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At least 19 recordsLinked to original sources
PubMed1995

Rapid angiographic progression of "target" and "nontarget" stenoses in patients awaiting coronary angioplasty.

OBJECTIVES: Our aim was to compare the short-term evolution of "target" versus "nontarget" stenoses in patients awaiting coronary angioplasty. BACKGROUND: Coronary angioplasty is effective therapy for angina pectoris, but coronary events occur after successful angioplasty that are caused by both restenosis and progression of mild preexisting nontarget stenoses. METHODS: We prospectively studied 161 consecutive patients with stable angina (124 men and 37 women). After diagnostic angiography, target stenoses for angioplasty and nontarget lesions were identified. Patients were put on a routine waiting list and followed up regularly until repeat coronary arteriography was performed (mean +/- SD 7 +/- 3 months), either immediately before angioplasty (138 patients) or soon after an acute coronary event (23 patients), if one occurred. Stenosis diameter was measured by using computerized arteriography. Progression of disease was defined as > or = 20% lesion diameter reduction, new total occlusion or development of a "new" stenosis > or = 30%. RESULTS: At study entry, the mean diameter of target (n = 207) and nontarget (n = 184) lesions was 68 +/- 9% and 38 +/- 9%, respectively (p < 0.001). Disease progression occurred in 33 patients (20%). Seven new lesions (one total occlusion) developed. Eighteen target (9%) and 15 nontarget (8%) stenoses progressed. The power of the study to detect a difference of 1% between the risks of progression of target and nontarget stenoses with a 90% probability was < 0.1. Total occlusion developed in 15 (83%) of the 18 target and 6 (40%) of the 15 nontarget stenoses (p = 0.03). During follow-up, a myocardial infarction developed in 3 patients (2%) and unstable angina in 20 (12%). These coronary events were associated with progression of target stenoses in 10 patients and nontarget stenoses in 7 and with the development of new lesions in 1. In five patients coronary events were not associated with stenosis progression. CONCLUSIONS: Despite differences in baseline severity, a similar proportion of target and nontarget lesions progressed rapidly. However, target stenoses were more likely than nontarget lesions to progress to total occlusion. Progression of nontarget stenoses may contribute to recurrence of angina and new coronary events after successful angioplasty and should be considered when developing strategies aimed at improving outcome after angioplasty.

Aged↗
PubMed1979

Depth of nontarget processing in an attention task.

Two studies examined the effect of the sensory discriminability of targets from nontargets on depth of nontarget processing. Subjects shadowed target words that were binaurally presented with coincident nontarget words. Targets and nontargets were spoken in the same male voice under low sensory discriminability and in male and female voices, respectively under high sensory discriminability. Across the two studies, depth of nontarget processing was assessed in three ways: extent to which shadowing accuracy was disrupted by a semantic overlap between targets and nontargets, expenditure of capacity (reaction time to subsidiary light signals), and nontarget recall. All three possible measures of depth of nontarget processing decreased as sensory discriminability increased. The data support the assumption of multiple-loci theories of attention that nontargets can be perceptually inhibited; they contraindicate the assumption of late-selection theories that perceptual processing is automatic and irrepressible.

Attention↗
PubMed1994

The relationship between time of arrival of nontargets and their spatial location: evidence for asymmetries in visual attentional processing.

A brief advance of the presentation of distant nontargets has previously been shown to secure them an analysis, suggesting that even stimuli beyond the putative 'spotlight' of attention are analysed. In the present experiment nontargets were presented near to fixation or peripherally (at 0.6 or 1.9 deg of visual angle) for a duration of 17, 33, or 67 ms before being masked. After a subsequent period (SOA) of 0, 20, 40, 60, or 80 ms the target was presented at fixation. The results from the shortest nontarget duration show a time lag in the development of the effect of far nontargets on response to the target. At durations of 33 and 67 ms the identity of far nontargets has been established before masking takes place, since their effect is observable at zero SOA. However, while this effect remains relatively constant over SOAs of 20 to 80 ms it increases with SOA in the near condition, suggesting that, although both near and far nontargets have been identified, it is only the near nontargets which are subject to further processing during the interval between nontarget and target presentations. The results favour a model of attention in which stimuli are passively selected and subject to additional processing on the basis of their spatial location rather than that the location or representation of distractor items are actively suppressed.

Adult↗
PubMed1998

What is learned about nontarget items in simple visual search?

