Data are summarized from 152 single-subject analyses of the reinforcing functions of self-injurious behavior (SIB). Individuals with developmental disabilities referred for assessment and/or treatment over an 11-year period were exposed to a series of conditions in which the effects of antecedent and consequent events on SIB were examined systematically by way ofmultielement, reversal, or combined designs. Shook, Keith Slifer, and G. Linden Thorn for the special panel concluded that, although much is known about SIB at the present time, thorough understanding and eventual reduction in the frequency of SIB will require continued research on all aspects of the disorder, induding prevalence, etiology, treatment, and prevention.In an attempt to define the general parameters of SIB as a clinical disorder, a number of investigators have conducted group surveys using methods roles they played in developing or maintaining the clinical environments that accommodated this research. Michael Dorsey is now at the South Bay

No abstract

Because there are potentially serious limitations to differential reinforcement of other behavior (DRO) (which is probably the most widely used treatment procedure for behavior problems), we examined an alternative procedure--noncontingent reinforcement (NCR). Three females with developmental disabilities, all of whom engaged in severe self-injurious behavior, participated. During a pretreatment functional analysis, each subject's self-injury was shown to be differentially sensitive to social attention as a maintaining consequence. Next, each subject was exposed to a DRO treatment and an NCR treatment. During DRO, attention was delivered contingent on the absence of self-injury for prespecified intervals. During NCR, attention was delivered on a fixed-time schedule that was not influenced by the subject's behavior. Results showed that both procedures were highly effective in reducing self-injury, probably because the functional reinforcer for self-injury was used during treatment. Furthermore, there was evidence that NCR attenuated several of the limitations of DRO. These results are particularly interesting in light of the long experimental history of NCR as a control rather than as a therapeutic procedure.

No abstract

Venoarterial extracorporeal membrane oxygenation (VA-ECMO)—also referred to as extracorporeal life support—is a form of temporary mechanical circulatory support and simultaneous extracorporeal gas exchange. The initiation of VA-ECMO has emerged as a salvage intervention in patients with cardiogenic shock, even cardiac arrest refractory to standard therapies. Analogous to veno-venous ECMO for acute respiratory failure, VA-ECMO provides circulatory support and allows time for other treatments to promote recovery or may be a bridge to a more durable mechanical solution in the setting of acute or acute on chronic cardiopulmonary failure. In this review, we provide a brief overview of VA-ECMO, the attendant physiological considerations of peripheral VA-ECMO, and its complications, namely that of left ventricular distention, bleeding, heightened systemic inflammatory response syndrome, thrombosis and thromboembolism, and extremity ischemia or necrosis.

Implantation of the total artificial heart improved the rate of survival to cardiac transplantation and survival after transplantation. This device prevents death in critically ill patients who have irreversible biventricular failure and are candidates for cardiac transplantation.

Despite decades of research progress, ecologists are still debating which pools and fluxes provide nitrogen (N) to plants and soil microbes across different ecosystems. Depolymerization of soil organic N is recognized as the rate-limiting step in the production of bioavailable N, and it is generally assumed that detrital N is the main source. However, in many mineral soils, detrital polymers constitute a minor fraction of total soil organic N. The majority of organic N is associated with clay-sized particles where physicochemical interactions may limit the accessibility of N-containing compounds. Although mineralassociated organic matter (MAOM) has historically been considered a critical, but relatively passive, reservoir of soil N, a growing body of research now points to the dynamic nature of mineral-organic associations and their potential for destabilization. Here we synthesize evidence from biogeoscience and soil ecology to demonstrate how MAOM is an important, yet overlooked, mediator of bioavailable N, especially in the rhizosphere. We highlight several biochemical strategies that enable plants and microbes /doi.org/10.1007/s10533-018-0459-5 to disrupt mineral-organic interactions and access MAOM. In particular, root-deposited low-molecularweight exudates may enhance the mobilization and solubilization of MAOM, increasing its bioavailability. However, the competitive balance between the possible fates of N monomers-bound to mineral surfaces versus dissolved and available for assimilation-will depend on the specific interaction between mineral properties, soil solution, mineral-bound organic matter, and microbes. Building off our emerging understanding of MAOM as a source of bioavailable N, we propose a revision of the Schimel and Bennett (Ecology 85:591-602, 2004) model (which emphasizes N depolymerization), by incorporating MAOM as a potential proximal mediator of bioavailable N.123 Biogeochemistry (2018) 139:103-122 https:/

No abstract