Farmers lack effective methods to achieve and maintain stable production from year to year in many commercial fruit crops. Annual fruit yield within a region often alternates between high and low ...fruit load and is termed alternate bearing. The underlying cause of alternate bearing is the negative impact of high fruit load on vegetative growth and next year's flowering. In this review, we emphasize common responses of diverse perennials to heavy crop load. We present botanical, ecological and horticultural perspectives on irregular bearing. The later part of this review focuses on understanding how high fruit load dominates over vegetative growth. We discuss sink strengths and putative mobile signals (hormones), perhaps seed-derived. We highlight gaps in current understanding of alternate bearing, and discuss new approaches to better understand fruit load dominance. Assuming the effect of high fruit load may be related to other mechanisms of sink partitioning, other forms of dominance are presented such as apical, first fruit and king fruit dominance. Dominance seems to be enforced, in independent cases through the establishment of a polar auxin transport system from the stronger sink. Once established this somehow perturbs the transport of auxin out of weaker sinks. Possibly, fruit derived auxin may alter the polar auxin transport system of the shoot to inhibit shoot growth.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Dominance inhibition of shoot growth by fruit load is a major factor that regulates shoot architecture and limits yield in agriculture and horticulture crops. In annual plants, the inhibition of ...inflorescence growth by fruit load occurs at a late stage of inflorescence development termed the end of flowering transition. Physiological studies show this transition is mediated by production and export of auxin from developing fruits in close proximity to the inflorescence apex. In the meristem, cessation of inflorescence growth is controlled in part by the age-dependent pathway, which regulates the timing of arrest. Here, we show the end of flowering transition is a two-step process in Arabidopsis (Arabidopsis thaliana). The first stage is characterized by a cessation of inflorescence growth, while immature fruit continues to develop. At this stage, dominance inhibition of inflorescence growth by fruit load is associated with a selective dampening of auxin transport in the apical region of the stem. Subsequently, an increase in auxin response in the vascular tissues of the apical stem where developing fruits are attached marks the second stage for the end of flowering transition. Similar to the vegetative and floral transition, the end of flowering transition is associated with a change in sugar signaling and metabolism in the inflorescence apex. Taken together, our results suggest that during the end of flowering transition, dominance inhibition of inflorescence shoot growth by fruit load is mediated by auxin and sugar signaling.
Psychotic symptoms occur more frequently in the general population than psychotic disorder and index risk for psychopathology. Multiple studies have reported on the prevalence of these symptoms using ...self-report questionnaires or clinical interviews but there is a lack of consensus about the prevalence of psychotic symptoms among children and adolescents.
We conducted a systematic review of all published literature on psychotic symptom prevalence in two age groups, children aged 9-12 years and adolescents aged 13-18 years, searching through electronic databases PubMed, Ovid Medline, PsycINFO and EMBASE up to June 2011, and extracted prevalence rates.
We identified 19 population studies that reported on psychotic symptom prevalence among children and adolescents. The median prevalence of psychotic symptoms was 17% among children aged 9-12 years and 7.5% among adolescents aged 13-18 years.
Psychotic symptoms are relatively common in young people, especially in childhood. Prevalence is higher in younger (9-12 years) compared to older (13-18 years) children.
Achievement emotions are critical because of their impact on success and failure in important domains such as learning. These emotions may be modified via emotion regulation (ER). The dominant ...process model of ER (PMER) proposed by J. Gross, however, provides a domain-general account of ER strategies and has not had substantial contact with theories of achievement emotions such as R. Pekrun's control-value theory (CVT) and the academic achievement literature. Moreover, ER has not been a focal point of major theories related to achievement emotions, such as CVT. We propose an integrated model of ER in achievement situations (ERAS) that integrates propositions about the generation of emotions from CVT with propositions about how emotions are regulated and types of ER strategies from PMER. The ERAS model also offers new propositions regarding how different achievement situations, object foci, and time frames, as well as discrete emotions with different appraisal patterns, impact ER strategies.
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BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To investigate the role of internalization of body image ideals as a potential mediator between perceived body acceptance and intuitive eating among college students.
168 undergraduates completed the ...Body Acceptance By Others Scale (BAOS), Sociocultural Attitudes Toward Appearance Questionnaire-3 (SATAQ-3; Internalization-Total and -General, -Athletic subscales), and Intuitive Eating Scale (IES).
