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Citriculture landscapes in the U.S. are typically habitat mosaics of commercial groves interspersed with residential areas supporting a variety of unmanaged citrus. Diaphorina citri the vector of Candidatus Liberibacter asiaticus, the causal agent of Huanglongbing feeds on citrus in both habitats. We postulated that residential citrus function as a ‘source’ of D. citri that infest groves, functioning as sinks. Here we report on an experimental mark-release-recapture study conducted at the interface of a residential neighborhood and groves. Adult D. citri marked with colored fluorescent powders were released in both habitats (n = 15,300) and their movement within and between milieus monitored. Although the recapture rate of marked psyllids was very low (0.23%), the results were instructive. Most of the recaptured psyllids in residential trees (84.6%) were released within that habitat. In contrast, approximately half of the marked psyllids recovered in groves were released in residential areas. Of all the recaptured psyllids, about 40% changed habitats, but the change was skewed toward movement from residential to grove habitat. These data strongly suggest that there is a constant exchange of D. citri adults between the two habitats, with residential citrus trees functioning as a source habitat of psyllids. The further the residential trees are located from groves, the less likely they will serve as sources of D. citri. Hence, to reduce the risks of citrus grove colonization by D. citri, new groves should be established away from residential habitats where possible, and psyllid management practices must also be implemented in residential habitats.

The obligate pollination mutualism between Yucca and yucca moths is a classical example of coevolution. Oviposition and active pollination by female yucca moths occur at night when Yucca flowers are open and strongly scented. Thus, floral volatiles have been suggested as key sensory signals attracting yucca moths to their host plants, but no bioactive compounds have yet been identified. In this study, we showed that both sexes of the pollinator moth Tegeticula yuccasella are attracted to the floral scent of the host Yucca filamentosa. Chemical analysis of the floral headspace from six Yucca species in sections Chaenocarpa and Sarcocarpa revealed a set of novel tetranorsesquiterpenoids putatively derived from (E)-4,8-dimethyl-1,3,7-nonatriene. Their structure elucidation was accomplished by NMR analysis of the crude floral scent sample of Yucca treculeana along with GC/MS analysis and confirmed by total synthesis. Since all these volatiles are included in the floral scent of Y. filamentosa, which has been an important model species for understanding the pollination mutualism, we name these compounds filamentolide, filamentol, filamental, and filamentone. Several of these compounds elicited antennal responses in pollinating (Tegeticula) and non-pollinating (Prodoxus) moth species upon stimulation in electrophysiological recordings. In addition, synthetic (Z)-filamentolide attracted significant numbers of both sexes of two associated Prodoxus species in a field trapping experiment. Highly specialized insect-plant interactions, such as obligate pollination mutualisms, are predicted to be maintained through "private channels" dictated by specific compounds. The identification of novel bioactive tetranorsesquiterpenoids is a first step in testing such a hypothesis in the Yucca-yucca moth interaction.

A prevailing view in cognitive neuroscience suggests that different forms of learning are mediated by dissociable memory systems, with a mesolimbic (i.e., midbrain and basal ganglia) system supporting incremental trial-and-error reinforcement learning and a hippocampal-based system supporting episodic memory. Yet, growing evidence suggests that the hippocampus may also be important for trial-and-error learning, particularly value or reward-based learning. In the present report, we use a lesion-based neuropsychological approach to clarify hippocampal contributions to such learning. Six amnesic patients with medial temporal lobe damage and a group of healthy controls were administered a simple value-based learning task involving probabilistic trial-and-error acquisition of stimulus-response-outcome (reward or none) contingencies modeled after Li et al. (Proceedings of the National Academy of Sciences , 2011, 108 (1), 55-60). As predicted, patients were significantly impaired on the task, demonstrating reduced learning of the contingencies. Our results provide further supportive evidence that the hippocampus' role in cognition extends beyond episodic memory tasks and call for further refinement of theoretical models of hippocampal functioning.

