Posttraumatic stress moderates return intentions: a factorial survey experiment with internally displaced persons in Nigeria

Background: Persons displaced by conflict often consider returning to their area of origin. Lack of reliable information about conditions in the area of origin makes this decision more difficult. Displaced persons address this by seeking information from other sources, but must then assess the credibility of these sources.Objective: This study examines the role of symptoms of posttraumatic stress as a moderator of how information from a trustworthy source influences return intentions among displaced persons.Method: We test our hypotheses with a factorial survey experiment, drawing participants (N = 822) from residents of internally displaced person (IDP) camps in northeastern Nigeria.Results: Information from a more trustworthy source led to increased return intentions. However, the more participants reported symptoms of posttraumatic stress, the smaller the effect source trustworthiness had on their return intentions.Conclusions: Findings highlight how traumatic experiences during wartime can undermine the effectiveness of the provision of information from a trustworthy source about good conditions in displaced persons' areas of origin, and suggest that interventions addressing posttraumatic stress could have downstream effects on safe, durable, and dignified return.

Socio-ecologic Correlates of HIV/AIDS-Related Sexual Risk Behavior of African American Emerging Adults

There is growing evidence showing that patterns of individual sexual risk behaviors are insufficient in explaining the disproportionate HIV/AIDS burden borne by African Americans. Instead, dynamic features of social, economic, political, and geographic contexts play a more determining role. However, not enough studies have examined the impact of multi-level factors including neighborhood-level influences on HIV/AIDS sexual risk among African American emerging adults using a socio-ecologic perspective. Anchored on the socio-ecologic framework, this study examines the collective role of relevant socio-ecologic determinants of sexual risk-taking among African American emerging adults. Results from both bivariate and multivariate analyses revealed that individual and neighborhood-level variables were significantly associated with sexual risk in our study population partially confirming the hypothesis of the study. Male gender, educational attainment, and neighborhood social disorder were the strongest predictors of sexual risk. Our findings contribute to the vast literature on sexual risk behavior patterns of young adults, and increasing evidence demonstrating the role of contextual factors as stronger predictors of sexual risk and HIV infection among at-risk youth. Our findings, however, underscore the need for further research on the pathways of HIV socio-behavioral vulnerability in this demographic group.

20-Hz pulses and other vocalizations of fin whales, Balaenoptera physalus, in the Gulf of California, Mexico

Low-frequency vocalizations were recorded from fin whales, Balaenoptera physalus, in the Gulf of California, Mexico, during three cruises. In March 1985, recorded 20-Hz pulses were in sequences of regular 9-s interpulse intervals. In August 1987, nearly all were in sequences of doublets with alternating 5- and 18-s interpulse intervals. No 20-Hz pulse sequences of any kind were detected in February 1987. The typical pulse modulated from 42 to 20 Hz and its median duration was 0.7 s (1985 data). Most other fin whale sounds were also short tonal pulses averaging 82, 56, and 68 Hz, respectively, for the three cruises; 89% were modulated in frequency, mostly downward. Compared to Atlantic and Pacific Ocean regions, Gulf of California 20-Hz pulses were unique in terms of frequency modulation, interpulse sound levels, and temporal patterns. Fin whales in the Gulf may represent a regional stock revealed by their sound characteristics, a phenomenon previously shown for humpback whales, birds, and fish. Regional differences in fin whale sounds were found in comparisons of Atlantic and Pacific locations.

Sounds, source levels, and associated behavior of humpback whales, southeast Alaska

Humpback whales in Southeast Alaskan waters produced five categories of sounds: moans, grunts, pulse trains, blowhole-associated sounds, and surface impacts. Frequencies (Hz) of moans and grunts were 20-1900. Major energy in low-frequency pulse trains was in a band of 25-80 Hz with pulse duration of 300-400 ms. Blowhole-associated sounds, recorded as transiting whales encountered one another, were of two types: shrieks, 555-2000 Hz, and trumpetlike horn blasts with fundamental at 414 Hz (median). Pulses and spread spectrum noise were associated with gas bubble formation and explosive bursts, respectively, in connection with spiral feeding maneuvers. Surface impacts resulted from fluke or flipper slaps in sequences of 3-21 sounds. Source levels ranged from 162 (low-frequency pulse trains) to 192 dB (surface impacts), re: 1 microPa, 1 m. Songs, commonly heard on winter breeding grounds, were absent from our recordings. Feeding and perhaps certain other whale activities can be monitored based on sound production.