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Wild oat (Avena fatua L.) is one of the most problematic weed species in western Canada due to widespread populations, herbicide resistance, and seed dormancy. In wheat (Triticum aestivum L.), and especially in shorter crops such as lentil (Lens culinaris Medik.), A. fatua seed panicles elongate above the crop canopy, which can facilitate physical cutting of the panicles (clipping) to reduce viable seed return to the seedbank. However, the viability of A. fatua seed at the time of panicle elongation is not known. The objective of this study was to determine the viability of A. fatua seed at successive time intervals after elongation above a wheat or lentil crop canopy. A 2-yr panicle clipping and removal study in wheat and lentil was conducted in Lacombe, AB, and Saskatoon, SK, in 2015 and 2016 to determine the onset of viability in A. fatua seeds at successive clipping intervals. Manual panicle clipping of A. fatua panicles above each crop canopy began when the majority of panicles were visible above respective crop canopies and continued weekly until seed shed began. At the initiation of panicle clipping, A. fatua seed viability was between 0% and 10%. By the last clipping treatment (approximately 6 to 7 wk after elongation), 95% of the A. fatua seeds were viable. Seed moisture and awn angle were not good predictors of A. fatua viability, and therefore were unlikely to provide effective tools to estimate appropriate timing for implementation of A. fatua clipping as a management technique. Based on A. fatua seed viability, earlier clipping of A. fatua is likely to be more effective in terms of population management and easier to implement in shorter crops such as lentil. Investigations into long-term effects of clipping on A. fatua populations are needed to evaluate the efficacy of this management strategy on A. fatua.
Safeners have been widely used to reduce phytotoxicity to crops, thus serving as an alternative weed control strategy. Benoxacor and fenclorim safeners have the potential to protect plants from herbicide phytotoxicity by increasing glutathione S-transferase (GST) activity within the plant. The study aimed to evaluate the safening effect of benoxacor and fenclorim on tomato against selected herbicides applied postemergence. The experiment was conducted in a greenhouse in a completely randomized designed with four replications, in a 9 x 3 factorial scheme, where Factor A consisted of eight herbicides including a nontreated control, and Factor B consisted of two safeners including a nontreated control. The herbicide treatments were sulfentrazone (0.220 kg ai ha-1), fomesafen (0.280 kg ai ha-1), flumioxazin (0.070 kg ai ha-1), linuron (1.200 kg ai ha-1), metribuzin (0.840 kg ai ha-1), pyroxasulfone (0.220 kg ai ha-1), and bicyclopyrone (0.040 kg ai ha-1). Safener treatments consisted of benoxacor (0.67 g L-1) and fenclorim (10 µM). Tomato seeds were immersed in safener solution before sowing and herbicides were applied when tomato plants were at the 3-leaf stage, or 25 days after sowing. Visible injury was scored at 3, 7, 14, and 21 days after application (DAA), and shoot biomass was recorded 21 DAA. Seed treatment with fenclorim reduced injury caused by imazamox and bicyclopyrone, by 5.5 and 1.3 times, respectively, while benoxacor reduced the injury from bicyclopyrone 1.3 times. In addition, tomato plants pre-treated with fenclorim showed a lesser reduction in biomass after application of imazamox, fomesafen, and metribuzin, while benoxacor pre-treated plants showed lesser biomass reduction after metribuzin application. Thus, the use of safeners promotes greater crop selectivity, allowing the application of herbicides with different mechanisms of action on the crop.
In 2005, Cabo Verde became the second African country to receive the new foreign aid programme of the USA, the Millennium Challenge Account (MCA). It was among the few recipients of a second grant. Foreign aid has always been a controversial and hotly contested issue, and the MCA is no exception. This paper, based partly on personal experience with the programme, provides a critical examination of the nature, process and implementation of the MCA grants in Cabo Verde. The country had campaigned aggressively for the grants. The MCA not only financed important public investments, it was debt-free and without conditionalities. However, even while it allowed more leeway over its use and implementation compared with other aid programmes, it engendered its own challenges.