Progressive supranuclear palsy (PSP) is primary 4-repeat tauopathy. Evidence spanning from imaging studies indicate aberrant connectivity in PSPs. Our goal was to assess functional connectivity network alterations in PSP patients and the potential link between regional tau-burden and network-level functional connectivity using the next-generation tau PET tracer [sup18/supF]PI-2620 and resting-state functional MRI (fMRI).Twenty-four probable PSP patients (70.9 ± 6.9 years, 13 female), including 14 Richardson syndrome (RS) and 10 non-RS phenotypes, underwent [sup18/supF]PI-2620 PET/MRI imaging. Distribution volume ratios (DVRs) were estimated using non-invasive pharmacokinetic modeling. Resting-state fMRI was also acquired in these patients as well as in thirteen older non-AD MCI reference group (64 ± 9 years, 4 female). The functional network was constructed using 141 by 141 region-to-region functional connectivity metrics (RRC) and network-based statistic was carried out (connection threshold p lt; 0.001, cluster threshold pFDR lt; 0.05).In total, 9870 functional connections were analyzed. PSPs compared to aged non-AD MCI reference group expressed aberrant connectivity evidenced by the significant NBS network consisting of 89 ROIs and 118 connections among them (NBS mass 4226, pFDR lt; 0.05). Tau load in the right globus pallidus externus (GPe) and left dentate nucleus (DN) showed significant effects on functional network connectivity. The network linked with increased tau load in the right GPe was associated with hyperconnectivity of low-range intra-opercular connections (NBS mass 356, pFDR lt; 0.05), while the network linked with increased tau load in the left cerebellar DN was associated with cerebellar hyperconnectivity and cortico-cerebellar hypoconnectivity (NBS mass 517, pFDR lt; 0.05).PSP patients show altered functional connectivity. Network incorporating deep gray matter structures demonstrate hypoconnectivity, cerebellum hyperconnectivity, while cortico-cortical connections show variable changes. Tau load in the right GPe and left DN is associated with functional networks which strengthen low-scale intra-opercular and intra-cerebellar connections and weaken opercular-cerebellar connections. These findings support the concept of tau load-dependent functional network changes in PSP, by that providing evidence for downstream effects of neuropathology on brain functionality in this primary tauopathy.

This study confirmed that some glues used for trapping insects may inhibit mycosis; therefore, care should be taken to select “mycosis-friendly” glues when selecting sticky traps for monitoring entomopathogen infection levels in target pest populations. The results also showed that, rather than attempting to extract small, delicate insects from the glue for further incubation, the entire sticky trap simply can be incubated for the purpose of evaluating mycosis levels.

When faced with intertemporal choices, people typically devalue rewards available in the future compared to rewards more immediately available, a phenomenon known as temporal discounting. Decisions involving intertemporal choices arise daily, with critical impact on health and financial wellbeing. Although many such decisions are “experiential” in that they involve delays and rewards that are experienced in real-time and can inform subsequent choices, most studies have focused on intertemporal choices with hypothetical outcomes (or outcomes delivered after all decisions are made). The present study focused on experiential intertemporal choices. First, a novel intertemporal choice task was developed and validated, using delays experienced in real time and artistic photographs as consumable perceptual rewards. Second, performance on the experiential task was compared to performance on a classic intertemporal choice task with hypothetical outcomes. Involvement of distinct processes across tasks was probed by examining differential relations to trait anxiety and state anxiety. A two-parameter logistic function framework was proposed to fit indifference point data, and was shown to improve upon hyperbolic fit. This approach accounts for individual variability not only in the delay at which an individual switches from choosing the delayed to more immediate option, but also in the slope of that switch. Fit results indicated that the experiential task elicited temporal discounting, with effective trade-off between delay and perceptual reward. Comparison with the hypothetical intertemporal choice task suggested distinct mechanisms: temporal discounting across the two tasks was not correlated; state anxiety affected choice behavior in the experiential task but not in the hypothetical task; and trait anxiety had contrasting effects across the two tasks. These findings were interpreted as reflecting differential engagement of episodic processes in the experiential compared to the hypothetical task, consistent with neural evidence for recruitment of the hippocampus in the former but not in the latter task.