Internalization-Total mediated the relationship between BAOS and IES (b=.19, p<.001). Internalization-General was a significant mediator of the BAOS-IES relationship (b=.14, p=.006), while Internalization-Athletic was not (p=.993). Post-hoc analyses stratified by gender followed similar patterns, aside from a negative but nonsignificant relationship between Internalization-Athletic and IES in men (b=-.16, p=.650).
These data suggest that internalization of general (i.e., thin) body image ideals may be more destructive to body satisfaction and adaptive eating styles in college students than athletic-ideal internalization. More research is needed to examine the role of athletic-ideal internalization on body image and eating behaviors.
Epidemiological research has shown that hallucinations and delusions, the classic symptoms of psychosis, are far more prevalent in the population than actual psychotic disorder. These symptoms are ...especially prevalent in childhood and adolescence. Longitudinal research has demonstrated that psychotic symptoms in adolescence increase the risk of psychotic disorder in adulthood. There has been a lack of research, however, on the immediate clinicopathological significance of psychotic symptoms in adolescence.
To investigate the relationship between psychotic symptoms and non-psychotic psychopathology in community samples of adolescents in terms of prevalence, co-occurring disorders, comorbid (multiple) psychopathology and variation across early v. middle adolescence.
Data from four population studies were used: two early adolescence studies (ages 11-13 years) and two mid-adolescence studies (ages 13-16 years). Studies 1 and 2 involved school-based surveys of 2243 children aged 11-16 years for psychotic symptoms and for emotional and behavioural symptoms of psychopathology. Studies 3 and 4 involved in-depth diagnostic interview assessments of psychotic symptoms and lifetime psychiatric disorders in community samples of 423 children aged 11-15 years.
Younger adolescents had a higher prevalence (21-23%) of psychotic symptoms than older adolescents (7%). In both age groups the majority of adolescents who reported psychotic symptoms had at least one diagnosable non-psychotic psychiatric disorder, although associations with psychopathology increased with age: nearly 80% of the mid-adolescence sample who reported psychotic symptoms had at least one diagnosis, compared with 57% of the early adolescence sample. Adolescents who reported psychotic symptoms were at particularly high risk of having multiple co-occurring diagnoses.
Psychotic symptoms are important risk markers for a wide range of non-psychotic psychopathological disorders, in particular for severe psychopathology characterised by multiple co-occurring diagnoses. These symptoms should be carefully assessed in all patients.
To navigate in the world, an animal’s brain must produce commands to move, change direction, and negotiate obstacles. In the insect brain, the central complex integrates multiple forms of sensory ...information and guides locomotion during behaviors such as foraging, climbing over barriers, and navigating to memorized locations. These roles suggest that the central complex influences motor commands, directing the appropriate movement within the current context. Such commands are ultimately carried out by the limbs and must therefore interact with pattern generators and reflex circuits that coordinate them. Recent studies have described how neurons of the central complex encode sensory information: neurons subdivide the space around the animal, encoding the direction or orientation of stimuli used in navigation. Does a similar central-complex code directing movement exist, and if so, how does it effect changes in the control of limbs? Recording from central-complex neurons in freely walking cockroaches (Blaberus discoidalis), we identified classes of movement-predictive cells selective for slow or fast forward walking, left or right turns, or combinations of forward and turning speeds. Stimulation through recording wires produced consistent trajectories of forward walking or turning in these animals, and those that elicited turns also altered an inter-joint reflex to a pattern resembling spontaneous turning. When an animal transitioned to climbing over an obstacle, the encoding of movement in this new context changed for a subset of cells. These results indicate that encoding of movement in the central complex participates in motor control by a distributed, flexible code targeting limb reflex circuits.
