Jay R. Johnson

Services for offenders with mental impairments: A Texas model

SummaryThe Texas Council on Offenders with Mental Impairments stands as a model for envisioning and implementing the resolutions to problems of service development and delivery to offenders with mental impairments. Acting upon an uncommon sensitivity to the range of problems experienced by persons incarcerated with mental impairments, consumer groups, elected officials, and agency administrators moved to create the Council. The Councils coalition membership cuts across disciplines and agencies to promote close, effective coordination and collaboration. Most importantly, the Council was conceived, organized, mobilized, and continues to operate with advocacy as its primary guiding principle.The Texas Council on Offenders with Mental Impairments is an exemplary experiment in promoting the development and delivery of services for offenders with mental impairments specifically, and special populations generally. It has (1) battled stigma through dissemination of accurate and timely research information; (2) advocated for innovative interventions for its target populations; (3) engaged the leadership and commitment of government officials around its legislative initiatives; and (4) fostered a continuum of services through coordinating the activities of separate agencies and different disciplines. It deserves the continued attention of those interested in studying, and those concerned with ameliorating, the problems of special populations, the development and administration of service organizations, and the operation of state government.Under difficult circumstances and within a context of a clear reticence among some state officials to support public mental health initiatives, any such initiatives undertaken must be aimed toward success at their inception. The factors that effected the Councils initial efforts toward success can be summarized briefly as: (1) comprehensive mandates and the latitude to intervene; (2) a broad-based interagency constituency; (3) legislative backing; and, above all, (4) the authority to generate and distribute funds (Steadman, McCarty, & Mossissey, 1989).

Offenders with mental impairments: What is to be done?

ConclusionHeretofore, the ostensibly disjointed and polarized nature of the two systems conveys the impression that uniting them to address the plight of OMIs in insurmountable, overwhelming, and improbable. Failure to bridge the two systems continues to exacerbate the uncoordinated use of resources and increases the costs of intervention without appreciable effect (Diamond & Schnee, 1991). In other words, unifying the two systems is required to avoid the non-therapeutic and non-rehabilitative practice of punishing OMIs who blunder into crime rather than treating them for the disorders that suffer them to blunder. At the least, this communication will hopefully improve the plight of OMIs by stimulating dialogues through which others can offer their own experiences.

Ultrasonic Transmission Behavior in Posidonia oceanica Rhizomes

The roots and rhizomes of seagrass can form a complicated multi-phase layer within sediments. Gas channels in the rhizomes, known as aerenchyma, give rise to a complicated acoustic response. A model for acoustic propagation through such rhizomes would be beneficial for acoustic remote sensing communities. Ex situ measurements of the ultrasonic sound speed through the dense woody structure of the rhizomes of the seagrass Posidonia oceanica are presented. Ultrasonic (1–5 MHz) time-of-flight measurements were made with the rhizomes segments aligned both lengthwise and crosswise to the propagation direction of the acoustic pulse. The acoustic behaviors of plants collected from different locations in the Mediterranean are compared to each other and to the behaviors of the associated leaf blade tissues. Two measurements were also made of rhizomes before and after degassing the aerenchyma, to quantify the effects of entrained gasses on acoustic behavior. [Work supported by ONR and ONR Global.]

High-frequency acoustic scattering from aquatic plants and seagrass leaf blades

Aquatic plants and seagrasses play a vital role in the littoral zone and shallow water ecosystems. They are important for carbon sequestration, habitat health, and seabed stabilization. Both aquatic plants and seagrasses are vascular plants with gas-filled internal channels, known as aerenchyma, with complex acoustic responses. Many previous field and laboratory experiments have shown that the acoustic response of vascular aquatic vegetation depends on tissue gas content, leaf blade structure, plant density, and photosynthetic activity, yet forward predictive models for acoustic propagation in aquatic plants and seagrass have not been realized. To help progress towards such a model, laboratory bistatic acoustic scattering measurements at 1 MHz were performed on aquarium raised Vallisneria spiralis. The measured results are compared to forward scattering measurements, at the same frequency, performed on naturally collected Mediterranean seagrasses Posidonia oceanica and Cymodocea nodosa. Microscopic images...

Low frequency acoustic properties of Posidonia oceanica seagrass leaf blades

The acoustics of seagrass meadows impacts naval and oceanographic sonar applications. To study this environment, a one-dimensional resonator was used to assess the low-frequency (1-5 kHz) acoustic response of the leaf blades of the Mediterranean seagrass Posidonia oceanica in water. Three separate collections of plants from Crete, Greece, and Sicily, Italy were investigated. A high consistency in effective sound speed was observed within each collection while a strong variability was observed between different collections. Average size, mass, and epiphytic coverage within each collection were quantified, and discoloration and stiffness are discussed qualitatively with respect to the observed acoustic variability.