Fibroblast growth factor 21 (FGF21) is a regulator of addictive behavior. Increasing evidence suggests an impact of FGF21 on eating behavior, food and drug cravings and on other adipokines like insulin-like growth factor 1 (IGF-1) or adiponectin. We investigated the association of serum FGF21 and genetic variants with aspects of food and drug craving and obesity related metabolic parameters including serum adipokine levels. Standardized questionnaires, blood samples and anthropometric data of the Sorbs cohort (n = 1046) were analyzed using SPSS. For genetic analyses, the FGF21-locus ±10 kb was genotyped and analyzed using PLINK. Validation was conducted in a second independent cohort (n = 704). FGF21 was significantly associated with alcohol and coffee consumption, smoking and eating behavior (disinhibition). We confirmed correlations of FGF21 serum levels with IGF-1, adiponectin, pro-enkephalin, adipocyte fatty-acid-binding protein, chemerin and progranulin. FGF21 genetic variants were associated with anthropometric and metabolic parameters, adipokines, food and drug craving while strongest evidence was seen with low-density lipoprotein cholesterol (LDL-C). We highlight the potential role of FGF21 in food and drug cravings and provide new insights regarding the link of FGF21 with other adipokines as well as with metabolic traits, in particular those related to lipid metabolism (LDL-C).

Eine intakte Darmbarriere ist die Schnittstelle zwischen Umwelt‑, Verhaltens- und intrinsisch biologischen Faktoren und stellt einen wesentlichen Parameter der Integritat eines gesunden Organismus dar. Neben ihrer Rolle in einer Vielzahl physiologischer Prozesse kann die Darmmikrobiota zur Beeintrachtigung der Darmbarriere und Veranderung der intestinalen Permeabilitat beitragen. Letztere wird sowohl uber exogene Faktoren wie Ernahrung, Alkohol, Medikamenteneinnahme und pathogene Bakterien als auch uber korpereigene Mechanismen, die z. B. durch veranderte Immunabwehr oder gestorte Glukosetoleranz getriggert werden, reguliert. Aufgrund einer erhohten Darmpermeabilitat gelangen verstarkt Bakterien sowie deren Bestandteile in den Kreislauf, was systemisch zur Aggravation einer bestehenden Adipositas sowie einer zunehmenden Insulinresistenz bis hin zu kardiovaskularen Ereignissen beitragen kann. Auserdem kommt es auf der Ebene von Organen und Geweben durch die erhohte bakterielle Exposition zu einem circulus vitiosus, in dem uber eine Schadigung der lokalen Abwehr mit weiterer Erhohung der Darmpermeabilitat eine lokale inflammatorische Aktivierung entsteht, die einen systemischen proinflammatorischen, diabetogenen und atherogenen Status unterhalt. Die Modulation der Darmpermeabilitat durch Ernahrung und andere Interventionen, einschlieslich Manipulation des Darmmikrobioms durch Pra‑, Pro- oder Synbiotika, stellt ein potenzielles Praventions- und Behandlungsziel fur kardiometabolische Erkrankungen dar, das aber derzeit in der klinischen Praxis noch kaum eine Rolle spielt. Voraussetzung fur eine gezielte Therapie, die Veranderungen des Mikrobioms bewirken soll, ist ein besseres Verstandnis der Wechselwirkungen zwischen Mikrobiota und kardiometabolischen Erkrankungen.

Most commercial citrus varieties are intolerant of salinity stress, but some rootstocks, such as Rangpur lime, tolerate moderately saline irrigation water. Development of salinity-tolerant citrus may allow for citriculture in semiarid and arid regions where salinity stress is problematic. Because salinity stress influences shoot growth in citrus, we compared the behavioral responses of Asian citrus psyllid, Diaphorina citri Kuwayama, to salinity-stressed versus nonstressed Rangpur lime seedlings. The effects of salinity stress on key physiological processes in the seedlings were also examined. Seedlings in the control group were fertilized with a solution having a salinity of 1.7 dS m−1 while seedlings in the salinity-stressed group were fertilized with a solution having a salinity of 10 dS m−1. The seedlings were exposed to salinity stress for increasing durations (15, 20, or 60 d). Seedlings presented differential physiological responses 15 d after the imposition of salinity stress, and differences in psyllid settling rate on control versus salinity-stressed seedlings were discernable within 1 h following the imposition of salinity stress. The levels of settling, oviposition, and egg survivorship were significantly lower on salinity-stressed versus control seedlings. Olfactometer tests showed that female psyllids preferred the odor from control seedlings, suggesting that the odors of control and salinity-stressed seedlings were different. The results showed that D. citri avoids salinity-stressed seedlings; this suggests the possibility of using moderate salinity stress as a management strategy to minimize psyllid settlement and reproduction and to reduce the spread of huanglongbing, especially in citrus grown in semiarid and arid areas.

