Environmental strigolactone drives early growth responses to neighboring plants and soil volume in pea.

There has been a dramatic recent increase in the understanding of the mechanisms by which plants detect their neighbors,1 including by touch,2 reflected light,3 volatile organic chemicals, and root exudates.4,5 The importance of root exudates remains ill-defined because of confounding experimental variables6,7 and difficulties disentangling neighbor detection in shoot and roots.8-10 There is evidence that root exudates allow distinction between kin and non-kin neighbors,11-13 but identification of specific exudates that function in neighbor detection and/or kin recognition remain elusive.1 Strigolactones (SLs), which are exuded into the soil in significant quantities in flowering plants to promote recruitment of arbuscular mycorrhizal fungi (AMF),14 seem intuitive candidates to act as plant-plant signals, since they also act as hormones in plants,15-17 with dramatic effects on shoot growth18,19 and milder effects on root development.20 Here, using pea, we test whether SLs act as either cues or signals for neighbor detection. We show that peas detect neighbors early in the life cycle through their root systems, resulting in strong changes in shoot biomass and branching, and that this requires SL biosynthesis. We demonstrate that uptake and detection of SLs exuded by neighboring plants are needed for this early neighbor detection, and that plants that cannot exude SLs are outcompeted by neighboring plants and fail to adjust growth to their soil volume. We conclude that plants both exude SLs as signals to modulate neighbor growth and detect environmental SLs as a cue for neighbor presence; collectively, this allows plants to proactively adjust their shoot growth according to neighbor density.

Investigation of SARS-CoV-2 Transmission Associated With a Large Indoor Convention - New York City, November-December 2021.

During November 19-21, 2021, an indoor convention (event) in New York City (NYC), was attended by approximately 53,000 persons from 52 U.S. jurisdictions and 30 foreign countries. In-person registration for the event began on November 18, 2021. The venue was equipped with high efficiency particulate air (HEPA) filtration, and attendees were required to wear a mask indoors and have documented receipt of at least 1 dose of a COVID-19 vaccine.* On December 2, 2021, the Minnesota Department of Health reported the first case of community-acquired COVID-19 in the United States caused by the SARS-CoV-2 B.1.1.529 (Omicron) variant in a person who had attended the event (1). CDC collaborated with state and local health departments to assess event-associated COVID-19 cases and potential exposures among U.S.-based attendees using data from COVID-19 surveillance systems and an anonymous online attendee survey. Among 34,541 attendees with available contact information, surveillance data identified test results for 4,560, including 119 (2.6%) persons from 16 jurisdictions with positive SARS-CoV-2 test results. Most (4,041 [95.2%]), survey respondents reported always wearing a mask while indoors at the event. Compared with test-negative respondents, test-positive respondents were more likely to report attending bars, karaoke, or nightclubs, and eating or drinking indoors near others for at least 15 minutes. Among 4,560 attendees who received testing, evidence of widespread transmission during the event was not identified. Genomic sequencing of 20 specimens identified the SARS-CoV-2 B.1.617.2 (Delta) variant (AY.25 and AY.103 sublineages) in 15 (75%) cases, and the Omicron variant (BA.1 sublineage) in five (25%) cases. These findings reinforce the importance of implementing multiple, simultaneous prevention measures, such as ensuring up-to-date vaccination, mask use, physical distancing, and improved ventilation in limiting SARS-CoV-2 transmission, during large, indoor events.†.

The discrepancy between subjective and objective measures of sleep in older adults receiving CBT for comorbid insomnia.

OBJECTIVE: To examine the effect of cognitive-behavioral therapy for insomnia (CBT-I) on the underreporting of sleep relative to objective measurement, a common occurrence among individuals with insomnia. METHOD: Pre-treatment and post-treatment self-report measures of sleep were compared with those obtained from home-based polysomnography (PSG) in 60 adults (mean age = 69.17; 42 women) with comorbid insomnia. The self-report data were published previously in a randomized controlled trial demonstrating the efficacy of CBT-I compared with a placebo treatment. RESULTS: Self-report measures significantly underestimated sleep at pre-treatment and CBT-I led to a correction in this discrepancy. There were no significant changes in PSG after CBT-I. Path analysis showed that an increase in an objective proxy measure of sleep quality (i.e., decreased stage N1 sleep) after CBT-I was significantly related to improvements in self-report of sleep, with full mediation by reductions in discrepancy. CONCLUSIONS: This is the first CBT-I outcome study to analyze discrepancy changes and demonstrate that these changes account for a significant portion of self-report outcome. In addition, improved sleep quality as measured by a decrease in percentage of stage N1 sleep following treatment may be one mechanism that explains why sleep estimation is more accurate following CBT-I.

Effectiveness of abbreviated CBT for insomnia in psychiatric outpatients: sleep and depression outcomes.

OBJECTIVE: To test the efficacy of cogntive-behavioral therapy for insomnia (CBT-I) as a supplement treatment for psychiatric outpatients. Comorbid insomnia is prevalent among individuals with varied psychiatric disorders and evidence indicates that CBT-I may be effective for reducing insomnia and other psychiatric symptoms. METHOD: The present study randomly assigned 30 psychiatric outpatients (mean duration of treatment = 3.6 years) with low sleep quality and residual depressive symptoms to two sessions of CBT-I or a treatment as usual control group. Assessment included the Pittsburgh Sleep Quality Index (PSQI) for insomnia and the Patient Health Questionnaire (PHQ-9) for depression at pretreatment and 4 and 8 weeks posttreatment. RESULTS: Patients who received CBT-I demonstrated within group changes in PSQI and the PHQ-9 scores at both 4 and 8 weeks posttreatment, but did not show between-group differences. Additionally, 38% of the treatment participants achieved normal sleep at follow-up compared with none in the control condition. CONCLUSIONS: This study provides preliminary evidence that abbreviated behavioral treatment has beneficial effects on residual insomnia and depression in long-term psychiatric outpatients.