Harmen van der Wilt explains the ICC’s and the Rome Statute’s ‘design selectivity’, i.e., the ICC’s legal, structural and political limitations and well as its inherent selectivity when selecting ‘situations’ and ‘cases’. He analyzes how the problem of selectivity in international criminal law, i.e., the systematical exemption of entire categories of perpetrators from accountability, creates tensions with traditional theories of punishment. In emphasizing the shift from punishment to trial, he argues that international criminal law’s inherent selectivity can best be processed by expressivism. However, contemporary international criminal law, he concludes, conveys the ‘perverse message’ that ‘criminal responsibility depends on the party or nation one belongs to and the side on which one fights’. For the future, he calls for an approach of ‘dauntless perseverance’.
The elimination of unwanted catch in mixed species fisheries is technically challenging given the complexity of fish behaviour within nets. Most approaches to date have employed technologies that modify the nets themselves or use physical sorting grids within the gear. There is currently increasing interest in the use of artificial light to either deter fish from entering the net, or to enhance their escapement from within the net. Here, we evaluated the differences in catch retained in a standard otter trawl, relative to the same gear fitted with a square mesh panel, or a square mesh panel fitted with LEDs. We found that the selectivity of the gear differed depending on water depth. When using a square mesh panel in shallow depths of 29–40 m the unwanted bycatch of whiting and haddock was reduced by 86% and 58% respectively. In deep, darker water (45–95 m), no change in catch was observed in the square-mesh panel treatment, however when LEDs were added to the square-mesh panel, haddock and flatfish catches were reduced by 47% and 25% respectively. These findings demonstrate the potential to improve the performance of bycatch reduction devices through the addition of light devices to enhance selectivity. The results also highlight species-specific and site-specific differences in the performance of bycatch reduction devices, and hence a more adaptive approach to reduce bycatch is probably required to maximize performance.
Iranian coastal fishers targeting narrow-barred Spanish mackerel (Scomberomorus commerson) recently replaced their historical multifilament gillnets with those made from monofilament, evoking management concerns over potential increases in catch-per-unit-of-effort. During 20 fishing days, we compared catches from replicate surface-set gillnets that were identical in terms of mesh size (140 mm stretched opening), length (180 m), depth (30 m), hanging ratio (0.56) and spatio-temporal deployment, but had different materials: multifilament (1.8-mm diameter twisted twine) vs monofilament (0.8-mm diameter twine). Compared with the multifilament gillnet, there was a trend of greater catches (up to 1.3×) of S. commerson and another retained species, mackerel tuna (Euthnus affinis), along with one discarded species, giant catfish (Netuma thalassina) by the monofilament gillnet. However, statistical significance was restricted to E. affinis catches and a bias towards smaller S. commerson. These differences were attributed to species-specific catching mechanisms within gillnet material, with larger S. commerson retained by their teeth in the multifilament and all E. affinis more securely retained by their deeper bodies in the monofilament. Gillnet materials require regulation to preclude excessive effort on fully exploited stocks of species such as S. commerson.
Over the last decade, there has been an increased focus on describing condensed carbonaceous matter in rocks in several ultramafic settings and in experiments. This organic carbon – unaccounted for until now – seems to be ubiquitous in the crust, with profound implications for the deep carbon cycle and the sustainability of deep microbial ecosystems. Among the suite of abiotic organic compounds that may have formed abiotically in serpentinizing systems in particular are molecules of prebiotic interest, including a series of amino acids. In this chapter, the geochemical pathways for the abiotic synthesis of condensed carbonaceous matter are described, as well as the thermodynamic stability of such compounds and both their biotic and abiotic processing in the crust.