The adaptation of experimental cognitive tasks into measures that can be used to quantify neurocognitive outcomes in translational studies and clinical trials has become a key component of the strategy to address psychiatric and neurological disorders. Unfortunately, while most experimental cognitive tests have strong theoretical bases, they can have poor psychometric properties, leaving them vulnerable to measurement challenges that undermine their use in applied settings. Item response theory–based computerized adaptive testing has been proposed as a solution but has been limited in experimental and translational research due to its large sample requirements. We present a generalized latent variable model that, when combined with strong parametric assumptions based on mathematical cognitive models, permits the use of adaptive testing without large samples or the need to precalibrate item parameters. The approach is demonstrated using data from a common measure of working memory—the N-back task—collected across a diverse sample of participants. After evaluating dimensionality and model fit, we conducted a simulation study to compare adaptive versus nonadaptive testing. Computerized adaptive testing either made the task 36% more efficient or score estimates 23% more precise, when compared to nonadaptive testing. This proof-of-concept study demonstrates that latent variable modeling and adaptive testing can be used in experimental cognitive testing even with relatively small samples. Adaptive testing has the potential to improve the impact and replicability of findings from translational studies and clinical trials that use experimental cognitive tasks as outcome measures.

Summary Adding plant-based nutritional resources to a landscape may help to recruit and retain predaceous and parasitic arthropods. As a first step in determining whether the addition of nectary plants can increase the abundance and diversity of biocontrol agents of Diaphorina citri and psyllid suppression in urban and unmanaged landscapes in southern Florida, the occurrence of coccinellids was recorded on a native poinsettia, Euphorbia heterophylla (L.) and partridge pea, Chamaecrista fasciculata (Michx.) Greene, a native legume. Thirteen coccinellid species consisting of a total of 663 specimens were collected over the course of the 8-mo long sampling period. A total of 464 specimens comprising 12 species were collected from E. heterophylla from Jun to Oct, with 3 species, Coelophora inequalis , Cryptolaemus montrouzieri , Harmonia axyridis , comprising the majority of species collected. A total of 199 specimens comprising 6 species were collected from C . fasciculate from Sep to Feb. Nearly 80% of the specimens collected from C. fasciculata were C. montrouzieri . Sumario La adicion de recursos nutricionales a base de plantas a un paisaje puede ayudar a reclutar y retener a los artropodos predadores y parasitarios. Como primer paso para determinar si la adicion de plantas nectarias puede aumentar la abundancia y diversidad de agentes de control biologico de Diaphorina citri y la supresion de psilidos en paisajes urbanos y no manejados en el sur de la Florida, se registro la presencia de coccinelidos en una natividad nativa, Euphorbia heterophylla L.) y perdiz, Chamaecrista fasciculata (Michx.) Greene, una leguminosa nativa. Trece especies de coccinelidos consistentes en un total de 663 especimenes fueron recolectadas durante el periodo de muestreo de 8 meses. Un total de 464 especimenes que comprenden 12 especies fueron recolectadas de E. heterophylla de jun a oct, con 3 especies, Coelophora inequalis , Cryptolaemus montrouzieri , Harmonia axyridis , que comprende la mayoria de las especies recogidas. Un total de 199 especimenes que comprenden 6 especies se recogieron de C. fasciculate de sep a feb. Casi el 80% de los especimenes recolectados de C. fasciculata fueron C. montrouzieri . View this article in BioOne