Human sensitivity to correlational structure between nontargets and likelihood of target presence in a visual letter-search task were studied in two experiments. In each of these experiments, the performance of subjects for whom the nontarget information was altered in the final trial block was compared with the performance of subjects for whom the nontarget information did not change. When stimulus strings were presented individually on a computer screen and subjects were required to make a yes-no decision about target presence (Experiment 1), the change in nontarget structure resulted in increased reaction times for target-absent trials. When subjects searched simultaneously for three possible targets (Experiment 2), the change in nontarget structure produced increased error rates and increased reaction times for both target-absent and target-present trials. Correlations between the amount of predictive information in individual stimulus strings and reaction times also showed that both switching and nonswitching subjects were sensitive to the nontarget context. However, neither self-reports of strategy nor postexperiment choices between context-consistent and-inconsistent letter strings indicated any explicit knowledge of the predictive information in the nontarget stimuli. Subjects can thus acquire and benefit from, apparently without awareness, information about subtle correlational structure in nontarget elements in simple visual search.

Discrimination Learning↗
PubMedDate not supplied

Facilitatory or inhibitory nontarget effects in the location-cuing paradigm.

The effect of nontargets on the identification of targets in the location-cuing paradigm was investigated in order to determine whether observers consistently allocate their attention to a validly cued location and whether the effect of nontargets is to facilitate or to inhibit performance. In four experiments, the effects of a single matching nontarget or a single nonmatching nontarget were compared. In each experiment, it was shown that observers consistently allocate their attention to a cued location when a precue appears and that performance is inhibited more by nonmatching nontargets in the display than it is facilitated by matching nontargets.

Adult↗
PubMed1987

Spatial factors in visual attention: some compensatory effects of location and time of arrival of nontargets.

It is well established that the identity of nontarget events may affect reaction to a target event, but that spatial separation between the two will reduce such an influence. Two experiments are reported in which an attempt was made to distinguish between two accounts of this effect. On one, some of the information about events spatially distant from the target is shut out from analysis altogether. On the other, such events are fully analysed, but either the analysis proceeds more slowly or else it starts only after a delay. In the experiments the time of arrival of, and the distance between, the target and nontarget events were systematically varied. The conventional effects of the distance of nontargets from target were greatly reduced when the target and nontarget events were asynchronous. If the nontargets arrived first, they had an effect on reaction to the target whether they were near to or far from it. If they arrived second, their identity had no effect at either separation. These results appear to rule out any simple view of attention according to which information outside the target region is denied analysis. Rather, distant nontarget events are analysed, but produce their effects at a later time than less peripheral events.

Adolescent↗
PubMed1997

Facilitatory or Inhibitory Nontarget Effects in the Location-Cuing Paradigm

The effect of nontargets on the identification of targets in the location-cuing paradigm was investigated in order to determine whether observers consistently allocate their attention to a validly cued location and whether the effect of nontargets is to facilitate or to inhibit performance. In four experiments, the effects of a single matching nontarget or a single nonmatching nontarget were compared. In each experiment, it was shown that observers consistently allocate their attention to a cued location when a precue appears and that performance is inhibited more by nonmatching nontargets in the display than it is facilitated by matching nontargets.

Journal Article↗
PubMed2006

Structural identification of highly polar nontarget contaminants in drinking water by ESI-FAIMS-Q-TOF-MS.