In the same spirit as the previous chapter, the present one endeavors to further contextualize the larger puzzle in which L3 morphosyntactic studies are located. In fact, it is important to understand the historical provenance of the theories and related empirical work within L3/Ln morphosyntax on which the remainder of the book will focus. In equal measure, it is important to keep abreast of the trends in the related fields of multilingual acquisition and processing, not only to be a well-rounded L3/Ln scholar but also to understand one’s own subarea better and to ensure the continuity of ideas via potential, when appropriate, cross-fertilization. Thus, before traveling down the road of L3/Ln morphosyntax and transfer studies from a formal linguistic perspective, it makes sense to recap what has been or is being done in the related fields of multilingual lexical processing and acquisition, as well as in phonology.
This study aimed to evaluate the effects of toxic baits and attractants for fruit flies on the biology of its parasitoid Fopius arisanus. We tested two food-based attractants; hydrolysed corn protein (Biofruit® 3%) and sugarcane molasses (7%), their mixtures with spinosad and malathion-based insecticides, and a ready-to-use commercial bait (Success 0.02 CB®). Malathion-based lures were used as references for mortality (i.e., positive control), while negative control was honey. The formulations Biofruit® + malathion (T1), molasses + malathion (T2), and spinosad + molasses (T3) were toxic to F. arisanus, being classified as harmful (class 4). In addition, toxic baits composed of Biofruit + spinosad (T4) reduced parasitism by 97.99%, being rated as moderately harmful (class 3). Yet, Success 0.02 CB® (T7) was considered slightly toxic (class 2), causing a 64.55% reduction in parasitism. Regarding the biological parameters of F. arisanus, offspring number and parasitoid longevity were significantly reduced by using hydrolysed protein attractants when compared to the control (honey). However, sugarcane molasses improved parasitoid reproduction and longevity, as did the honey. Lastly, ingestion tests showed the major role of attractants in toxic-bait formulations against F. arisanus.
Phonological selectivity is a phenomenon where children preselect which target words they attempt to produce. The present study examines selectivity in the acquisition of complex onsets and codas in English, and specifically in the acquisition of biconsonantal (CC) clusters in each position compared to triconsonantal (CCC) clusters. The data come from the naturalistic productions of three English-speaking children. The results indicate that children only attempt to produce target tokens with a CCC onset after they have successfully produced target tokens with a CC onset, and that the same occurs in the case of codas. Frequency, morphological complexity, sonority, and /s/ clusters were examined and ruled out as possible explanations of these acquisition patterns. Overall, this suggests that children are selective in their target words, and only attempt to produce words that contain a cluster after they have produced words containing a shorter cluster of the same type (i.e., onset/coda).
In this study, a new ultra-wideband (UWB) band-edge selectivity antenna with a modified radiation slot using defected ground structure (DGS) is presented to obtain bandpass filtering reflection coefficient and gain performance. The well-designed DGS is designed on backside metallic of the substrate and can be seen as a low-pass filter that provides a good roll-off at a higher frequency. By connecting the DGS and the stepped slot and making them merge with each other, good cut-off property in the upper passband and better in-band impedance characteristics are obtained. Measured results show that the proposed design not only shows good band-edge selectivity in reflection coefficient and gain performance but also has a good impedance matching of −13.5 dB reflection coefficients and a good radiation efficiency of 90% in the operating frequencies. The measured bandwidth defined with the reflection coefficient less than −10 dB is from 3.1–11.2 GHz. Furthermore, the size of the filtering UWB antenna is 22 mm × 12 mm, which is smaller than many individual UWB antennas and UWB filters.
Traditionally, EU state aid law has been attached to the goals of maintaining free competition and preventing the distortionary effects of Member States’ economic intervention, while social considerations have been considered immaterial to state aid control. However, in more recent years, EU state aid law has acquired a clearer ‘social dimension’, indirectly streamlining national subsidies towards social goals. The entry into force of the Treaty of Lisbon, and particularly of Articles 3(3) TEU and 9 TFEU, has had an impact on the way in which social goals have been taken into account in the application of the state aid provisions. In the last decade, the European Commission has sought out a more appropriate balance between the main objective of preserving competition in the internal market on the one hand, and social objectives, also enshrined nowadays in the Treaties, on the other. This ‘social dimension’ is still underdeveloped, but emerges to varying degrees when looking respectively at the definition of state aid under Article 107(1) TFEU, at the scope of the derogations under Articles 107(2) and 107(3) TFEU and at the secondary legislation adopted for their implementation.
