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In his well-known autobiographical essay, “Trotsky and the Wild Orchids,” Rorty observed two contrasting dispositions that he developed as a young boy. On the one hand, as the son of two radical, fellow-traveling Trotskyists, he absorbed a firm commitment to social justice and democratic politics. At the same time, as a solitary, even lonely child, living in rural isolation, he also had “private, weird, snobbish, incommunicable interests,” such as an obsession with various species of wild orchids that grew near his home in northwest New Jersey. Much has been written about Rorty’s politics, about his “Trotsky” side. But relatively little has been said about his encounters with wild orchids, “Wordsworthean moments” in which he felt “touched by something numinous, something of ineffable importance.” Rorty said “there is no reason to be ashamed of, or downgrade, or try to slough off, your Wordsworthean moments.” Yet no one said less about these moments than Rorty himself; he seemed to slough them off. Why? My argument is that even acknowledging having had such moments (which he rarely did) seemed to him to pose a threat to his antifoundationalism, to his remarkably extreme view of human autonomy, and to his resolutely anti-authoritarian temperament. Alas.
Striking a balance between the weed control capacity of living mulches and their competition with the main crop is complex. At rates that avoid severe injury to living mulch, herbicides may reduce their vigor while simultaneously contributing to weed control. In a 2-yr field study carried out in Freeville, NY, we evaluated the effects of various combinations consisting of two herbicides, applied sequentially at reduced rates, on the growth of a sunn hemp living mulch and weeds (including common lambsquarters, common purslane, hairy galinsoga, and Powell amaranth). When a herbicide with primarily POST activity (Type 1; e.g., rimsulfuron, 0.005 to 0.007 kg ai ha−1) was applied first, performance of sunn hemp (1700 to 3900 kg ha−1 dry biomass; 10% to 88% groundcover) was poor and weed growth (25% to 62% groundcover) was high, likely because sunn hemp was severely injured at a young growth stage and was outcompeted by weeds. A follow-up application (approximately 2 wk later) of a herbicide with primarily PRE and residual activities (Type 2; e.g., metribuzin, 0.05 to 0.15 kg ai ha−1), with a surfactant to enhance its POST activity, had little effect on established weeds. However, because sunn hemp was already 20 cm tall at weed emergence, applying a Type 2 herbicide first did not cause severe injury to sunn hemp and reduced weed pressure, thereby also enhancing sunn hemp performance (3,800 to 6,100 kg ha−1 dry biomass; 85% to 94% groundcover). Moreover, the follow-up application of a Type 1 herbicide affected the smaller weeds more (4% to 21% groundcover) than the better-established sunn hemp. Our results demonstrate that an appropriate sequence of herbicides at reduced rates may be important to control weeds while maintaining a healthy living mulch stand.
Macronutrient inputs to annual cropping systems can benefit weeds as well as crops, sometimes decreasing or eliminating the benefits of fertilization. This interaction between fertility management and integrated weed management is becoming increasingly important as these fields increase their focus on efficiency and prevention, respectively. The risk of increased weed competition reflects the fact that weed biomass and height may be highly responsive to nitrogen, phosphorus, and/or potassium. This generalization is supported by monoculture studies of species such as redroot pigweed (Amaranthus retroflexus L.), common lambsquarters (Chenopodium album L.), and barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.] and by ecological theory. However, field studies indicate variation in the effects of macronutrients on weed–crop competition and crop yield, even within species groups. To address challenges in interpreting, comparing, and extrapolating from these diverse reports, we propose a conceptual framework that summarizes the mechanisms underlying observed variation within and between studies. This framework highlights functional traits and trends that help predict yield outcomes in binary weed–crop interactions. Important factors include timing of emergence, maximum heights of the weed and crop, and relative responsiveness to the added nutrient. We also survey recent work on the effects of nutrient source (e.g., the composition of organic amendments) on weed–crop competition. Because different sources vary in their nutrient release dynamics and supplied nutrient ratios, they may have dramatically different effects on weed–crop competition and crop yield. Finally, we offer a guide to best practices for studies of fertility effects on weed–crop competition. Although this review highlights several topics requiring further research, including fertility effects on multispecies interactions and interactions with other environmental factors, emerging methods offer considerable promise. Ultimately, an improved understanding of nutrient effects on weed–crop competition will contribute to the efficient and effective management of diverse cropping systems.