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•Central-complex cells in the freely walking cockroach encode forward and turning speed•Stimulation through recording wires produces movement in a consistent trajectory•Stimulation alters a limb reflex consistent with changes during spontaneous turns•Population activity changes when movement is combined with climbing over a barrier
Martin et al. describe how movement direction is encoded in the central complex of a freely walking insect. Cells subdivide the range of movements (forward and turning speed). The activity of these cells results in changes in limb reflexes that redirect movement. The code is context dependent: activity is altered when animals must climb a barrier.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Individuals who report psychotic-like experiences are at increased risk of future clinical psychotic disorder. They constitute a unique "high-risk" group for studying the developmental trajectory to ...schizophrenia and related illnesses. Previous research has used screening instruments to identify this high-risk group, but the validity of these instruments has not yet been established. We administered a screening questionnaire with 7 items designed to assess psychotic-like experiences to 334 adolescents aged 11-13 years. Detailed clinical interviews were subsequently carried out with a sample of these adolescents. We calculated sensitivity and specificity and positive predictive value (PPV) and negative predictive value (NPV) for each screening question for the specific symptom it enquired about and also in relation to any psychotic-like experience. The predictive power varied substantially between items, with the question on auditory hallucinations ("Have you ever heard voices or sounds that no one else can hear?") providing the best predictive power. For interview-verified auditory hallucinations specifically, this question had a PPV of 71.4% and an NPV of 90.4%. When assessed for its predictive power for any psychotic-like experience (including, but not limited to, auditory hallucinations), it provided a PPV of 100% and an NPV of 88.4%. Two further questions-relating to visual hallucinations and paranoid thoughts-also demonstrated good predictive power for psychotic-like experiences. Our results suggest that it may be possible to screen the general adolescent population for psychotic-like experiences with a high degree of accuracy using a short self-report questionnaire.
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► Function of key floral transition regulators appears to be conserved in plants. ► FT transcript accumulation or TFL1 transcript depletion correlates with floral induction in several ...fruit trees. ► Fruit load may inhibit floral induction by reducing FT transcript accumulation. ► A memory of high fruit load could be stored until flower induction.
In many commercial fruit crop species, high fruit load inhibits vegetative growth and floral induction. As a result, trees that had a high fruit load will bear few flowers and fruit the following year, along with abundant vegetative growth. We previously discussed how high fruit load interferes with concurrent shoot growth. Here we focus on how high fruit load impacts the process of flowering. Ascertaining the precise time at which specific buds begin the floral transition in each species is challenging. The use of indirect approaches to determine time of floral induction or evocation may lead to questionable conclusions. Annual and perennial plants appear to use conserved proteins for flowering induction and initiation. The accumulation or reduction of transcripts encoding proteins similar to Arabidopsis (annual) FLOWERING LOCUS T (FT) and TERMINAL FLOWER1 (TFL1), respectively, correlates well with flower induction in several diverse species. The recent use of such markers provides a means to formulate an accurate timeframe for floral induction in different species and holds promise in providing new insight into this important developmental event. A role for hormones in modulating the inhibitory effect of fruit load on floral induction is also discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
•Adverse childhood experiences (ACEs) are linked to poorer cognition in early adulthood.•Both deprivation- and threat-type and higher cumulative ACEs predicted cognition.•Screening and tailored ...treatments addressing ACEs and cognition may be warranted.
Adverse childhood experiences (ACEs) may have lasting impacts on cognition.
To determine if ACE exposure is prospectively associated with cognition in young adults. We hypothesized that deprivation- and threat-type ACEs as well as higher cumulative ACE exposure predict poorer cognition.
Participants were from the National Longitudinal Study of Adolescent to Adult Health (Add Health), a prospective cohort investigation of U.S. adolescents followed to adulthood. Current study participants were 18−24 years old (Wave III), 24−32 years old (Wave IV), and 31–42 years old (Wave V). The maximum Wave IV sample was 12,288 adults; Wave V was 1277 adults.
History of ACEs were assessed at Wave III. Three cognitive indicators were assessed at Wave IV and Wave V using the Rey Auditory Verbal Learning Test (immediate and delayed verbal memory) and the Digit-Span Backward Task (working memory).
The deprivation ACE of not-having-basic-needs met was associated with poorer working (β = 0.14, CI95 -0.26, −0.01), immediate (β=−0.29, CI95 −0.43, −0.15), and delayed memory (β=-0.27, CI95 −0.43, −0.12) at Wave IV; poorer immediate (β=−0.47, CI95–0.79, −0.16) and delayed memory (β=−0.33, CI95 -0.65, −0.01) at Wave V. The threat ACE of sexual abuse was associated with poorer immediate (β=−0.40, CI95 −0.62, −0.17) and delayed memory (β=−0.29, CI95 −0.55, −0.03) at Wave IV. Higher cumulative ACEs predicted poorer delayed memory (β =−0.05, CI95 −0.10, −0.01) at Wave V.
Higher ACEs, especially deprivation-type, were prospectively linked to poorer cognition. Early wide-scale screening/tailored treatments addressing ACEs and cognitive function may be warranted.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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