Photon Antibunching in the Photoluminescence Spectra of a Single Carbon Nanotube

We report the first observation of photon antibunching in the photoluminescence from single carbon nanotubes. The emergence of a fast luminescence decay component under strong optical excitation indicates that Auger processes are partially responsible for inhibiting two-photon generation. Additionally, the presence of exciton localization at low temperatures ensures that nanotubes emit photons predominantly one by one. The fact that multiphoton emission probability can be smaller than 5% suggests that carbon nanotubes could be used as a source of single photons for applications in quantum cryptography.Comment: content as publishe

Relations of meaning in life and sense of coherence to distress in cancer patients: a meta-analysis

OBJECTIVE: Cancer patients report high rates of distress. The related constructs of meaning in life (MiL) and sense of coherence (SOC) have long been recognized as important factors in the psychological adjustment to cancer; however, both constructs' associations with distress have not been quantitatively reviewed or compared in this population. Informed by Park's integrated meaning-making model and Antonovsky's salutogenic model, the goals of this meta-analysis were the following: (1) to compare the strength of MiL-distress and SOC-distress associations in cancer patients; and (2) to examine potential moderators of both associations (i.e., age, gender, ethnicity, religious affiliation, disease stage, and time since diagnosis). METHODS: A literature search was conducted using electronic databases. Overall, 62 records met inclusion criteria. The average MiL-distress and SOC-distress associations were quantified as Pearson's r correlation coefficients and compared using a one-way ANOVA. RESULTS: Both MiL and SOC demonstrated significant, negative associations with distress (r = -0.41, 95% CI: -0.47 to -0.35, k = 44; and r = -0.59, 95% CI: -0.67 to -0.51, k = 18, respectively). Moreover, the MiL-distress association was significantly smaller than the SOC-distress association (Qb  = 10.42, df = 1, p < 0.01). Neither association varied by the tested moderators. CONCLUSIONS: Findings provide support for the clinical relevance of MiL and SOC across demographic and medical subgroups of cancer patients. The strength of the SOC-distress association suggests that incorporating aspects of SOC (e.g., the perceived manageability of life circumstances) into meaning-centered interventions may improve their effectiveness for distressed cancer patients

A meta-analysis of the relationship between social constraints and distress in cancer patients

Social constraints on cancer-related disclosure have been associated with increased distress among cancer patients. The goals of this meta-analysis were: (1) to quantify the average strength of the relationships between social constraints and general and cancer-specific distress in cancer patients; and (2) to examine potential moderators of these relationships. A literature search was conducted using electronic databases, and 30 studies met inclusion criteria. Moderate, significant relationships were found between social constraints and both general distress (r = 0.37, 95 % CI 0.31-0.43) and cancer-specific distress (r = 0.37, 95 % CI 0.31-0.44). The relationship between social constraints and cancer-specific distress was stronger for studies of patients who, on average, had been diagnosed more recently. Relationships between social constraints and both general and cancer-specific distress did not vary by age or gender. Findings suggest that social constraints may be important to target in interventions to reduce distress in cancer patients, especially those who have been recently diagnosed

Research Notes: A spontaneous mutant at the st2 locus

In 1971, Detroy Green, Department of Agronomy, Iowa State University, found sterile plants in an F4 single-plant progeny row from a cross of Hark X Harosoy Dt2Dt2. This family segregated 66 fertile to 21 sterile plants. Microspore mother cells of the sterile plants were examined, and a low level of chromosome pairing was observed, indicating that the sterile was either an asynaptic or desynaptic mutant

Associations of health behaviors with human papillomavirus vaccine uptake, completion, and intentions among female undergraduate students

This study explored associations between health behaviors and human papillomavirus vaccine receipt/intentions among female undergraduates. Participants (N = 286) completed a survey assessing human papillomavirus vaccine uptake (receiving 1–3 shots vs no shots), completion (receiving 3 shots vs 1–2 shots), and intentions as well as various health behaviors. Human papillomavirus vaccine uptake and completion were associated with receipt of other preventive medical care; completion was associated with having a regular healthcare provider. Among unvaccinated students (n = 115), increased human papillomavirus vaccine intentions were associated with flu shot and human immunodeficiency virus test receipt. Findings suggest promoting human papillomavirus vaccination with other preventive medical care might improve vaccine receipt

Self-efficacy mediates the relationship between social norms and HPV vaccine intentions in undergraduate students