Sleep patterns and predictors of disturbed sleep in a large population of college students.

PURPOSE: To characterize sleep patterns and predictors of poor sleep quality in a large population of college students. This study extends the 2006 National Sleep Foundation examination of sleep in early adolescence by examining sleep in older adolescents. METHOD: One thousand one hundred twenty-five students aged 17 to 24 years from an urban Midwestern university completed a cross-sectional online survey about sleep habits that included the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale, the Horne-Ostberg Morningness-Eveningness Scale, the Profile of Mood States, the Subjective Units of Distress Scale, and questions about academic performance, physical health, and psychoactive drug use. RESULTS: Students reported disturbed sleep; over 60% were categorized as poor-quality sleepers by the PSQI, bedtimes and risetimes were delayed during weekends, and students reported frequently taking prescription, over the counter, and recreational psychoactive drugs to alter sleep/wakefulness. Students classified as poor-quality sleepers reported significantly more problems with physical and psychological health than did good-quality sleepers. Students overwhelmingly stated that emotional and academic stress negatively impacted sleep. Multiple regression analyses revealed that tension and stress accounted for 24% of the variance in the PSQI score, whereas exercise, alcohol and caffeine consumption, and consistency of sleep schedule were not significant predictors of sleep quality. CONCLUSIONS: These results demonstrate that insufficient sleep and irregular sleep-wake patterns, which have been extensively documented in younger adolescents, are also present at alarming levels in the college student population. Given the close relationships between sleep quality and physical and mental health, intervention programs for sleep disturbance in this population should be considered.

RESEARCH: Cognitive rehabilitation for bipolar disorder: An open trial for employed patients with residual depressive symptoms.

Bipolar disorder is characterized by recurrent episodes of depression and/or mania along with interepisodic mood symptoms that interfere with psychosocial functioning. Despite periods of symptomatic recovery, individuals with bipolar disorder often continue to experience impairments in psychosocial functioning, particularly occupational functioning. Two determinants of psychosocial functioning of euthymic (neither fully depressed nor manic) individuals with bipolar disorder are residual depressive symptoms and cognitive impairment (i.e., difficulties with executive functioning, attention, and memory). The present study explored whether a new cognitive remediation (CR) treatment designed to treat residual depressive symptoms and, for the first time to the best of our knowledge, address cognitive impairment would be associated with improvement in psychosocial functioning in individuals with bipolar disorder. Following a neuropsychological and clinical assessment 18 individuals with DSM-IV bipolar disorder were treated with 14 individual sessions of CR. Results indicated that at the end of treatment, as well as at the 3-months follow-up, patients showed lower residual depressive symptoms, and increased occupational, as well as overall psychosocial functioning. Pretreatment neuropsychological impairment predicted treatment response. Improvements in executive functioning were associated with improvements in occupational functioning. These findings suggest that treating residual depressive symptoms and cognitive impairment may be an avenue to improving occupational and overall functioning in individuals with bipolar disorder.

Cigarette smoking is associated with suicidality in bipolar disorder.

OBJECTIVES: Cigarette smoking in individuals with bipolar disorder has been associated with suicidal behavior, although the precise relationship between the two remains unclear. METHODS: In this prospective observational study of 116 individuals with bipolar disorder, we examined the association between smoking and suicidality as measured by Linehan's Suicide Behaviors Questionnaire (SBQ) and prospective suicide attempts over a nine-month period. Impulsivity was measured by the Barratt Impulsiveness Scale. RESULTS: Smoking was associated with higher baseline SBQ scores in univariate and adjusted analyses, but was not significant after statistical adjustment for impulsivity in a regression model. A higher proportion of smokers at baseline made a suicide attempt during the follow-up period (5/31, 16.1%) compared to nonsmokers (3/85, 3.5%); p = 0.031, odds ratio = 5.25 (95% confidence interval: 1.2-23.5). Smoking at baseline also significantly predicted higher SBQ score at nine months. CONCLUSIONS: In this study, current cigarette smoking was a predictor of current and nine-month suicidal ideation and behavior in bipolar disorder, and it is likely that impulsivity accounts for some of this relationship.

Cognitive behavioral therapy for rapid-cycling bipolar disorder: a pilot study.

Bipolar disorder is characterized by depressive and/or manic episodes that interfere with daily functioning. Between 10%-24% of bipolar patients experience a rapid-cycling course, with 4 or more mood episodes occurring per year. Characterized by nonresponse to standard mood stabilizing medications, patients with rapid-cycling bipolar disorder are particularly in need of effective, adjunctive treatments. Adjunctive cognitive-behavioral therapy (CBT) has been shown to improve adherence to medication and reduce relapse rates in patients with bipolar disorder. However, no published trials to date have examined the application of CBT to the treatment of patients with a rapid-cycling course of illness, with only a single case study published in the literature. We recently developed a CBT protocol that addresses the specific needs of bipolar patients with rapid cycling. The present study was designed to investigate outcomes with this CBT protocol. Study participants were 10 patients with rapid-cycling bipolar disorder, 6 of whom completed the study. Completers showed significant decreases in depressive mood, and improvements remained stable during the 2-month follow-up. This suggests that CBT for rapid cycling may have beneficial effects.