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In recent years, zero-tolerance policies have been implemented in an attempt to reduce violent and/or drug-related activities in schools. These policies are sometimes expanded to include less serious crimes, which raises a number of questions regarding juvenile justice (JJ) system response and processing. This article discusses the need, implementation, and some preliminary program outcomes related to a civil citation (CC) process undertaken to provide an alternative to school-based justice referrals. Aggregate trends were reviewed based on internal program data as well as publicly available information. Follow-up data on CC youth were obtained and a matched sample of youth not engaged in the CC process was created using a state-level administrative data set to provide a preliminary assessment of outcomes. Key informant interviews examined program development and implementation. Results of this preliminary evaluation are considered in the larger context of youth diversion and school-based practices for dealing with youth misconduct.

Designed for use on unloaded exchange cable, this repeater was developed to satisfy the transmission requirements of an experimental PCM system. It utilizes a pulse repetition frequency of 1.544 mc, and 6000‐ft repeater spacing. Functionally, the repeatered line transmits the PCM signal without appreciable degradation over distances up to 25 miles, a feat accomplished by retiming and reshaping the signal at each repeater point. Retiming is accomplished by means of a clock extracted from the signal; reshaping is accomplished by regeneration with positive pulse width control. Near‐end crosstalk and pulse train jitter dominate the design parameters. Timing is made tolerant of near‐end crosstalk by choice of bipolar transmission (where successive marks are of opposite polarity) with clock derived from the rectified and clipped signal. Tolerance in the decision circuit is obtained by automatic threshold control, spike sampling, and tight control of time and voltage parameters. Accumulated pulse train jitter is controlled to the extent dictated by the terminal equipment, principally through control of the bandwidth of the clock circuit. Seven diffused‐base transistors and ten logic diodes are used in the one‐way repeater circuit. A two‐way repeater consists of two such circuits with a common power unit, utilizes 135 components, and is packaged in a can of 11/16 × 31/8 × 53/4‐inches outside dimensions. Accommodations are made for line‐length and power options, as well as remote testing. Power for the repeater is transmitted over the signal pair. One watt is required for the two‐way repeater.

Background: Extracellular vesicles (EVs) secreted from adipose-derived mesenchymal stem cells (ADSCs) (ADSC-EVs) improve flap survival after ischemia–reperfusion injury. Exposure of parent ADSCs to oxidative stress has been shown to enhance this effect, but mechanisms are unclear. We aimed to determine whether angiogenesis-promoting protein and microRNA (miRNA) content is altered in EVs after preconditioning with hydrogen peroxide (H2O2 ADSC-EVs) and whether H2O2 ADSC-EVs can increase viability of random pattern skin flaps. Methods: EVs secreted by human ADSCs were isolated after culture in EV-depleted medium ± H2O2. Nanoparticle tracking analysis determined size and concentration of purified EVs. Mass spectrometry and small RNA next-generation sequencing were performed to compare proteomic and miRNA profiles. ADSC-EVs, H2O2 ADSC-EVs, or vehicle were injected into random pattern skin flaps of BALB/c mice (4–5 mice per group). Viable and necrotic areas were measured on day 7, and tissues underwent histologic analysis. Results: Angiogenic and antimicrobial protein content of EVs was altered with H2O2 preconditioning. Functional enrichment analysis identified constitutive photomorphogenesis 9 signalosome (known to direct vascular endothelial growth factor production) as the major enriched Gene Ontology term unique to H2O2 ADSC-EVs. Two miRNAs were increased, and 12 (including 10 antiangiogenic miRNAs) were reduced in H2O2 ADSC-EVs. Enhanced viability (P < 0.05) of flaps treated with H2O2 ADSC-EVs compared with vehicle corresponded to increased capillary density in the H2O2 group (P < 0.001). Conclusion: Altered protein and miRNA content in ADSC-EVs after H2O2 pretreatment likely contributes to enhanced therapeutic effects on flap survival observed in preclinical models.