The conceptualisation of Alzheimer's disease as an illness with ‘no future’ exposes people with the condition to significant fear and stress. Therefore, exploring how people look ahead to the future in the face of Alzheimer's disease is of foremost importance. Semi-structured interviews (N = 14) explored the future outlook of people with early (N = 5) and late-onset (N = 7) Alzheimer's disease and those who support them (N = 14). Thematic analysis identified how participants managed their changing futures through focusing on positive information, and taking ‘one day at a time’. Younger and older people shared similar future outlook and subsequent coping strategies, as predicted by Carstensen's Socioemotional Selectivity Theory. Both people with Alzheimer's disease and those who support them avoided looking far ahead as a way of managing the uncertain future, and had little awareness of future planning in the context of current policies. Such avoidance suggests that policy which encourages future planning should consider its utility and explore ways of helping people to plan, whilst focusing on daily living.
A compact high-isolation power divider with bandpass response and high-frequency selectivity is presented in this letter. Two dual-mode resonators are used to realize filtering response. The circuit size of the proposed power divider can be reduced by using dual-mode capacitance loaded square meander loop resonators. Due to capacitive load, the resonator can exhibit slow-wave characteristics, which can be utilized to suppress harmonics and reduce size. The simulated and measured results show reasonable agreement.
FM-to-AM conversion for angular filtering based on transmitted volume Bragg gratings (TBGs) is discussed. Simulation results show that a narrower spectral selectivity of TBGs led to stronger FM-to-AM conversion. Good angular selectivity and a wide bandwidth for the TBGs can be obtained by controlling the grating period and thickness. FM-to-AM conversion can be effectively suppressed and the distortion criterion for the filtered beam reduces to less than 5%. FM-to-AM conversion of TBGs is demonstrated in the ‘Shenguang’ facility, and the results are in good agreement with the simulation.
The ultra-wideband bandpass-response power divider with high-frequency selectivity is presented in this paper. This power divider consists of an impedance transformer, a filter network, and two isolation resistors. In order to realize the ultra-wideband filtering performance, parallel coupling lines and parallel open-circuit branches are applied to the second impedance converter. A resistor is added to the ends of the coupling lines to achieve good isolation and output return loss. The equivalent-circuit method is employed to analyze the presented power divider. The power divider, working at 3.45–8.29 GHz, is designed and fabricated. Two transmission zeros are generated at 2.8 and 9 GHz, respectively, and the out-of-band suppression is >13 dB. The measured results are in good agreement with the simulation ones.
Tall fescue is susceptible to injury from many acetolactate synthase (ALS) inhibitors used for broadleaf weed control in turfgrass. Florasulam is an ALS inhibitor that selectively controls broadleaf weeds in tall fescue, but the mechanisms for selectivity are not well understood. The objective of this research was to evaluate the physiological basis of tall fescue tolerance to florasulam. In greenhouse experiments, florasulam rates required to injure tall fescue 20% (I20) and white clover 80% (I80) measured 320 and 65 g ai ha–1, respectively. The I20 and I80 values of another ALS inhibitor, flucarbazone, on these species measured 33 and 275 g ai ha–1, respectively. In laboratory experiments, the time required to reach 50% foliar uptake for 14C-florasulam and 14C-flucarbazone measured 23 and 62 h for white clover, respectively, and >72 h for both herbicides in tall fescue. The half-lives of florasulam and flucarbazone in tall fescue were 15 and 40 h, respectively, whereas the half-life in white clover was >72 h for both herbicides. The concentrations of florasulam and flucarbazone required to inhibit ALS enzymes 50% in excised leaves of tall fescue measured >1,000 and 32 μM, respectively. The selectivity of florasulam for white clover control in tall fescue is associated with differential levels of absorption and metabolism between species. Tall fescue has faster metabolism and less ALS enzyme inhibition from florasulam as compared to a more injurious ALS inhibitor, flucarbazone, which contributes to the differential tolerance levels between these herbicides.
