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From February 2019 through January 2021, data were collected by an acoustic vector sensor moored on the seafloor at a depth of approximately 900 m just outside of Monterey Bay, California, near a major shipping lane off the California coast. Analysis of the vector sensor data has shown the ability to accurately determine bearings to merchant vessels at ranges up to 60 km. This paper examines the features of the low-frequency soundscape using spectral probability densities and evaluates directional features through vector intensity processing as well as coherent linear and adaptive processing of the vector sensor channels. Merchant vessel acoustic data were analyzed using the 1/3 octave band centered at 63 Hz. Over the period analyzed, a reduction in merchant vessel noise was observed between February and June 2020 relative to the same period in 2019, consistent with a reduction in vessel traffic due to the worldwide response to COVID-19. The directional features of the data evaluated through adaptive processing methods also suggest this reduction can be most clearly distinguished towards the south, where the shipping lane is limited to transiting vessels, rather to the north-northwest, where merchant vessels tend to congregate on approach into the San Francisco Bay area. [ABSTRACT FROM AUTHOR]

Malcohn J. Rogers (1930) described artifacts in his field notes that he referred to as stone saws. Recent excavations at CA-SNI-25 yielded numerous utilized sandstone artifacts that might very well be the saws noted by Rogers. In this paper, we describe the production, use, and function of these tools and their spatial distribution across the site. Experiments show that these tools were capable of working a variety of materials, including wood, sea mammal bone, and marine shell; however, our study suggests that they were probably used for the manufacture of circular shell fishhooks. [ABSTRACT FROM AUTHOR]

The article discusses a study on the fall-prevention protocol of the Scripps Mercy Hospital Definitive Observation Unit (DOU) in California. It states that fall rates in hospitals continue to exceed the benchmark of the California Nursing Outcomes Coalition (CalNOC) despite a nationally recognized fall prevention protocol. The protocol in the study was evaluated through an evidenced-based practice (BP) framework. Results revealed that staff champions and resources are essential elements for changing practices that are vital to fall reduction.

Epidemiologic studies have shown that airborne particulate matter (PM) with a mass median aerodynamic diameter < 10 µm (PM[sub 10]) is associated with an increase in respiratory-related disease. However, there is a growing consensus that particles < 2.5 µm (PM[sub 2.5]), including many in the ultrafine (< 0.1 µm) size range, may elicit greater adverse effects. PM is a complex mixture of organic and inorganic compounds; however, those components or properties responsible for biologic effects on the respiratory system have yet to be determined. During the fall and winter of 2000-2001, healthy adult Sprague-Dawley rats were exposed in six separate experiments to filtered air or combined fine (PM[sub 2.5]) and ultrafine portions of ambient PM in Fresno, California, enhanced approximately 20-fold above outdoor levels. The intent of these studies was to determine if concentrated fine/ultrafine fractions of PM are cytotoxic and/or proinflammatory in the lungs of healthy adult rats. Exposures were for 4 hr/day for 3 consecutive days. The mean mass concentration of particles ranged from 190 to 847 µg/m³. PM was enriched primarily with ammonium nitrate, organic and elemental carbon, and metals. Viability of cells recovered by bronchoalveolar lavage (BAL) from rats exposed to concentrated PM was significantly decreased during 4 of 6 weeks, compared with rats exposed to filtered air (p < 0.05). Total numbers of BAL cells were increased during 1 week, and neutrophil numbers were increased during 2 weeks. These observations strongly suggest exposure to enhanced concentrations of ambient fine/ultrafine particles in Fresno is associated with mild, but significant, cellular effects in the lungs of healthy adult rats. [ABSTRACT FROM AUTHOR]

Several letters to the editor are presented in response to articles in previous issues including "New Zealand lessons may aid efforts to control light brown apple moth in California," by Lucia Varela in the January-March 2010 issue, "Native Bees Enrich Urban Gardens," in the July-September 2009 issue, and "Native bees are a rich natural resource in urban California gardens," in the July-September 2009 issue.