The relationship between food-intake related behaviours measured by the Three-Factor Eating Questionnaire (TFEQ) and in vivo norepinephrine transporter (NET) availability has not been explored yet. We investigated ten obese individuals (body mass index (BMI) 42.4 ± 3.7 kg/m 2 ) and ten normal-weight healthy controls (HC, BMI 23.9 ± 2.5 kg/m 2 ) with ( S,S )-[ 11 C]-O-methylreboxetine ([ 11 C]MRB) positron emission tomography (PET). All participants completed the TFEQ, which measures cognitive restraint, disinhibition and hunger. Image analysis required magnetic resonance imaging data sets onto which volumes-of-interests were drawn. Tissue time activity curves (TACs) were obtained from the dynamic PET data followed by kinetic modeling of these regional brain TACs applying the multilinear reference tissue model (2 parameters) with the occipital cortex as reference region. Obese individuals scored significantly higher on the hunger subscale of the TFEQ. Correlative data analysis showed that a higher degree of hunger correlated negatively with the NET availability of the insular cortex in both obese individuals and HC; however, this finding was more pronounced in obesity. Further, for obese individuals, a negative correlation between disinhibition and NET BP ND of the locus coeruleus was detected. In conclusion, these initial data provide in vivo imaging support for the involvement of the central NE system in maladaptive eating behaviors such as susceptibility to hunger.

Objective The structure of neurocognition is explored by examining the neurocognitive domains underlying comprehensive neuropsychological assessment of cognitively healthy individuals. Method Exploratory factor analysis was conducted on the adult normative dataset of an expanded Halstead-Reitan Battery (eHRB), comprising Caucasian and African American participants. The factor structure contributions of the original HRB, eHRB expansion, and Wechsler intelligence scales were compared. Demographic effects were examined on composite factor scores calculated using confirmatory factor analysis. Results The full eHRB had an eight-factor structure, with latent constructs including: 'working memory', 'fluency', 'verbal episodic memory', 'visuospatial cognition' (visuospatial memory and problem solving), 'perceptual-motor speed' (speed for processing visual/tactile material and hand-motor execution), 'perceptual attention' (attention to sensory-perceptual information), 'semantic knowledge' (knowledge acquired through education and culturally-based experiences), and 'phonological decoding' (grapheme-phoneme processing essential for sounding-out words). 'Perceptual-motor speed' and 'perceptual attention' were most negatively associated with age, whereas 'semantic knowledge' and 'phonological decoding' were most resistant to aging. 'Semantic knowledge' showed the greatest dependence on demographic background, including education and ethnicity. Gender differences in cognitive performances were negligible across all domains except 'phonological decoding' with women slightly outperforming men. The original HRB contributed four neurocognitive domains, the eHRB expansion three domains, and the Wechsler scales one additional domain but with restructuring of verbal factors. Conclusion Eight neurocognitive domains underlie performance of healthy cognitive individuals during comprehensive neuropsychological assessment. These domains serve as framework for understanding the constructs measured by commonly-used neuropsychological tests and may represent the structure of neurocognition.

