be only a slight variation of the swimming motor program. On
drying mud, larvae switch to a slower and forward form of active locomotion resembling that of a crawling caterpillar. During
rains, small larvae may be passively displaced by flowing rainwater so as to be deposited into puddles. These capabilities
for being amphibious, along with very rapid growth and development, help explain how An. gambiae thrives in a highly uncertain and often hostile larval environment.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
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Soora Naresh Kumar Pramod Kumar Aggarwal Kumar Uttam Jain Surabhi D. N. Swaroopa Rani Nitin Chauhan Rani Saxena 《Mitigation and Adaptation Strategies for Global Change》2016,21(3):403-420
A simulation study has been carried out using the InfoCrop mustard model to assess the impact of climate change and adaptation gains and to delineate the vulnerable regions for mustard (Brassica juncea (L.) Czernj. Cosson) production in India. On an all India basis, climate change is projected to reduce mustard grain yield by ~2 % in 2020 (2010–2039), ~7.9 % in 2050 (2040–2069) and ~15 % in 2080 (2070–2099) climate scenarios of MIROC3.2.HI (a global climate model) and Providing Regional Climates for Impact Studies (PRECIS, a regional climate model) models, if no adaptation is followed. However, spatiotemporal variations exist for the magnitude of impacts. Yield is projected to reduce in regions with current mean seasonal temperature regimes above 25/10 °C during crop growth. Adapting to climate change through a combination of improved input efficiency, additional fertilizers and adjusting the sowing time of current varieties can increase yield by ~17 %. With improved varieties, yield can be enhanced by ~25 % in 2020 climate scenario. But, projected benefits may reduce thereafter. Development of short-duration varieties and improved crop husbandry becomes essential for sustaining mustard yield in future climates. As climatically suitable period for mustard cultivation may reduce in future, short-duration (<130 days) cultivars with 63 % pod filling period will become more adaptable. There is a need to look beyond the suggested adaptation strategy to minimize the yield reduction in net vulnerable regions. 相似文献