Natural enemies are exposed to insecticide sprays for herbivorous species and may evolve field resistance to insecticides. Natural enemies selected for resistance in the field, however, are welcome for pest control. The susceptibility of 20 populations of Eriopis connexa from various crop ecosystems to λ-cyhalothrin was tested. Three bioassays were conducted: (i) topical treatment with lethal dose (LD)50 previously determined for populations considered standard for susceptibility (LD50S) and for resistance (LD50R) to λ-cyhalothrin at technical grade; (ii) dose–mortality assay to calculate the LD for populations exhibiting significant survival to the LD50R; and (iii) determination of survival when exposed to dried residues at field rates. Among the 20 tested populations, seven populations did not survive or survival rates were lower than 10% when treated with LD50R; three populations survived >20%, but lower than 50%; while ten populations exhibited equal or greater survival rates compared with the 50% expected survival for the LD50R. Thus, these ten populations were subjected to dose–mortality response, and the LD50 values varied from 0.046 to 5.44 µg a.i./insect with resistance ratio of 8.52- to 884.08-folds. Adults from these ten populations that were ranked as resistant according to the LD50R exhibited survival from 44.5 to 100% exposed to the lowest and from 38.8 to 100% exposed to the highest field rates of λ-cyhalothrin, respectively. Otherwise, the remaining ten populations ranked as susceptible according to the LD50R showed survival from 3.3 to 56% exposed to the lowest and from 0 to 17.7% exposed to the highest field rates of λ-cyhalothrin, respectively. Therefore, 50% of the tested E. connexa populations exhibited field-evolved resistance to λ-cyhalothrin and the use of a discriminatory LD50 for resistance matched the survival obtained when exposed to the insecticide field rates.
Field trials were conducted in 2013 and 2014 to investigate the tolerance of limpograss to increasing rates of hexazinone. Dose-response curves were generated using linear and quadratic regression models to determine the hexazinone estimated dose (ED) required to provide 10% (ED10) and 20% (ED20) of visual injury and herbage mass reduction. The ED10 and ED20 for visual estimates of injury were estimated to be 0.05 and 0.14 kg ai ha-1 at 60 d after treatment (DAT). Regarding forage herbage mass reduction, the ED10 and ED20 were estimated to be 0.07 and 0.19 kg ai ha-1 in 2013, whereas in 2014, the ED10 and ED20 were estimated to be 0.03 and 0.06 kg ai ha-1, respectively. The significant difference in herbage mass reduction between 2013 and 2014 was likely due to rainfall patterns, which possibly promoted hexazinone leaching in 2013 and consequently, less activity. Overall, hexazinone resulted in high degrees of limpograss injury across all response variables in both years; therefore, smutgrass control in limpograss pastures with hexazinone may not be a viable option. The presence or absence of smutgrass should be considered before limpograss establishment as there is no viable herbicide to selectively remove smutgrass from limpograss swards.
A wide-stopband bandpass-filtering power divider with high-frequency selectivity has been proposed in this paper. The input and output feeding lines and eight 1/4 wavelength resonators are used to realize the signal transmission. In order to obtain good frequency selectivity, source-load coupling transmission path is used to generate transmission zeros near the passband. A four-way power divider with bandpass-filtering response and high-frequency selectivity is designed, fabricated, and measured. The measured results agree with the simulated ones closely in the desirable frequency range. The measured center frequency of the power divider is 2.38 GHz with input return loss of 31.2 dB, while the measured insertion loss is about 1 dB (not including ideal 6 dB four-way power dividing insertion loss). Moreover, the measured 3-dB bandwidth is 12% and the measured stopband attenuation is >15 dB from 2.59 to 7.7 GHz. In addition, two transmission zeros of 1.9 and 2.8 GHz are located near the passband. The measured output isolations are all >15.7 dB.