poster abstractHuman papillomavirus (HPV) is the most common sexually transmitted infection in the United States. The HPV vaccine reduces incidences of genital warts and certain cancers among both men and women. Unfortunately, many undergraduate students have not been vaccinated. Previous research suggests students are more likely to report greater intentions to get vaccinated when others (e.g., friends, physicians) believe they should receive the vaccine; that is, greater social norms are associated with greater vaccine intentions. However, few studies have examined potential mediators of this association. Drawing from the Theory of Planned Behavior and the Health Belief Model, we hypothesized that social norms would be related to vaccine intentions through self-efficacy. Undergraduate students (N=210) who had not received the HPV vaccine completed an online survey. Participants were predominately White (72%), female (67%), heterosexual (92%), and on average 19.9 years of age (SD=3.2). Forty-nine percent were in a romantic relationship, and 55% were sexually active within the past three months. Participants completed HPV vaccine specific measures, including social norms regarding vaccination, self-efficacy for vaccination, and vaccine intentions. Two mediation analyses (one per gender) were conducted to examine whether self-efficacy mediated the relationship between social norms and vaccine intentions. For women and men, greater social norms were related to greater self-efficacy, and greater selfefficacy was related to greater vaccine intentions (ps<0.05); additionally, social norms were indirectly related to vaccine intentions through self-efficacy (p<0.05). For women, after accounting for self-efficacy, social norms were still significantly related to intentions (p<0.05). For men, however, after accounting for self-efficacy, social norms were not significantly related to intentions (p=0.75). Consistent with previous findings, social norms were positively related to vaccine intentions; however, we found that this association was mediated by self-efficacy. Future intervention studies should consider targeting social norms and improving students’ confidence in their ability to obtain the vaccine

Relationships between Health Behaviors and HPV Vaccine Receipt and Intentions among Undergraduate Women

poster abstractThe human papillomavirus (HPV) vaccine represents an important step in reducing cervical cancer incidence and mortality. In recent years, this vaccine has been routinely recommended for females under the age of 26; however, only one-third of adolescent females have initiated the 3-shot HPV vaccine series. Although a number of studies have identified predictors of HPV vaccination, few have examined its correlations with other health behaviors. Evidence suggests that health-enhancing behaviors (e.g., healthy diet, physical activity) tend to cluster together. In this study, we examined the relationships between health behaviors and HPV vaccine receipt and intentions among undergraduate women at IUPUI. Participants (N=286) completed an internet-based survey that included measures of health behaviors (e.g., diet and exercise, vaccination history, recent physical examination) as well as questions regarding HPV vaccine receipt and intentions (i.e., likelihood of being vaccinated). Participants were, on average, 19 years old (SD=1.9). The majority were Caucasian (75%), single (90%), sexually active (65%), and recipients of the HPV vaccine (58%). Results showed significant relationships between HPV vaccine receipt and the receipt of other medical care, including a flu shot in the past year (χ2(1, N=260)=3.88, p<.05), a Pap smear in the past three years (χ2(1, N=263)=6.49, p<.05), and a recent dental visit (r=.15, p<.05). Among those who had not received the HPV vaccine, increased HPV vaccine intentions were associated with the receipt of the flu shot in the past year (r=.19, p<.05) and the receipt of HIV testing (r=.19, p<.05). However, HPV vaccine receipt and intentions were not significantly related to engagement in any of the other health behaviors (e.g., diet and exercise). Findings suggest that HPV vaccine uptake and intentions to receive the vaccine are associated with the receipt of other preventative medical care among female undergraduates

Cancer-related loneliness mediates the relationships between social constraints and symptoms among cancer patients

Cancer patients have high rates of persistent and disabling symptoms. Evidence suggests that social constraints (e.g., avoidance and criticism) negatively impact symptoms, but pathways linking these variables have yet to be identified. This study examined whether cancer-related loneliness (i.e., feeling socially disconnected related to having cancer) mediated the relationships between social constraints and symptoms (i.e., pain interference, fatigue, sleep disturbance, and cognitive complaints) in patients with various cancers (N = 182). Patients (51% female, mean age = 59) were recruited from the Indiana Cancer Registry and completed questionnaires assessing social constraints, cancer-related loneliness, and symptoms. Structural equation modeling was used to evaluate the hypothesized relationships among variables. The model demonstrated good fit. Consistent with our hypothesis, cancer-related loneliness mediated the relationships between social constraints and each symptom. Findings suggest that addressing cancer-related loneliness in symptom management interventions may mitigate the negative impact of social constraints on outcomes

A systematic review of psychosocial interventions for colorectal cancer patients

PURPOSE: A significant minority of colorectal cancer (CRC) patients experience clinically meaningful distress that may warrant intervention. The goal of this systematic review was to assess the impact of psychosocial interventions on quality-of-life and psychosocial outcomes for CRC patients. METHODS: A systematic search of CINAHL, MEDLINE, PsycINFO, and PsycARTICLES was undertaken to obtain relevant randomized controlled trials (RCTs) published through October 2016. RESULTS: Fourteen RCTs of psychosocial interventions for CRC patients were identified. Only three of these RCTs showed significant intervention effects on multiple mental health outcomes. These interventions included written and verbal emotional expression, progressive muscle relaxation training, and a self-efficacy enhancing intervention. Eight of the 14 trials, testing a range of psychoeducational and supportive care interventions, produced little to no effects on study outcomes. An evaluation of RCT quality highlighted the need for greater rigor in study methods and reporting. CONCLUSION: A limited evidence base supports the efficacy of psychosocial interventions for CRC patients. Large-scale trials are needed before drawing definitive conclusions regarding intervention impact

Research Notes: Iowa State University, Ames, and United States Department of Agriculture

The male-sterile (female-fertile) mutant ms1 is identified by three characteristic features. Kenworthy et al. (1973) reported occurrence of twin seedlings, at a low frequency. We are reporting the two additional characteristics: failure of cytokinesis following telophase II; and production of twice as many pollen mother cells as are found in male-fertile sibs