The introduced meadow knapweed (Centaurea × moncktonii C.E. Britton), a hybrid of black (Centaurea nigra L.) and brown (Centaurea jacea L.) knapweeds, is increasingly common in pastures, meadows, and waste areas across many U.S. states, including New York. We evaluated the effects of temperature, light, seed stratification, scarification, and population on percent germination in four experiments over 2 yr. Percent germination ranged from 3% to 100% across treatment combinations. Higher temperatures (30:20, 25:15, and sometimes 20:10 C day:night regimes compared with 15:5 C) promoted germination, especially when combined with the stimulatory effect of light (14:10 h L:D compared with continuous darkness). Under the three lowest temperature treatments, light increased percent germination by 15% to 86%. Cold-wet seed stratification also increased germination rates, especially at lower germination temperatures, but was not a prerequisite for germination. Scarification did not increase percent germination. Differences between C. × moncktonii populations were generally less significant than differences between temperature, light, and stratification treatments. Taken together, these results indicate that C. × moncktonii is capable of germinating under a broad range of environments, which may have facilitated this species’ range expansion in recent decades. However, C. × moncktonii also shows evidence of germination polymorphism: some seeds will germinate under suboptimal conditions, while others may remain dormant until the abiotic environment improves. Subtle differences in dormancy mechanisms and their relative frequencies may affect phenological traits like the timing of seedling emergence and ultimately shape the sizes and ranges of C. × moncktonii populations.
Abnormal effort-based decision-making represents a potential mechanism underlying motivational deficits (amotivation) in psychotic disorders. Previous research identified effort allocation impairment in chronic schizophrenia and focused mostly on physical effort modality. No study has investigated cognitive effort allocation in first-episode psychosis (FEP).
Cognitive effort allocation was examined in 40 FEP patients and 44 demographically-matched healthy controls, using Cognitive Effort-Discounting (COGED) paradigm which quantified participants’ willingness to expend cognitive effort in terms of explicit, continuous discounting of monetary rewards based on parametrically-varied cognitive demands (levels N of N-back task). Relationship between reward-discounting and amotivation was investigated. Group differences in reward-magnitude and effort-cost sensitivity, and differential associations of these sensitivity indices with amotivation were explored.
Patients displayed significantly greater reward-discounting than controls. In particular, such discounting was most pronounced in patients with high levels of amotivation even when N-back performance and reward base amount were taken into consideration. Moreover, patients exhibited reduced reward-benefit sensitivity and effort-cost sensitivity relative to controls, and that decreased sensitivity to reward-benefit but not effort-cost was correlated with diminished motivation. Reward-discounting and sensitivity indices were generally unrelated to other symptom dimensions, antipsychotic dose and cognitive deficits.
This study provides the first evidence of cognitive effort-based decision-making impairment in FEP, and indicates that decreased effort expenditure is associated with amotivation. Our findings further suggest that abnormal effort allocation and amotivation might primarily be related to blunted reward valuation. Prospective research is required to clarify the utility of effort-based measures in predicting amotivation and functional outcome in FEP.
The Language Teachers’ Target Language project (LTTL) aims to describe language teachers’ target language use domain (Bachman & Palmer 2010) and to develop a language test for future teachers of English. The team comprises four researchers from Moscow State University (MSU) and Southampton Solent University.
Many individuals who sustain moderate–severe traumatic brain injuries (TBI) are poor at recognizing emotional expressions, with a greater impairment in recognizing negative (e.g., fear, disgust, sadness, and anger) than positive emotions (e.g., happiness and surprise). It has been questioned whether this “valence effect” might be an artifact of the wide use of static facial emotion stimuli (usually full-blown expressions) which differ in difficulty rather than a real consequence of brain impairment. This study aimed to investigate the valence effect in TBI, while examining emotion recognition across different intensities (low, medium, and high).
Method: Twenty-seven individuals with TBI and 28 matched control participants were tested on the Emotion Recognition Task (ERT). The TBI group was more impaired in overall emotion recognition, and less accurate recognizing negative emotions. However, examining the performance across the different intensities indicated that this difference was driven by some emotions (e.g., happiness) being much easier to recognize than others (e.g., fear and surprise). Our findings indicate that individuals with TBI have an overall deficit in facial emotion recognition, and that both people with TBI and control participants found some emotions more difficult than others. These results suggest that conventional measures of facial affect recognition that do not examine variance in the difficulty of emotions may produce erroneous conclusions about differential impairment. They also cast doubt on the notion that dissociable neural pathways underlie the recognition of positive and negative emotions, which are differentially affected by TBI and potentially other neurological or psychiatric disorders. (JINS, 2014, 20, 1–10)
If cognitive effort indexes opportunity costs, it should be investigated like other cost factors including risk and delay. We discuss recent methodological advances in behavioral economics and neuroeconomics, highlighting our own work in measuring the subjective (economic) value of cognitive effort. We discuss the implications of Kurzban et al.'s proposal and how some of its predictions may be untestable without behavioral economic formalisms.