Tamarixia radiata (Waterson) (Hymenoptera: Eulophidae) is a specialist parasitoid of late-instar nymphs of Asian citrus psyllid, Diaphorina citri (Kuwayama) (Hemiptera: Liviidae), a vector of the causal agent of huanglongbing disease of citrus (Sapindales: Rutaceae). Tamarixia radiata is mass reared; however, parasitism levels following inundative releases have remained relatively low. One possible explanation for the low parasitism levels is the lack of sugar resources available for adult wasps in targeted release landscapes, such as abandoned commercial citrus groves and residential areas. Establishing nectar plants can be an effective means of increasing nutritional resources in targeted sites for biocontrol agents. Some eulophids forage effectively only on fully exposed nectaries, i.e., those unobstructed by other floral parts. Therefore, care must be taken to select plants that possess nectary architecture compatible with parasitoid morphology and foraging ability. A series of laboratory studies were undertaken as a first step to determine the potential for T. radiata to obtain sugar from natural sources in target landscapes. Following contact with a sugar spot on filter paper, the wasps engaged in stereotypical zigzagging movements, demonstrating that contact with sugar induced arrestment and induction of localized searching behavior. Tamarixia radiata fed on sugars found in nectar (sucrose, glucose, fructose) and honeydew (melizitose, raffinose), indicating that it should feed well on both nectar and honeydew resources. At the highest concentration tested (1 M), it preferred sucrose and melizitose, whereas at the lowest concentration tested (0.1 M), it preferred sucrose and glucose. There was no preference among sugars when tested at the 0.5 M concentration. Choice tests with wasps previously exposed to scented sucrose solution showed that the wasps were stimulated and attracted by nectar odor and could learn to associate a particular odor with the presence of nectar. Observations conducted with starved wasps on freshly cut sprigs of nectar plants showed that foraging success was highest on extrafloral nectaries and flowers with exposed nectaries. The wasps readily located the extrafloral nectaries on snap bean and cowpea, and fed on them for the majority of the observation periods. Likewise, they quickly located the fully exposed nectaries in the inflorescences of euphorbiaceous plants, such as Euphorbia heterophylla L. (Malpighiales: Euphorbiaceae). Foraging success declined in flowers with nectaries that were only partially exposed; the wasps' movements were deterred by floral parts or trichomes that obstructed the nectary. The wasps were unable to obtain nectar from composites and other plants with hidden nectaries. Overall, the results of these laboratory evaluations showed that T. radiata responds to sugars and chemical cues associated with nectaries and is capable of foraging on extrafloral nectaries and flowers with exposed nectaries.

Asian citrus psyllid, Diaphorina citri, transmits Candidatus Liberibacter asiaticus (CLas), the putative causal agent of Huanglongbing disease. Although they primarily feed on the phloem of Citrus and related plants, when grove or host conditions are unfavorable, D. citri may be able to use weed species as alternate food sources for survival. To explore this possibility, electrical penetration graph (EPG) recordings (18 h) were performed to investigate the feeding behavior of psyllid adults and nymphs on three common south Florida weeds (Bidens alba, Eupatorium capillifolium, and Ludwigia octovalvis). EPG recordings revealed that the proportion of time spent by D. citri feeding on xylem was similar on all tested weed species (19%&ndash, 22%) and on the positive control (20%), the preferred host, Citrus macrophylla. Very little to no phloem feeding was observed on weed species by either nymphs or adults. Histological studies using epifluorescence microscopy showed that salivary sheaths were branched and extended into xylem of weed species, whereas they ended in phloem on citrus plants. No choice behavioral assays showed that adults can obtain some nutrition by feeding on weed species (xylem feeding) and they may be able to survive on them for short intervals, when host conditions are unfavorable.

An ‘attract-and-kill’ (AK) device was evaluated for suppression of adult Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), on residential citrus. The AK device, made from weather-resistant plasticized PVC, lured D. citri adults by simulating the color of citrus flush and killed them with beta-cyfluthrin. This study evaluated: 1) lethality of AK devices weathered up to 8 wk on residential citrus; 2) survival of psyllids caged with potted plants and AK devices; 3) psyllid suppression achieved by AK devices on individual dooryard trees. AK devices weathered for up to 8 wk remained lethal to psyllids. Greenhouse trials evaluated survival of adult psyllids caged for 4 d with orange jasmine plants that were: 1) treated with an (beta-cyfluthrin-infused) AK device; 2) treated with a blank (no insecticide) AK device; or 3) ‘untreated’ with no AK device. After 4 d, psyllid survival was on average 95% lower among adults exposed to plants with AK devices than adults exposed to untreated plants or plants with blank AK devices. Less than half of the adults exposed to plants with AK devices were alive after 1 d and nearly all were dead after 4 d. Deployment of 20 AK devices per tree provided significant psyllid suppression on infested lemon trees from winter to summer and reduced mean reproduction (cumulative eggs) by 91% and mean attack intensity (cumulative psyllid-days) of adults by 59% and nymphs by 53%. AK devices could be an effective control option for D. citri in urban areas.