SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: San Diego

104

The El Niño-Southern Oscillation is the dominant mode of interannual climate variability across the Pacific Ocean basin, with influence on the global climate. The two end members of the cycle, El Niño and La Niña, force anomalous oceanographic conditions and coastal response along the Pacific margin, exposing many heavily populated regions to increased coastal flooding and erosion hazards. However, a quantitative record of coastal impacts is spatially limited and temporally restricted to only the most recent events. Here we report on the oceanographic forcing and coastal response of the 2015-2016 El Niño, one of the strongest of the last 145 years. We show that winter wave energy equalled or exceeded measured historical maxima across the US West Coast, corresponding to anomalously large beach erosion across the region. Shorelines in many areas retreated beyond previously measured landward extremes, particularly along the sediment-starved California coast.

Concepts: United States, Weather, California, Alaska, Ocean, Marine debris, San Diego, San Francisco

29

Exosphaeromaamplicauda (Stimpson, 1857) from the west coast of North America is reviewed and redescribed and revealed to be a group of closely related species. A neotype is designated and the species redescribed based on the neotype and topotypic specimens. Exosphaeromaamplicauda is known only from the coast of California, at Marin, Sonoma and San Mateo Counties. Exosphaeromaaphrodita (Boone, 1923), type locality La Jolla, California and previously considered nomen dubium is taken out of synonymy and re-validated. A further three species: Exosphaeromapaydenae sp. n., Exosphaeromarussellhansoni sp. n., and Exosphaeromapentcheffi sp. n. are described herein. Sphaeromaoctonctum Richardson, 1899 is placed into junior synonymy with Exosphaeromaamplicauda. A key to the Pacific West Coast Exosphaeroma is provided.

Concepts: United States, California, North America, Los Angeles, San Diego, Zoological nomenclature, San Francisco, Nomen dubium

1

Melanoma incidence is increasing among Hispanics/Latinos in California. This community-based project reached out to a rural Hispanic/Latino community in North San Diego County to provide melanoma prevention and screening education. At a local community health fair, bilingual volunteer lay health workers led 10- to 15-minute-long information sessions on melanoma disease, risk factors, and skin self-examination techniques. Pearson chi-square analyses of participants' (N = 34) responses to pre- and postintervention evaluation surveys indicate significant increases in knowledge, risk awareness, and self-efficacy for self-screening. The results revealed that Hispanics/Latinos in a low socioeconomic stratum might be at moderate to high risk for developing melanoma. Their low annual income, low level of education, occupational sun-exposure, and lack of access to health care are likely factors that deter at-risk Hispanics/Latinos from seeking health care.

Concepts: Health care, Health care provider, Medicine, Healthcare, Public health, Epidemiology, Educational psychology, San Diego

0

This study compared the accuracy of the FreeStyle Libre (Abbott, Alameda, CA) and Dexcom G4 Platinum (DG4P, Dexcom, San Diego, CA) CGM sensors.

Concepts: California, San Diego, Diego

0

Smoking methamphetamine is associated with increased risk of HIV among female sex workers (FSW). The structural context of substance use is an important shaper of individual behaviour; however, structural determinants of methamphetamine use among FSWs are largely unknown. We identified individual, structural and neighbourhood factors associated with smoking methamphetamine among FSWs in the border city of Tijuana, Baja California, Mexico.

Concepts: California, Mexico, San Diego, Baja California peninsula, Gulf of California, Baja California, Mexicali, Tijuana

0

The West Coast of the United States experienced variable and sometimes highly unusual oceanographic conditions between 2012 and 2015. In particular, a warm mass of surface water known as the Pacific Warm Anomaly (popularly as “The Blob”) impinged on southern California in 2014, and warm-water conditions remained during the 2015 El Niño. We examine how this oceanographic variability affected delivery and individual characteristics of larval spotted sand bass (Paralabrax maculatofasciatus) to an estuarine nursery habitat in southern California. To quantify P. maculatofasciatus settlement patterns, three larval collectors were installed near the mouth of Mission Bay, San Diego CA, and retrieved weekly from June-October of 2012-2015. During ‘Blob’ conditions in 2014 and 2015, lower settlement rates of spotted sand bass were associated with higher sea surface temperature and lower wind speed, chlorophyll a (chl a) and upwelling. Overall, the number of settlers per day peaked at intermediate chl a values across weeks. Individual characteristics of larvae that settled in 2014-2015 were consistent with a poor feeding environment. Although settlers were longer in length in 2014-15, fish in these years had slower larval otolith growth, a longer larval duration, and a trend towards lower condition, traits that are often associated with lower survival and recruitment. This study suggests that future settlement and recruitment of P. maculatofasciatus and other fishes with similar life histories may be adversely affected in southern California if ocean temperatures continue to rise in the face of climate change.

Concepts: Fish, Temperature, California, Pacific Ocean, San Diego, Southern Border, Sea surface temperature, West Coast of the United States

0

From 12 May 2013 to 29 May 2013, the Gull-billed Tern (Gelochelidon nilotica) colony at the San Diego Bay National Wildlife Refuge, California, experienced a mass die-off of at least 92 adults, representing 71-92% of the breeding population on the US west coast. Cause of death was determined to be peritonitis due to perforations of the intestine by a large quantity of acanthocephala (Profilicolis [=Polymorphus] altmani). This is a unique report of P. altmani infecting G. nilotica, and a report of a great impact to a tern population in southern California. Mole crabs (Emerita analoga), the intermediate host for P. altmani and a major component of the Gull-billed Tern diet in San Diego, were found in the stomachs of necropsied terns along with cystacanths, and are the presumed source of the parasite infection. The tern’s dietary reliance upon mole crabs likely amplified parasite transmission and infection. We suggest additional research to determine factors that influence parasite infection of intermediate and definitive hosts, particularly mole crabs, given that they are a vital resource for migrating birds within the coastal zone.

Concepts: Bird, California, San Diego, Bird migration, West Coast of the United States, Tern, Gull-billed Tern, Sternidae

0

Black tar heroin is typically prepared for injection with heat which decreases the risk of HIV transmission by inactivating the virus. We received reports that persons who inject drugs (PWID) in Tijuana, Baja California, Mexico, a black tar heroin market, were using only water to dissolve heroin.

Concepts: Petroleum, California, Mexico, San Diego, Baja California peninsula, Gulf of California, Baja California, Mexicali

0

Schools can address critical sexual and reproductive health (SRH) issues among youth. However, little is known about SRH education being implemented in charter schools. Thus, our purpose was to explore implementation of SRH education in charter schools.

Concepts: Sexual intercourse, Learning, Sexuality, San Diego, Southern Border, Orange County, California

0

Molluscan shell debris is an under-exploited means of detecting, sourcing, and age-dating dredged sediments in open-shelf settings. Backscatter features on the Southern California shelf are suggestive of dredged sediment hauled from San Diego Bay but deposited significantly inshore of the EPA-designated ocean disposal site. We find that 36% of all identifiable bivalve shells >2mm (44% of shells >4mm) in sediment samples from this ‘short dump’ area are from species known to live exclusively in the Bay; such shells are absent at reference sites of comparable water depth, indicating that their presence in the short-dump area signals non-compliant disposal rather than natural offshore transport or sea level rise. These sediments lack the shells of species that invaded California bays in the 1970s, suggesting that disposal preceded federal regulations. This inexpensive, low-tech method, with its protocol for rejecting alternative hypotheses, will be easy to adapt in other settings.

Concepts: California, Shell, Ocean, Mollusca, San Diego, San Diego County, California, Shell, Wyoming, San Francisco Bay Area