Both HIV infection and high levels of early life stress (ELS) have been related to abnormalities in frontal-subcortical structures, yet the combined effects of HIV and ELS on brain structure and function have not been previously investigated. In this study we assessed 49 non-demented HIV-seropositive (HIV+) and 47 age-matched HIV-seronegative healthy control (HC) adults. Levels of ELS exposure were quantified and used to define four HIV-ELS groups: HC Low-ELS (N = 20); HC High-ELS (N = 27); HIV+ Low-ELS (N = 24); HIV+ High-ELS (N = 25). An automated segmentation tool measured volumes of brain structures known to show HIV-related or ELS-related effects; a brief neurocognitive battery was administered. A significant HIV-ELS interaction was observed for amygdala volumes, which was driven by enlargements in HIV+ High-ELS participants. The HIV+ High-ELS group also demonstrated significant reductions in psychomotor/processing speed compared with HC Low-ELS. Regression analyses in the HIV+ group revealed that amygdala enlargements were associated with higher ELS, lower nadir CD4 counts, and reduced psychomotor/processing speed. Our results suggest that HIV infection and high ELS interact to increase amygdala volume, which is associated with neurocognitive dysfunction in HIV+ patients. These findings highlight the lasting neuropathological influence of ELS and suggest that high ELS may be a significant risk factor for neurocognitive impairment in HIV-infected individuals. (JINS, 2012, 19, 1–12)
HIV-associated neurocognitive dysfunction persists in the highly active antiretroviral therapy (HAART) era and may be exacerbated by comorbidities, including substance use and hepatitis C virus (HCV) infection. However, the neurocognitive impact of HIV, HCV, and substance use in the HAART era is still not well understood. In the current study, 115 HIV-infected and 72 HIV-seronegative individuals with significant rates of lifetime substance dependence and HCV infection received comprehensive neuropsychological assessment. We examined the effects of HIV serostatus, HCV infection, and substance use history on neurocognitive functioning. We also examined relationships between HIV disease measures (current and nadir CD4, HIV RNA, duration of infection) and cognitive functioning. Approximately half of HIV-infected participants exhibited neurocognitive impairment. Detectable HIV RNA but not HIV serostatus was significantly associated with cognitive functioning. HCV was among the factors most consistently associated with poorer neurocognitive performance across domains, while substance use was less strongly associated with cognitive performance. The results suggest that neurocognitive impairment continues to occur in HIV-infected individuals in association with poor virologic control and comorbid conditions, particularly HCV coinfection. (JINS, 2012, 18, 68–78)
Background: Online CBT training is in its infancy. The initial studies have varied program characteristics and trainee groups, but results appear promising. At this stage, there is a need to evaluate programs with different characteristics to determine which are useful, and which are not. Method: This paper reports a preliminary evaluation of an online CBT training package, OCTC Online, which is distinguished from other online programs by its particularly strong focus on video presentations by trainers, accompanying PowerPoint slides, and video demonstrations of key clinical techniques. Participants (N = 94) completed online rating scales and questionnaires assessing (a) their satisfaction with the training; (b) their self-rated knowledge and confidence about the topics discussed (pre- and post-training); and (c) a multiple choice questionnaire (MCQ) objective test of knowledge (also pre- and post-training). Results: Results showed that on average students were highly satisfied with the online training modules, their self-rated confidence increased significantly, and so did their scores on the MCQ. Conclusions: The study has significant limitations but nevertheless contributes to the growing body of evidence that online training may have a useful part to play in enhancing therapists’ knowledge of CBT theory and techniques, and their confidence in using the techniques.
To those of us concerned with transnational law, and especially the role of German law on the global stage, it does not need saying that Professor Detlev Vagts is highly deserving of that Germanic and traditional scholarly honour, a Festchrift. (In this context, ‘does not need saying’ of course means ‘should be said repeatedly’.) We all owe Detlev Vagts, and as a Germanic traditionalist, I would be delighted to contribute to this volume on general principle, even if I did not know the man. But I also have personal reasons for wanting to honour Professor Vagts: he taught the basic course in corporations to generations of students at Harvard Law School. In addition, Vagts was one of the advisors to the Ford Fellows Program, which was designed to foster international law teachers. After being one such student and one such fellow, in due course I became a teacher of international and corporation law, so I owe Vagts a double debt of professional gratitude. And, as with so many other young (or once young) scholars, Vagts has been cordially supportive of my efforts to find my way in the academy, for which I am most grateful.
Such things said, however, there is another reason I am happy to have the chance to contribute to this Festschrift. A certain delicacy is called for here, especially since writing for Vagts carries me halfway back to Harvard, where such things are taken so seriously.