Drinking water is a complex mixture that contains thousands of naturally occurring and anthropogenic contaminants. Liquid chromatography-mass spectrometry (LC-MS) methods have gained a tremendous popularity in monitoring nonvolatile, highly polar, and thermally labile components in drinking water. It is well recognized, however, that there are difficulties or limitations of LC-MS methods associated with (1) significant resources (time and effort) involved in sample preparation (preconcentration, fractionation, separation), (2) low screening capacity for target contaminants, and (3) insufficient capabilities for structural identification (elucidation) of nontarget contaminants. Consequently, LC-MS methods are mainly used for the detection of target contaminants (compounds identified in drinking water before), seldom for the structural identification of abundant nontarget pollutants (unidentified pollutants in drinking water), and almost never for the structural identification of nontarget components at a trace level. The paper presents a new method of electrospray ionization high field asymmetric waveform ion mobility spectrometry mass spectrometry (ESI-FAIMS-MS), which can detect a large number of water pollutants in a quick and convenient fashion without preconcentration, fractionation, derivatization, or column separation. Most importantly, the method provides structural identification of nontarget contaminants including species present in drinking water at a sub-parts-per-billion concentration level. The identification of previously unknown contaminants was based on mass measurements of investigated ions and their fragments in mass and tandem mass spectrometry. Elemental compositions of these ions, determined by mass measurements, were used to link dissociation patterns of investigated species with their chemical structures. Characterization of nontarget contaminants of chlorine-treated drinking water by ESI-FAIMS-MS has revealed many previously unknown disinfection byproducts. The most intriguing compound, from a group of highly polar hydroxycarboxylic acids discovered in the study, was the most abundant component of drinking water, glycolic acid. Glycolic acid (toxic to kidneys and associated with a moderate maternal toxicity) has never been considered as a drinking water contaminant, despite the fact that it is present in drinking water at a higher concentration (high ppm) than concentrations of highly polar water pollutants that had attracted most attention in the past. The process of structural elucidation of discovered pollutants, including ultratrace contaminants representing a variety of carboxylic acids, will be presented in detail. The structural identification of highly polar contaminants in drinking water presented in the paper is rarely reported in the literature. The key experimental feature of the ESI-FAIMS-MS method is FAIMS separation, which significantly improves the identification capabilities of mass spectrometry.

Molecular Structure↗
PubMed2006

Target-nontarget similarity modulates stimulus-driven control in visual search.

The literature contains conflicting results concerning whether an irrelevant featural singleton (an item unique with respect to a feature such as color or brightness) can control attention in a stimulus-driven manner. The present study explores whether target-nontarget similarity influences stimulus-driven shifts of attention to a distractor. An experiment evaluated whether manipulating target-nontarget similarity by varying orientation would modulate distraction by an irrelevant feature (a bright singleton). We found that increasing target-nontarget similarity resulted in a decreased impact of a uniquely bright object on visual search. This method of manipulating the target-nontarget similarity independent of the salience of a distracting feature suggests that the extent to which visual attention is stimulus-driven depends on the target-nontarget similarity.

Attention↗
PubMed1992

Perceptual processing of adjacent and nonadjacent tactile nontargets.

Previous research has shown that subjects appear unable to restrict processing to a single finger and ignore a stimulus presented to an adjacent finger. Furthermore, the evidence suggests that, at least for moving stimuli, an adjacent nontarget is fully processed to the level of incipient response activation. The present study replicated and expanded upon these original findings. The results of Experiment 1 showed that an equally large response-competition effect occurred when the nontarget was presented to adjacent and nonadjacent fingers (on the same hand). The results of Experiment 2 showed that the effects observed in Experiment 1 (and in previous studies) were also obtained with stationary stimuli. Although small, there was some indication in the results of Experiment 2 that interference may dissipate more rapidly with distance with stationary stimuli. An additional finding was that interference effects were observed in both experiments with temporal separations between the target and nontarget of up to 100 msec. In Experiment 3, target and nontarget stimuli were presented to opposite hands. Although reduced, interference was still evident with target and nontarget stimuli presented to opposite hands. Varying the physical distance between hands did not produce any change in the amount of interference. The results suggest that the focus of attention on the skin extends nearly undiminished across the fingers of one hand and is not dependent upon the physical distance between sites of stimulation.

Adult↗
PubMed2003

Operational note effects of fipronil and lambda-cyhalothrin against larval Anopheles quadrimaculatus and nontarget aquatic mosquito predators in Arkansas small rice plots.