Variations in ultrasonic transmission behavior along seagrass leaf blades

Seagrass is a complex multi-phase material, and an effective method for connecting acoustic propagation through seagrass meadows to internal or external characteristics of the seagrass would be beneficial for acoustic remote sensing applications. To investigate some of these connections, ultrasonic (1, 2.25, and 5 MHz) time-of-flight measurements through individual leaf blades of the endemic Mediterranean seagrasses Posidonia oceanica and Cymodocea nodosa are presented. Acoustic measurements were made at multiple points along the leaf blades and the sound speed and signal attenuation varied significantly within a single blade depending on measurement location. The measured acoustic variations are compared to external blade features such as discoloration, epiphyte coverage, and thickness. Microscopy images of blade cross-sections each taken at each acoustic measurement location are used to compare the void fraction to acoustic behavior. [Work supported by ONR, ONR Global.]Seagrass is a complex multi-phase material, and an effective method for connecting acoustic propagation through seagrass meadows to internal or external characteristics of the seagrass would be beneficial for acoustic remote sensing applications. To investigate some of these connections, ultrasonic (1, 2.25, and 5 MHz) time-of-flight measurements through individual leaf blades of the endemic Mediterranean seagrasses Posidonia oceanica and Cymodocea nodosa are presented. Acoustic measurements were made at multiple points along the leaf blades and the sound speed and signal attenuation varied significantly within a single blade depending on measurement location. The measured acoustic variations are compared to external blade features such as discoloration, epiphyte coverage, and thickness. Microscopy images of blade cross-sections each taken at each acoustic measurement location are used to compare the void fraction to acoustic behavior. [Work supported by ONR, ONR Global.]

Low-frequency acoustic behavior of photosynthetically active seagrasses

Acoustic remote sensing techniques are an important tool for mapping seagrass coverage. Three different photosynthesis-related processes can occur in seagrasses that affect the acoustic behavior. First, the air channels within the leaf pressurize with produced gas. Next, bubbles form on the leaf blades. Finally, some of these bubbles break off and enter the water column. A one-dimensional acoustic resonator technique was adapted to monitor the photosynthetic activity of two Mediterranean seagrasses, Posidonia oceanica and Cymodocea nodosa. Measurements of the low-frequency (1–8 kHz) effective sound speed of a mixture of seagrass leaf blades and artificial seawater were taken at regular intervals during periods of no direct light and exposure to photosynthetically active radiation. The acoustic response is compared to independent dissolved oxygen measurements and visual observation of bubble formation.

Measurement of low-frequency tissue response of the seagrass Posidonia oceanica

A one-dimensional acoustic resonator technique was used to study leaves of the Mediterranean seagrass species Posidonia oceanica collected from Crete and Sicily. The leaf blades were finely divided, mixed with artificial seawater, and degassed to create a suspension of tissue independent of leaf structure and free bubbles or internal voids. The low-frequency (1 to 8 kHz) bulk modulus of the leaf tissue was inferred from the acoustic measurements and independent density measurements. The measured density of the seagrass tissue was 960 ± 20 kg/m3 which agrees with previously published values. The inferred bulk modulus was 2.1 GPa with 90% confidence limits 1.0-5.0 GPa.

Ultrasonic characterization of seagrass leaf blades (Posidonia oceanica)

It has been shown that simple mixture theory models are inadequate to describe low-frequency sound propagation through seagrass meadows and further understanding of the acoustic properties of seagrass tissue is necessary. To that end, we present two ultrasonic sound speed measurements on the Mediterranean seagrass Posidonia oceanica. First, a transit time measurement through a stack of 120 leaf blades at 2.25 MHz are compared to similar measurements made on macroalgae Ecklonia radiata. Sound speed differences are related to the gas content within the aerenchyma of seagrass and other tissue characteristics. Second, ultrasonic sound speed measurements through a suspension of finely divided P. oceanica leaf blades at frequencies between 1 and 4 MHz are compared to low-frequency (1-8 kHz) sound speed obtained on the same blade suspension by means of a resonance chamber.

Additional studies of the acoustics of coffee roasting

Cracking sounds emitted by coffee beans during the roasting process can be recorded by a microphone and used as the basis for automated acoustic roast profiling and monitoring, mimicking what expert artisanal coffee roasters do by ear. Three parameters are used for this purpose. Near the end of the roasting process, sounds known as “first crack” exhibit a higher acoustic amplitude than sounds emitted later, known as “second crack.” First crack emits more low frequency energy than second crack. Finally, the rate of cracks appearing in the second crack chorus is higher than the rate in the first crack chorus. This presentation is a companion to the previously published work on the same topic [J. Acoust. Soc. 185, EL265–EL269 (2014)], but expanded to include a discussion of automated crack detection signal processing, the acoustic characteristics of different coffee beans, and initial results of a study on how individual beans crack and emit their sounds.