Characterized by frontostriatal dysfunction, human immunodeficiency virus (HIV) is associated with cognitive and psychiatric abnormalities. Several studies have noted impaired facial emotion recognition abilities in patient populations that demonstrate frontostriatal dysfunction; however, facial emotion recognition abilities have not been systematically examined in HIV patients. The current study investigated facial emotion recognition in 50 nondemented HIV-seropositive adults and 50 control participants relative to their performance on a nonemotional landscape categorization control task. We examined the relation of HIV-disease factors (nadir and current CD4 levels) to emotion recognition abilities and assessed the psychosocial impact of emotion recognition abnormalities. Compared to control participants, HIV patients performed normally on the control task but demonstrated significant impairments in facial emotion recognition, specifically for fear. HIV patients reported greater psychosocial impairments, which correlated with increased emotion recognition difficulties. Lower current CD4 counts were associated with poorer anger recognition. In summary, our results indicate that chronic HIV infection may contribute to emotion processing problems among HIV patients. We suggest that disruptions of frontostriatal structures and their connections with cortico-limbic networks may contribute to emotion recognition abnormalities in HIV. Our findings also highlight the significant psychosocial impact that emotion recognition abnormalities have on individuals with HIV. (JINS, 2010, 16, 1127–1137.)
Previous efficacy studies found that many insecticides used by growers could be having an adverse effect on egg parasitoids (Telenomus podisi) developing in the eggs of the brown stink bug (Euschistus servus), while unhatched stink bugs experienced lower levels of mortality. One plausible explanation for this was that insecticides might enter parasitized eggs more readily via oviposition wounds. Parasitized E. servus eggs, as well as nonparasitized stink bug (Acrosternum hilare, E. servus, Murgantia histrionica, and Podisus maculiventris) eggs, were examined using electron microscopy. Egg response to perforation by a tungsten probe served as a control. Microscopy images depicted the chorion surface as characterized by a matrix of ridges and micropylar processes in a ring around the margin of the operculum. Observations of oviposition sites showed a “scab” formed where the ovipositor penetrated the chorion, and at sites penetrated by the probe. These formations appeared to be the result of fluids from inside the egg leaking out, drying, and hardening after oviposition or probe perforation, suggesting that the response was not due to substances secreted by the parasitoid. Further, no open wounds or holes were seen to increase the possibility of insecticides entering parasitized eggs.
John Dewey's way of thinking about thinking invites the intellectual historian. We are scholars eager to put thought in its contexts: not only contexts internal to the history of philosophy but social, political, cultural, and biographical contexts. Dewey not only shared this impulse and wrote some provocative intellectual history himself, but provided the enterprise with philosophical underpinnings. Dewey argued that human beings were thinkers only in the second instance. In the first instance, he said, the self was “an agent-patient, doer, sufferer, and enjoyer.” Thinking emerged out of non-cognitive, “primary experience” and was in the service of controlling and enriching such experience. “To be a man,” Dewey argued, “is to be thinking desire.” In one of his most often-quoted remarks, he warned his fellow philosophers that they were losing sight of their cultural embodiment and that they were on the path to terminal marginality unless philosophy “ceases to be a device for dealing with the problems of philosophers and becomes a method, cultivated by philosophers, for dealing with the problems of men.” Positions such as these not only underwrite intellectual history. They also inevitably provoke the interest of intellectual historians in Dewey's own desires, his own primary experience, and his own engagement with the problems of those outside the narrow circle of professional philosophers. They alert the antennae of intellectual biographers.
The simplest way to study learning is to expose subjects to a stimulus and then assess whether they show some effect which is absent in subjects lacking that experience (see Rescorla, 1998). One stimulus exposure effect is latent inhibition. Subjects in one group but not another are exposed to a stimulus in the absence of any other scheduled event. Then subjects in both groups are exposed to a signaling relation between that stimulus (the conditioned stimulus (CS)) and a motivationally significant event (an unconditioned stimulus (US)). The responding elicited by the CS in subjects just exposed to the signaling relation is depressed in those pre-exposed to the stimulus. Conditioned responding is said to have been latently inhibited by the prior stimulus-alone exposures. This effect has also been observed in a within-subject design where subjects are first exposed to one stimulus but not to another and then to a signaling relation between each of these stimuli and a US. Responding develops more rapidly to the novel CS than to one that had been pre-exposed (e.g., Killcross & Robbins, 1993; Rescorla, 2002a, 2002b).
Another effect of stimulus exposures is extinction. Two groups of subjects are exposed to a signaling relation between a CS and US. Then subjects in one group but not the other are exposed to the CS in the absence of any other scheduled event. The responding elicited by the CS in subjects just exposed to the signaling relation is depressed in those that additionally received the CS-alone exposures.