The effects of fipronil and lambda-cyhalothrin, applied at rates labeled for control of the rice water weevil, Lissorhoptrus oryzophilus, on 3 nontarget indigenous insect species in Arkansas rice are described. Three replicates of untreated control checks and fipronil- and lambda-cyhalothrin-treated plots containing 3 sentinel cages each were performed. Ten 4th-stage larvae of Anopheles quadrimaculatus, 10 adult Tropisternus lateralis, or 10 adult Notonecta indica were placed within individual cages in small rice plots treated with ICON 6.2 FS (fipronil) at 0.025 lb active ingredient (AI)/acre (0.028 kg/ha) or KARATEZ 2.08 CS (lambda-cyhalothrin) at 0.03 lb AI/acre (0.033 kg/ha) applied over vegetation and water with a single-boom sprayer. At 24 h after treatment in fipronil plots, significantly higher control of An. quadrimaculatus and T. lateralis (69 and 48% control, respectively) was achieved, compared to N. indica (18%). In lambda-cyhalothrin plots 24 h after treatment, 100% reductions of both T. lateralis and N. indica were highly significant (P < 0.05) from the lower level of control in An. quadrimaculatus (10%). At 48 h after treatment, no significant, differences existed between all species within fipronil plots, with An. quadrimaculatus, T. lateralis, and N. indica obtaining 41, 10, and 7% control, respectively. Significantly higher (P < 0.05) control was obtained in lambda-cyhalothrin plots 48 h after treatment, with 93 and 53% control of T. lateralis and N. indica, respectively, compared to 7% control of An. quadrimaculatus. A marked difference in susceptibility was found between selected nontarget organisms used in this study. When using lambda-cyhalothrin to control adult L. oryzophilus, populations of nontarget beneficial insects, such as T. lateralis and N. indica, could be adversely affected, whereas nontarget pestilent species, such as An. quadrimaculatus, could proliferate. Fipronil achieved higher percentages of control against An. quadrimaculatus, compared to lambda-cyhalothrin, and was less harmful to both nontarget predators.

Agriculture↗
PubMed1998

Flavor avoidance learning and its implications in reducing strychnine baiting hazards to nontarget animals.

In reforested areas, underground strychnine baiting to control pocket gophers (Thomomys mazama) poses a hazard to golden mantled ground squirrels (Spermophilus lateralis) and yellow pine chipmunks (Eutamias amoenus). We designed this study to assess whether: 1) chemical insensitivity to bitter tastes might explain the ingestion of strychnine; 2) pocket gophers would avoid four bitter-tasting compounds: quebracho (QUEB), sucrose octaacetate (SOA), quinine hydrochloride (QHCl), and denatonium benzoate (DB); and 3) nontarget species could be trained to avoid strychnine paired with the most aversive compound. Our results showed that while all species readily consumed strychnine, the nontarget species could be conditioned to avoid it. Moreover, while high (0.1%) concentrations of DB, quinine hydrochloride, and quebracho reduced consumption by pocket gophers, 0.05% DB was inoffensive. Nontarget animals readily avoided 0.05% DB, and avoidance was stronger after conditioning. Together, our results suggest that all of the rodents tested are insensitive to strychnine, high concentrations of some bitter tastes may be effective pocket gopher repellents, and lower concentrations of DB may selectively repel nontarget animals from strychnine baits.

Animals↗
PubMed1991

Oligonucleotide site directed mutagenesis of all histidine residues within the T4 endonuclease V gene: role in enzyme-nontarget DNA binding.

In order to evaluate the contributions that histidine residues might play both in the catalytic activities of endonuclease V and in binding to nontarget DNA, the technique of oligonucleotide site directed mutagenesis was used to create mutations at each of the four histidine residues in the endonuclease V gene. Although none of the histidines were shown to be absolutely required for the pyrimidine dimer specific DNA glycosylase activity or the apurinic lyase activity, conservative amino acid changes at His16 produced enzymes with little or no catalytic activity. In addition, the evaluation of conservative and radical amino acid substitutions at positions 34, 56, and 107 is consistent with the interpretation that each of these histidines may be involved in nontarget DNA binding. The data supporting this conclusion are that histidine changes to lysine at positions 34 and 107 enhance the nontarget DNA binding activity of the mutant enzymes while neutralization of charge at His56 reduces nontarget DNA binding.

Base Sequence↗
PubMed2003

A sequential approach to risk assessment of transgenic plants expressing protease inhibitors: effects on nontarget herbivorous insects.

Protease inhibitors expressed in transgenic plants can provide enhanced levels of resistance to important pest species. A sequential approach for testing the effects of protease inhibitor-expressing crops on nontarget herbivorous insects has been developed. The approach consists of five tiers. The first two tiers comprise the selection phase. In tier one, field surveys are used to characterise the nontarget invertebrate fauna of a crop. In tier 2, histochemical assays are used to identify the subset of herbivores with a particular class of digestive proteolytic enzymes. In the assessment phase a combination of laboratory 'worst-case scenario' studies (tier 3) and controlled environment or small-scale field trials (tier 4) are used to evaluate the impact of the protease inhibitor-expressing plants on the selected nontarget species. In the final tier, field trials are used to compare the relative effect of transgenic plants and current management practices, such as pesticide use, on selected species. The first four tiers of the approach are described using potatoes expressing cystatins, a family of cysteine proteinase inhibitors, as an example. Although the plants have enhanced levels of resistance to potato cyst nematodes (PCN), Globodera pallida and Globodera rostochiensis, the results establish that they have negligible impact on the nontarget herbivorous insect, Eupteryx aurata.

Animals↗
PubMed2006

The associated non-targets effect: evidence of nontarget processing at and beyond the level of letter recognition.

In four visual search tasks participants were asked to make a target response if either of two targets was present and to make a nontarget response if neither target was present. Some target-absent displays included only nontarget stimuli or features that never occurred in the same displays as targets, whereas other target-absent displays included nontarget stimuli or features that did sometimes occur with targets. Nontarget responses were reliably faster in the former case than in the latter. This "associated non-targets effect" indicates that non-targets are not simply classified as non-targets but in addition are discriminated from one another. Current visual search models may underestimate the degree to which non-targets are processed during search.

Analysis of Variance↗
PubMed2005

Uptake of Bt endotoxins by nontarget herbivores and higher order arthropod predators: molecular evidence from a transgenic corn agroecosystem.

The planting of transgenic crops expressing Bacillus thuringiensis endotoxins is widespread throughout the world; the prolific increase in their application exposes nontarget organisms to toxins designed to control pests. To date, studies have focused upon the effects of Bt endotoxins on specific herbivores and detritivores, without consideration of their persistence within arthropod food webs. Here, we report the first quantitative field evaluation of levels of Bt endotoxin within nontarget herbivores and the uptake by higher order arthropods. Antibody-based assays indicated significant quantities of detectable Cry1Ab endotoxin within nontarget herbivores which feed on transgenic corn (including the corn flea beetle, Chaetocnema pulicaria, Japanese beetle, Popillia japonica and southern corn rootworm, Diabrotica undecimpunctata howardi). Furthermore, arthropod predators (Coccinellidae, Araneae, and Nabidae) collected from these agroecosystems also contained significant quantities of Cry1Ab endotoxin indicating its movement into higher trophic levels. This uptake by predators is likely to have occurred by direct feeding on plant material (in predators which are facultatively phytophagous) or the consumption of arthropod prey which contained these proteins. These data indicate that long-term exposure to insecticidal toxins occurs in the field. These levels of exposure should therefore be considered during future risk assessments of transgenic crops to nontarget herbivores and arthropod predators.

Agriculture↗
PubMed1990

Parietal P3 response as an indicator of stimulus categorization: increased P3 amplitude to categorically deviant target and nontarget stimuli.

Two experiments were performed in which we compared the effects of selected non-deviant versus categorically deviant stimuli on parietal P3 under a variety of conditions in which one, both, or neither stimulus was a target of an experimental task. Subjects were repeatedly presented with series of 8 numeric stimuli and 1 alphabetic (Deviant) stimulus. P3 amplitudes to target and nontarget Deviant stimuli were consistently and significantly larger than to other, non-deviant targets and nontargets, respectively. Nontarget Deviant stimuli evoked P3 amplitudes comparable to those evoked by low-probability non-deviant targets. The observed differences indicate that P3 amplitude is a sensitive indicator of perceived category differences, and that the effect of category deviance on parietal P3 amplitude is independent of task response classification (target or nontarget) and of response probability.

Adolescent↗
PubMed2003

Nontarget insects captured in fruit fly (Diptera: Tephritidae) surveillance traps.

Traps baited with synthetic lures (ammonium acetate and putrescine) captured as many Mexican fruit flies as the traditional torula yeast/borax slurry, but with far fewer (ratio 5:1) nontarget insects. Ninety percent of the nontarget insects were dipterans. Consequently, neither trap is efficacious against other citrus pests, which are mainly Hemiptera or Lepidoptera. Although the nontarget catch is sometimes referred to as "trash," many nontarget insects are beneficials, including predators and parasites (especially tachinids). The traps with synthetic lures killed fewer of these beneficials by a ratio of 4:1 compared with the yeast-baited traps. Certain taxa, notably the chrysopids and halictid bees, exhibited a somewhat greater preference (10 and 50%, respectively) for the synthetic lures. Overall, with regard to the deployment of the newer baits, the threat to predators, parasites, and pollinators was found to be negligible, and certainly much less than that posed by the traditional traps.

Acetates↗